ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Inorganic Chemistry  (3,415)
  • Aerodynamics
  • Fisheries
  • Industrial Chemistry
  • Seismology
  • 2020-2023  (38)
  • 1985-1989  (4,209)
Collection
Keywords
Publisher
Years
Year
  • 1
    facet.materialart.
    Unknown
    Time-dependent stress response seismicity models (TDSR) (2022)
    GFZ Data Services
    Details
    Publication Date: 2022-08-22
    Description: Methods
    Description: The python tool "Time dependent stress response seismicity model (TDSR)" is a modified effective Coulomb failure model to calculate earthquake rates as a function of stress loading and model parameter. The theory and examples are described in Dahm and Hainzl (2022): A Coulomb Stress response model for time-dependent earthquake forecasts, accepted in Journal of Geophysical Research, Solid Earth (doi xxxxxx). The TDSR toolbox is further developed under github at https://github.com/torstendahm/tdsr . A Sphinx generated code documentation and html pages are provided after installation. Examples published in Dahm and Hainzl (2022) are provided as code examples.
    Keywords: Seismology ; Earthquake Rate Forecast ; EARTH SCIENCE 〉 HUMAN DIMENSIONS 〉 NATURAL HAZARDS 〉 EARTHQUAKES ; EARTH SCIENCE SERVICES 〉 ENVIRONMENTAL ADVISORIES 〉 GEOLOGICAL ADVISORIES 〉 EARTHQUAKES ; EARTH SCIENCE SERVICES 〉 MODELS 〉 GEOLOGIC/TECTONIC/PALEOCLIMATE MODELS
    Type: Software , Software
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    DATA GFZ
  • 2
    facet.materialart.
    Unknown
    Yemaya No. 63, May 2021 (2022)
    The International Collective in Support of Fishworkers (ICSF) | India
    Details
    Publication Date: 2022-02-21
    Description: Yemaya No. 63, dated May 2021, features articles from US, The Netherlands, Myanmar, Senegal, and an article on women in fisheries and human rights. The article from the US by Linda Behnken argues that a growing coalition of small-scale, community-based fishers is calling for the recognition and protection of Alaska’s invaluable coastal fisheries during COVID-19. The article from the Netherlands by Cornelie Quist looks at the challenges facing women engaged in small-scale fishing and supplying fish through retailers and how they found new ways to directly reach consumers. The conversation between Miranda Bout and Cornelie Quist focuses on how they combined new product development with the use of social media to contact their customer base during the pandemic-induced disruption of traditional marketing chains. The article by Elena Finkbeiner, Juno Fitzpatrick and Whitney Yadao-Evans looks at recent media revelations and scientific research that have brought increased attention to human-rights violations and the myriad social issues facing fisheries, but with a disproportionate focus on labour-rights violations at sea and in industrial fishing operations. The systemic inequalities combined with the effects of COVID-19 exacerbated vulnerabilities of women to health risks, food and livelihood security. The article from Senegal by Aby Dia from Lumière Synergie pour le Développement (LSD), in collaboration with WoMin African Alliance, South Africa, narrates the story of traditional women fish processors from the Bargny who have been, for more than a decade, struggling against development projects that jeopardise their environment, health and livelihoods. In order to preserve their livelihoods, women processors in Senegal have come together to oppose the Tosyali steel project. The European Network of Women in Fisheries and Aquaculture in Europe (AKTEA) urges the Office of the Commissioner for the Environment, Oceans and Fisheries to integrate gender into all aspects of European fishing policy. The Profile column looks at how Linda Behnken became a fisher in Alaska and how fishing has shaped her individuality and work. Natalie Sattler says that fishing for halibut, sablefish and salmon from the sparkling waters of the Pacific along with her children and at the same time passion for working with the Alaska Longline Fishermen’s Association and the Alaska Sustainable Fisheries Trust is an immense challenge.
    Description: Published
    Description: Refereed
    Keywords: Fishing Communities ; Women in fisheries ; Gender ; Small-scale fisheries ; Aquaculture ; Fisheries
    Repository Name: AquaDocs
    Type: Book/Monograph/Conference Proceedings
    Format: 12p.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 3
    facet.materialart.
    Unknown
    European Fault-Source Model 2020 (EFSM20): online data on fault geometry and activity parameters (2022)
    Details
    Publication Date: 2022-11-18
    Description: Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe (SERA), H2020, grant agreements 730900.
    Description: Published
    Description: 2T. Deformazione crostale attiva
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: 4IT. Banche dati
    Keywords: Geology ; Earth sciences of Europe ; Earth sciences of Africa ; Earth sciences of Asia ; Earth Sciences and Geology ; earthquakes ; hazard model ; seismogenic faults ; slip rate ; crustal fault sources ; subduction fault sources ; Seismology ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: web product
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 4
    facet.materialart.
    Unknown
    Sitios de agregación reproductiva de pargos (Lutjanidae) en el Parque Nacional Cayos de San Felipe, Cuba. (2022)
    Details
    Publication Date: 2022-06-28
    Description: Las pesquerías basadas en las agregaciones reproductivas pueden amenazar a especies como los pargos que tienen conductas gregarias durante el período reproductivo. Esta nota ofrece elementos que sugieren la existencia de sitios de agregación no registrados previamente y no protegidos en el Parque Nacional Cayos de San Felipe (PNCSF), región suroccidental de Cuba. La información tradicional obtenida de pescadores locales y trabajadores del parque se corroboró con muestreos cualitativos y cuantitativos de peces de arrecifes y datos de pesquerías locales del 2014. En la época de reproducción de pargos (mayo a julio) se observaron grupos de entre 40-100 ejemplares de Lutjanus cyanopterus, Lutjanus synagris y Lutjanus jocu en los arrecifes de la zona occidental del PNCSF (camellones entre 15-30 m de profundidad cerca del borde de la plataforma). Dentro de esa área, se señalan dos sitios que parecen ser utilizados para agregaciones de predesove, por lo que requieren protección y ser estudiados. Los censos cuantitativos confirmaron que en mayo y junio la zona occidental tiene densidad alta de pargos adultos. También, el pico de captura de estas especies ocurrió en la época reproductiva. Se comprobó que las pesquerías se realizaron durante las migraciones de peces hacia el borde de la plataforma en áreas de la zona occidental del PNCSF, y que más del 60% de los individuos tuvieron gónadas maduras (antes de desovar). Esta información debe incentivar el estudio de las agregaciones de desove en esta región de Cuba, la protección de especies amenazadas y áreas de alta significación ecológica y la implementación de pesquerías sostenibles.
    Description: Fisheries based on reproductive aggregations can threaten species such as snappers that have gregarious behavior during the reproductive period. This note provides evidence to support the existence of aggregation sites, not previously registered and unprotected, in the National Park San Felipe Keys (NPSFK), southwestern region of Cuba. Traditionalinformation obtained from local fishermen and from the park staff was complemented with qualitative and quantitative fish reef censuses and local fisheries data in 2014. In the reproductive season of snappers (May to July) groups of between 40-100 specimens of Lutjanus cyanopterus, Lutja- nus synagris and Lutjanus jocu were observed in the western area of the NPSFK on the reefs (spoor and grove between 20-30 m deep close to the platform edge). Within that area two sites are indicated that can be used for prespawning aggregation, so they require protection and study. Quanti- tative censuses confirmed that in May and June the western zone has high density of adult snappers. Also, the peak of capture of these snapper species occurred in the reproduc- tive season. It was found that fisheries carried out during fish migrations to the edge of the shelf in areas of the western area of the NPSFK and more than 60% of the individuals had mature gonads (before spawning). This information should promote the study of spawning aggregations in this region of Cuba, the protection of threatened species and areas of high ecological significance and the implementation of sustainable fisheries.
    Description: Published
    Description: Refereed
    Keywords: Región suroccidental de Cuba ; Desove ; Pesquerías ; Migration routes ; Spawning ; Fisheries ; Rutas migraciones
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.54-65
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 5
    facet.materialart.
    Unknown
    Workshop on ICES Reference Points (WKREF2) (2022)
    International Council for the Exploration of the Sea | Copenhagen, Denmark
    Details
    Publication Date: 2022-09-14
    Description: The ICES Workshop on ICES reference points (WKREF2) was tasked review the WKREF1 report and based on the outcome develop updated guidelines for the ICES reference points system and recommendations for ACOM consideration. The WKREF1 report has suggested 5 key recom- mendations to simplify and harmonise the ICES reference points framework representing a ma- jor change to the current guidelines. At WKREF2, we detailed discussions and four key concerns were raised about the proposed approach. The first related to the simplification of rules to define Blim. Around two thirds of category 1 stocks would end up as WKREF1 “Blim Type 2” where Blim would be set as a fraction of B0. The Allee effect or “depensation” maybe more important than previously thought and should be furthered explored for ICES stocks since it has important consequences for Blim. A number of challenges and issues around defining Blim using the current guidelines were documented. Some suggestions on improvement criteria were discussed including using classifiers to define spas- modic stocks and using change point algorithms to address non-stationary productivity regimes. However, further work is need to make these approaches operational and there was no consen- sus that the WKREF1 Blim types should replace the current guidelines. WKREF1 recommended that the FMSY proxy should be based on a biological proxies and should be less than the deterministic FMSY. It was pointed out that the stochastic FMSY estimated in EqSim for example, is lower than the deterministic FMSY and that the current guidelines ensure that the FMSY should not pose a more than 5% risk to Blim. A large amount of work described in WD 1 was carried out to develop an MSE framework to consistency and robustness test a candidate refer- ence point system for North East Atlantic stocks. However, WKREF2 recommended that further work needs to be carried out to condition and test the simulation framework before the conclu- sions could be adopted by ICES and incorporated into the guidelines. A number of considerations for defining MSY related reference points were discussed including using model validation and prediction skill to ensure that ICES provide robust and credible ad- vice. There is evidence that density dependence (DD) is important in the majority of ICES stocks (68% in recruitment and 54% in growth). The correct prediction of the shape and strength of density-dependence in productivity is key to predicting future stock development and providing the best possible long-term fisheries management advice. A suggested approach to use surplus production models (SPMs) to account for DD in FMSY was suggested and discussed but there was no consensus on whether that approach was appropriate. There was consensus that the FECO approach as a means of adapting target fishing mortality to medium-term changes in productiv- ity should be included in the guidelines subject to a benchmark and ACOM approval. While WKREF1 and 2 focused mainly on Category 1 stocks ToR c) called for a “simplified and harmonised set of guidelines for estimating MSY and precautionary reference points applicable in the advice framework across various ICES stock categories.” Ideally the ICES assessment cat- egories should provide equivalent risk across all stocks. This issue was discussed but no recom- mendations emerged. There was no consensus a revised reference point framework was proposed at WKREF2. How- ever, it was agreed that it should be presented here for further discussion at ACOM and other fora. The key feature of the suggested approach is that the stock status evaluation is treated in- dependent of the Advice Rule (AR). The main feature of the system is that the biomass trigger is not linked to a stock status evaluation, it is linked to the expected biomass when fishing at the target fishing mortality, in contrast to the current ICES approach. It also entailed that FMSY would also become an upper limit of fishing mortality and that the advised fishing mortality would be set at or lower than that level. WKREF2 did not discuss what to do in situations where SSB〈 Blim or alternative forms of HCR for the advice rule. Building community understanding and con- sensus around simplified and harmonised guidelines has yet to be achieved. A further workshop WKREF3 will be required to achieve that aim. The report includes 6 recommendations for ACOM consideration.
    Description: ICES
    Description: The main objective of the workshop was to review the recommendations of WKREF1 and con- sider how these might feed into a new reference points framework and guidelines for ICES. There were a number of presentations on the wider issues of best practice for reference points, the Allee effect, density dependence and the WKIRISH approach. The starting point was to try and develop a set of simplified and harmonised guidelines based on the WKREF1 report rather than evolving the current guidelines to include the WKREF1 conclusions. A key aspect of the meeting was to allow for discussions in order to build a shared understanding of the strengths and weakness of the current framework and of the new framework emerging from WKREF1.
    Description: Published
    Description: Non Refereed
    Keywords: ICES ; Reference points ; Management advice ; Fisheries ; Fishery management reference points
    Repository Name: AquaDocs
    Type: Report
    Format: 103pp
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 6
    facet.materialart.
    Unknown
    The economic tradeoffs and ecological impacts associated with a potential mesopelagic fishery in the California Current (2022)
    Ecological Society of America
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Dowd, S., Chapman, M., Koehn, L., & Hoagland, P. The economic tradeoffs and ecological impacts associated with a potential mesopelagic fishery in the California Current. Ecological Applications, 32(4), (2022): e2578, https://doi.org/10.1002/eap.2578.
    Description: The ocean's mesopelagic zone (200–1000 m) remains one of the most understudied parts of the ocean despite knowledge that mesopelagic fishes are highly abundant. Apex predators from the surface waters are known to consume these fishes, constituting an important ecological interaction. Some countries have begun exploring the potential harvest of mesopelagic fishes to supply fishmeal and fish oil markets due to the high fish abundance in the mesopelagic zone compared with overfished surface waters. This study explored the economic and ecological implications of a moratorium on the harvest of mesopelagic fishes such as lanternfish off the US West Coast, one of the few areas where such resources are managed. We adapted a bioeconomic decision model to examine the tradeoffs between the values gained from a hypothetical mesopelagic fishery with the potential values lost from declines in predators of mesopelagic fishes facing a reduced prey resource. The economic rationale for a moratorium on harvesting mesopelagics was sensitive both to ecological relationships and the scale of the nonmarket values attributed to noncommercial predators. Using a California Current-based ecological simulation model, we found that most modeled predators of mesopelagic fishes increased in biomass even under high mesopelagic harvest rates, but the changes (either increases or decreases) were small, with relatively few predators responding with more than a 10% change in their biomass. While the ecological simulations implied that a commercial mesopelagic fishery might not have large biomass impacts for many species in the California Current system, there is still a need to further explore the various roles of the mesopelagic zone in the ocean.
    Description: Sally Dowd acknowledges sponsorship from the WHOI Summer Student Fellowship and the Rausser College of Natural Resources Honors Program at UC Berkeley. This project would not have been possible without the guidance provided by Kama Thieler and Carl Boettiger. Porter Hoagland acknowledges funding from the Audacious Project, a collaborative endeavor, housed at TED and the J. Seward Johnson Fund in support of the Marine Policy Center at WHOI.
    Keywords: Bioeconomic model ; Fisheries ; Mesopelagic fishes ; Moratorium ; Nonmarket value ; Predators ; Rpath ; Willingness-to-pay values
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    The ocean twilight zone’s role in climate change (2022)
    Woods Hole Oceanographic Institution
    Details
    Publication Date: 2022-05-27
    Description: Buesseler, K., Jin, D., Kourantidou, M., Levin, D., Ramakrishna, K., Renaud, P., Ausubel, J., Baltes, K., Gjerde, K., Holland, M., Kostel, K., LaCapra, V., Martin, A., Sosik, H., Thorrold, S., Tierney, T., Joyce, K., Renier, N., Taylor, E. (2022). The Ocean Twilight Zone’s Role in Climate Change. Woods Hole Oceanographic Institution, 32 pp.
    Description: The ocean twilight zone (more formally known as the mesopelagic zone) plays a fundamental role in global climate. It is the mid-ocean region roughly 100 to 1000 meters below the surface, encompassing a half-mile deep belt of water that spans more than two-thirds of our planet. The top of the ocean twilight zone only receives 1% of incident sunlight and the bottom level is void of sunlight. Life in the ocean twilight zone helps to transport billions of metric tons (gigatonnes) of carbon annually from the upper ocean into the deep sea, due in part to processes known as the biological carbon pump. Once carbon moves below roughly 1000 meters depth in the ocean, it can remain out of the atmosphere for centuries to millennia. Without the benefits of the biological carbon pump, the atmospheric CO 2 concentration would increase by approximately 200 ppm 1 which would significantly amplify the negative effects of climate change that the world is currently trying to curtail and reverse. Unfortunately, existing scientific knowledge about this vast zone of the ocean, such as how chemical elements flow through its living systems and the physical environment, is extremely limited, jeopardizing the efforts to improve climate predictions and to inform fisheries management and ocean policy development.
    Description: Funding is: The Audacious Project housed at TED
    Keywords: Climate ; Mesopelagic ; Twilight Zone ; Fisheries ; Carbon Dioxide Removal ; Ocean ; Biological Carbon Pump ; Solubility Pump ; Carbon ; Marine Snow
    Repository Name: Woods Hole Open Access Server
    Type: Other
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    Teleseismic earthquake wavefields observed on the ross ice shelf (2021)
    Cambridge University Press
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baker, M. G., Aster, R. C., Wiens, D. A., Nyblade, A., Bromirski, P. D., Gerstoft, P., & Stephen, R. A. Teleseismic earthquake wavefields observed on the Ross Ice Shelf. Journal of Glaciology, 67(261), (2021): 58-74, https://doi.org/10.1017/jog.2020.83.
    Description: Observations of teleseismic earthquakes using broadband seismometers on the Ross Ice Shelf (RIS) must contend with environmental and structural processes that do not exist for land-sited seismometers. Important considerations are: (1) a broadband, multi-mode ambient wavefield excited by ocean gravity wave interactions with the ice shelf; (2) body wave reverberations produced by seismic impedance contrasts at the ice/water and water/seafloor interfaces and (3) decoupling of the solid Earth horizontal wavefield by the sub-shelf water column. We analyze seasonal and geographic variations in signal-to-noise ratios for teleseismic P-wave (0.5–2.0 s), S-wave (10–15 s) and surface wave (13–25 s) arrivals relative to the RIS noise field. We use ice and water layer reverberations generated by teleseismic P-waves to accurately estimate the sub-station thicknesses of these layers. We present observations consistent with the theoretically predicted transition of the water column from compressible to incompressible mechanics, relevant for vertically incident solid Earth waves with periods longer than 3 s. Finally, we observe symmetric-mode Lamb waves generated by teleseismic S-waves incident on the grounding zones. Despite their complexity, we conclude that teleseismic coda can be utilized for passive imaging of sub-shelf Earth structure, although longer deployments relative to conventional land-sited seismometers will be necessary to acquire adequate data.
    Description: This research was supported by NSF grants PLR-1142518, 1141916, 1142126, 1246151, 1246416 and OPP-1744852 and 1744856.
    Keywords: Glacier geophysics ; Ice shelves ; Seismology
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    Equitable allocations in northern fisheries: bridging the divide for Labrador Inuit (2021)
    Frontiers Media
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kourantidou, M., Hoagland, P., Dale, A., & Bailey, M. Equitable allocations in northern fisheries: bridging the divide for Labrador Inuit. Frontiers in Marine Science, 8, (2021): 590213, https://doi.org/10.3389/fmars.2021.590213.
    Description: Canada has undertaken commitments to recognize the rights of Indigenous Peoples in fisheries through policies and agreements, including Integrated Fishery Management Plans, the Reconciliation Strategy, and Land Claim Agreements (LCAs). In addition to recognizing rights, these commitments were intended to respect geographic adjacency principles, to enhance the economic viability of Indigenous communities, and to be reflective of community dependence on marine resources. We examined the determinants of quota allocations in commercial fisheries involving Nunatsiavut, Northern Labrador, the first self-governing region for the Inuit peoples in Canada. It has been argued that current fishery allocations for Nunatsiavut Inuit have not satisfied federal commitments to recognize Indigenous rights. Indicators that measure equity in commercial allocations for the turbot or Greenland halibut (Reinhardtius hippoglossoides) and northern shrimp (Pandalus borealis) fisheries were identified and assessed. In these two cases, historical allocations continue to predominate for allocations based upon equity or other social or economic considerations. We illustrate equity-enhancing changes in the quota distribution under scenarios of different levels of inequality aversion, and we make qualitative assessments of the effects of these allocations to Nunatsiavut for socioeconomic welfare. This approach could benefit fisheries governance in Northern Labrador, where federal commitments to equity objectives continue to be endorsed but have not yet been integrated fully into quota allocations.
    Description: This research was undertaken with funding from the Canada First Research Excellence Fund through the Ocean Frontier Institute (MK and MB) and the Johnson Endowment of the Woods Hole Oceanographic Institution’s (WHOI) Marine Policy Center (PH).
    Keywords: Fisheries ; Allocations ; Equity ; Indigenous rights ; Access
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Experiments on the induced spawning and larval rearing of the milkfish, Chanos chanos (Forsskal) in 1979 (2021)
    In:  aqdchief@seafdec.org.ph | http://aquaticcommons.org/id/eprint/18569 | 2002 | 2015-11-15 16:06:30 | 18569 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Details
    Publication Date: 2022-08-02
    Description: This paper summarizes the results of the experiments on the induced breeding and larval rearing of milkfish (Chanos chanos) during the 1979 season. Milkfish larvae could be reared successfully without the use of trochophore larvae of oysters as feed during the first few days. In order to induce the ovulation of wild adult milkfish a higher dose of human chorionic gonadotropin hormone is required.
    Keywords: Fisheries ; Chanos chanos ; ISEW ; Philippines ; marine environment ; Brood stocks ; Fish culture ; Fish larvae ; Food organisms ; Induced breeding ; Larval development ; Sex hormones
    Repository Name: AquaDocs
    Type: article
    Format: application/pdf
    Format: application/pdf
    Format: 1-3
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 11
    facet.materialart.
    Unknown
    Knowing Asian aquaculture and fisheries. Part 1 (2021)
    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20100 | 17342 | 2016-02-24 22:18:26 | 20100 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Details
    Publication Date: 2022-08-02
    Description: An outline is given of aquaculture and fisheries in Asia, providing information of use to students whose work can influence laws, rules, policy and regulations on aquaculture and fisheries, with the view in mind to sustainable aquaculture. In this issue, the following countries are examined: China, Indonesia, and Bangladesh.
    Keywords: Aquaculture ; Fisheries ; Fishery management ; Aquaculture development ; Aquaculture regulations ; Marine aquaculture ; Freshwater aquaculture ; Fishery industry ; Asia ; Bangladesh ; China
    Repository Name: AquaDocs
    Type: article
    Format: application/pdf
    Format: application/pdf
    Format: 7-8
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 12
    facet.materialart.
    Unknown
    Knowing Asian aquaculture and fisheries. Part 4 (2021)
    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20067 | 2002 | 2016-03-04 15:16:24 | 20067 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Aquaculture ; Vietnam ; Sri Lanka ; Sri Lanka ; Vietnam ; brackishwater environment ; freshwater environment ; marine environment ; Aquaculture ; Aquaculture techniques ; Brackishwater aquaculture ; Feed ; Fish culture ; Fish diseases ; Fisheries ; Fishery data ; Food organisms ; Freshwater aquaculture ; Marine aquaculture ; Marine fisheries ; Mollusc culture ; Pond culture ; Seaweed culture ; Shrimp culture
    Repository Name: AquaDocs
    Type: article
    Format: application/pdf
    Format: application/pdf
    Format: pp.9-10, 27
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 13
    facet.materialart.
    Unknown
    Knowing Asian aquaculture and fisheries (2021)
    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20055 | 2002 | 2016-03-03 11:33:32 | 20055 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Aquaculture ; Asia ; Cambodia ; India ; Asia ; Cambodia ; India ; Myanmar ; Myanmar ; brackishwater environment ; freshwater environment ; marine environment ; Aquaculture ; Aquaculture development ; Aquaculture economics ; Aquaculture techniques ; Brackishwater aquaculture ; Catching methods ; Culture effects ; Environmental impact ; Fish culture ; Fisheries ; Fishery development ; Fishery resources ; Fishery statistics ; Freshwater aquaculture ; Marine aquaculture ; Shrimp culture ; Sustainability ; Trade
    Repository Name: AquaDocs
    Type: article
    Format: application/pdf
    Format: application/pdf
    Format: pp.9-10, 29
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 14
    facet.materialart.
    Unknown
    Regional survey of heavy metals in fish and fish products: Indonesia (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26291 | 23782 | 2019-04-08 09:42:05 | 26291 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Pollution ; Indonesia ; Heavy metals ; Chemical pollution ; Pollution monitoring
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 10-19
    Format: 10
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 15
    facet.materialart.
    Unknown
    Regional survey of heavy metals in fish and fish products: Myanmar (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26293 | 23782 | 2019-03-22 03:49:21 | 26293 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Myanmar ; Heavy metals ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 38-46
    Format: 9
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 16
    facet.materialart.
    Unknown
    Round scad exploration by purse seine in the South China Sea, Area III: Western Philippines (2021)
    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26259 | 2002 | 2019-03-01 05:56:06 | 26259 | Southeast Asian Fisheries Development Center, Secretariat
    Details
    Publication Date: 2022-08-02
    Description: Round scad exploration by purse seine in the waters of western Philippines was conducted from April 22 to May 7, 1998 for a period of five (5) fishing days with a total catch of 7.3 tons and an average of 1.5 tons per setting. Dominant species caught were Decapterus spp. having 70.09% of the total catch, followed by Selar spp. at 12.66% and Rastrelliger spp. 10.70%. Among the Decapterus spp. caught, D. macrosoma attained the highest total catch composition by species having 68.81% followed by D. kurroides and D.russelli with 0.31% and 1.14% respectively. The round scad fishery stock was composed mainly of juvenile fish (less than 13 cm) and Age group II (13 cm to 14 cm). Few large round scad at Age group IV and V (20 cm to 28 cm) stayed at the fishery. Other fishes caught were: Auxis rochei (0.85%), A. thazard (0.12%), Caranx spp. (0.45%), Emmilichthys nitidus (0.58%), Euthynnus affinis (0.42%), Leiognathus ruconius (0.58%), Loligo sp. (0.31%), Megalaspis cordyla (0.09%), Rastrelliger spp. (10.70%), Sardinella longiceps (0.03%), Scomberoides lysan (0.24%), Selar spp. (12.66%), Sphyraena spp. (0.90%), Thunnus albacares (0.96%) and others (1.02%). Tuna and tuna like fishes such as yellowfin tuna, eastern little tuna, bullet tuna, frigate tuna and oceanic squid are distributed in the upper latitudes of the survey area. On the other hand, round scads, big-eyed scads and Indian mackerels are dominantly present in the lower latitudes of the survey area.
    Keywords: Fisheries ; Exploratory fishing ; Purse seining ; Age composition ; Catch composition ; Fishery surveys ; Carangid fisheries ; South China Sea ; Philippines ; Rastrelliger ; Decapterus
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 49-64
    Format: 16
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 17
    facet.materialart.
    Unknown
    Fisheries in Brunei Darussalam (2021)
    Training Department, Southeast Asian Fisheries Development Center | Samut Prakarn, Thailand
    In:  http://aquaticcommons.org/id/eprint/26215 | 17342 | 2019-02-08 06:25:54 | 26215 | Southeast Asian Fisheries Development Center, Training Department
    Details
    Publication Date: 2022-08-02
    Description: Presented in this paper is the status of the fishery industry in Brunei Darussalam. Specifically, it discussed the following topics: fishery management strategies, zonation scheme, licencing, the use of poisons and explosives, the minimum cod-end mesh size for trawlers, closed areas, enhancement of fishing grounds, and the enforcement activities.
    Keywords: Fisheries ; Fishery resources ; Fishery management ; Fisheries ; Ecological zonation ; Licensing ; Fish poisoning ; Catching methods ; Illegal fishing ; Explosive fishing ; Fishing gear ; Season regulations ; Fishing grounds
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 34-40
    Format: 7
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 18
    facet.materialart.
    Unknown
    Regional survey of heavy metals in fish and fish products: Thailand (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26295 | 23782 | 2019-03-22 08:39:12 | 26295 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Thailand ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 53-58
    Format: 6
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 19
    facet.materialart.
    Unknown
    Regional survey of heavy metals in fish and fish products: Malaysia (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26292 | 23782 | 2019-03-22 03:43:09 | 26292 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Malaysia ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 20-37
    Format: 18
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 20
    facet.materialart.
    Unknown
    Tuna resource exploration with longline in the South China Sea, Area III: Western Philippines (2021)
    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26258 | 2002 | 2019-03-01 06:00:19 | 26258 | Southeast Asian Fisheries Development Center, Secretariat
    Details
    Publication Date: 2022-08-02
    Description: An exploratory tuna longline fishing survey was conducted using the research and training vessels of the Southeast Asian Fisheries Development Center, the 1,178 GT MV SEAFDEC and the Bureau of Fisheries and Aquatic Resources, the 165 GT MV MAYA-MAYA in the South China Sea Waters, West of the Philippines from April to May, 1998. A total of 3,796 hooks was set in sixteen (16) fishing stations. There were no tuna caught during the entire survey but only minor and irrelevant species like the Pacific lancetfish, sharks and an opah species, Lampris guttatus. The important fishing and oceanographic factors during the survey and other research results on longline are described and analyzed. Additional longline studies within and near the Philippines territorial waters are also presented to substantiate the research results of the joint SEAFDEC/BFAR resource exploratory.
    Keywords: Fisheries ; Exploratory fishing ; Catch composition ; Fishery surveys ; Longlining ; Tuna fisheries ; South China Sea ; Philippines
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 39-48
    Format: 10
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 21
    facet.materialart.
    Unknown
    Regional survey of pesticide residues in fish and fish products: Malaysia (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26299 | 23782 | 2019-03-27 06:00:01 | 26299 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Chemistry ; Fisheries ; Malaysia ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Biochemical analysis ; Lethal limits
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 71-74
    Format: 4
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 22
    facet.materialart.
    Unknown
    Regional survey of pesticide residues in fish and fish products: Myanmar (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26300 | 23782 | 2019-03-27 05:58:36 | 26300 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Aquaculture ; Chemistry ; Fisheries ; Myanmar ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Lethal limits
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 75-83
    Format: 9
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 23
    facet.materialart.
    Unknown
    Regional survey of histamine in fish and fish products: Indonesia (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26307 | 23782 | 2019-03-27 03:35:56 | 26307 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Indonesia ; Histamines ; Biological sampling ; Fish ; Fishery products ; Quality control
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 116-123
    Format: 8
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 24
    facet.materialart.
    Unknown
    Regional survey of pesticide residues in fish and fish products: Thailand (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26303 | 23782 | 2019-03-27 05:51:15 | 26303 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Chemistry ; Fisheries ; Thailand ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Dried products ; Lethal limits
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 100-105
    Format: 6
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 25
    facet.materialart.
    Unknown
    Regional survey of histamine in fish and fish products: Myanmar (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26309 | 23782 | 2019-03-27 03:49:31 | 26309 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Keywords: Fisheries ; Myanmar ; Histamines ; Biological sampling ; Biochemical analysis ; Fish ; Fishery products
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 129-133
    Format: 5
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 26
    facet.materialart.
    Unknown
    Determination of chemical properties of meat: Determination of K value (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26826 | 23782 | 2019-11-21 00:56:12 | 26826 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Presented in the paper is the standard procedure in the determination of K value which is an index to measure the enzymatic freshness of fish and squid. Specifically, reagents, apparatus and the analytical procedures needed and the calculations are presented.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fish inspection ; Fishery industry ; Food technology ; Standards ; Specifications
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: B-6.1-B-6.7
    Format: 7
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 27
    facet.materialart.
    Unknown
    Determination of chemical properties of meat: Freshness testing paper (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26825 | 23782 | 2019-11-21 00:52:35 | 26825 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Presented in the paper is the standard procedure in measuring K value in fish meat by means of the freshness testing paper technique.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fish inspection ; Fishery industry ; Food technology ; Standards ; Specifications
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: B-7.1-B-7.2
    Format: 2
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 28
    facet.materialart.
    Unknown
    Determination of physical properties of meat: Measurement of pH (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26802 | 23782 | 2019-11-12 05:28:20 | 26802 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Presented in the paper is the standard procedure in the measurement of pH in the fresh fish meat. Specifically, the procedures in sampling and sample preparation, apparatus and reagents required, and the analytical procedures are presented.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Microbiological analysis ; Fishery products ; Processed fishery products ; Fish inspection ; Fishery industry ; Food additives ; Food technology ; Standards ; Specifications ; pH
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: A-3.1-A-3.2
    Format: 2
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 29
    facet.materialart.
    Unknown
    Analysis of additives: Determination of starch (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26842 | 23782 | 2019-11-15 07:54:48 | 26842 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Starch is commonly used in the production of fish jelly products as an extender and as binding agent. The paper provides the methodology in the determination of starch in fish jelly products. Instructions for sample preparation and the reagents needed are presented. Detailed procedures in the determination of the starch in a sample are provided.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Starch ; Additives ; Food additives
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: D-4.1-D-4.4
    Format: 4
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 30
    facet.materialart.
    Unknown
    Red tides and paralytic shellfish poisoning in the Philippines (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26881 | 23782 | 2019-11-05 02:46:02 | 26881 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Monitoring and investigative work undertaken in the Philippines regarding dinoflagellate blooms are described. Chronological observations of the occurrence of red tides, aerial surveys, spatial distribution of the dinoflagellate and the physical environment are discussed. Fishing and the examination of gut content of fish and mussels and bioassay tests are detailed. Incidents of paralytic shellfish poisoning in the Philippines are considered briefly.
    Keywords: Fisheries ; Health ; Environmental monitoring ; Red tides ; Public health ; Medicine ; Dangerous organisms ; Philippines
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 52-79
    Format: 28
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 31
    facet.materialart.
    Unknown
    Red tide and paralytic shellfish poisoning phenomena in Thailand (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26885 | 23782 | 2019-11-05 02:23:34 | 26885 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: A report is made of the first incidence occurring of paralytic shellfish poisoning in Thailand in May 1983, following an extensive bloom of Trichodesmium erythraeum. Investigations undertaken regarding the source of the toxicity are outlined.
    Keywords: Fisheries ; Health ; Biological poisons ; Public health ; Red tides ; Shellfish ; Dangerous organisms ; Thailand
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 90-91
    Format: 2
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 32
    facet.materialart.
    Unknown
    Red tide and paralytic shellfish poisoning in Sabah, Malaysia (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26879 | 23782 | 2019-11-05 02:54:38 | 26879 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: A brief account is given of recent cases of paralytic shellfish poisoning in Sabah, Malaysia, and toxicological studies undertaken. Hydrography surveys, underwater observations after the occurrence of the red tides and plankton studies and monitoring of red tides are discussed.
    Keywords: Fisheries ; Health ; Shellfish ; Toxicity tests ; Red tides ; Public health ; Dangerous organisms ; Malaysia
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 35-42
    Format: 8
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 33
    facet.materialart.
    Unknown
    Microbiological procedure: Vibrio cholera (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26852 | 23782 | 2019-11-15 07:36:44 | 26852 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Cholera is an acute specific infection caused by the organism, Vibrio cholera. Diagnosis may be confirmed by the presence of large numbers of the comma-shaped bacilli on direct microscopic examination of a fecal or vomitus smear, and by the isolation of the organism on culture. Fish and shellfish have been identified as vehicles of cholera. Large numbers of V. cholera must usually be ingested to cause cholera. Thus problems often occur when poor handling and inadequate refrigeration have allowed the organism to multiply. Presented in the paper is the methodology of determining the presence of Vibrio cholera in fish and fishery products.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Aerobic bacteria ; Microbiological analysis ; Microorganisms ; Pathogenic bacteria ; Pathogens ; Health and safety ; Public health ; Microbial contamination ; Vibrio cholerae
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: E-7.1-E-7.5
    Format: 5
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 34
    facet.materialart.
    Unknown
    Fisheries statistics in Brunei Darussalam (2021)
    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26890 | 23782 | 2019-11-14 01:01:29 | 26890 | Southeast Asian Fisheries Development Center, Secretariat
    Details
    Publication Date: 2022-08-02
    Description: Fishery statistics in Brunei Darussalam have been collected by the Department of Fisheries since the 1940s. In the early 1980s, a number of statistics were collected, such as catch and effort data of artisanal fishermen, aquaculture statistics, processing statistics as well as data from major wet markets focusing on the amount, prices of marketed fish either from the local fishermen or imported. In 1984, the collection of statistics on commercial fishing was started. The statistics have been used in the formulation of fishery management and development policies as well as for sectoral development. Following a brief account of the responsibility and statistic collections of the Department of Fisheries, an examination is made of employment in the fishery sector, fisheries production, fish marketed and the GDP for the fishery industry. Fisheries in Brunei Darussalam is a very healthy industry, where production is well below the maximum allowable harvestable limit of 20,000 tons at 30%. The Department is embarking to increase production from the capture fishery to reduce the country's dependence on imported fish; the same applies for aquaculture, in order to complement production from the capture fisheries. The processing sector is also increasing in importance, especially with the increase in the number of capture fishery licenses, and the demand for quality and value-added products.
    Keywords: Fisheries ; Marine fisheries ; Fishery statistics ; Aquaculture development ; Aquaculture statistics ; Fish catch statistics ; Marine aquaculture ; Freshwater aquaculture ; Fishery development ; Marine ; Brackish ; Freshwater
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 6-14
    Format: 9
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 35
    facet.materialart.
    Unknown
    Analysis of additives: Determination of salt (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26843 | 23782 | 2019-11-15 07:52:55 | 26843 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Sodium chloride is an important additive for the production of fish jelly products. It extracts the salt soluble protein to give the gel strength of the final product. The paper provides the methodology in the determination of the amount of sodium chloride in fish jelly products. Instructions for sample preparation and the reagents needed are presented. Detailed procedures in the determination of the salt in a sample are provided.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Additives ; Food additives ; Salts ; Sodium chloride
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: D-5.1-D-5.2
    Format: 2
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 36
    facet.materialart.
    Unknown
    Microbiological procedure: Vibrio parahaemolyticus (2021)
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26851 | 23782 | 2019-11-14 01:29:31 | 26851 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Details
    Publication Date: 2022-08-02
    Description: Food poisoning due to Vibrio parahaemolyticus is a food-borne infection resulting from the ingestion of a large number of this organism (about 106-109 viable cells). The major symptoms are diarrhea and abdominal pain with headache, fever, and vomiting also occurring. The organisms are excreted during the acute stage of the illness after which they decrease rapidly. The differentiation of V. parahaemolyticus from other pathogenic species of Vibrio is based mainly on salt tolerance, Voges-Proskauer reaction, fermentation of sucrose, and growth at 43°C. Presented in the paper is the methodology of determining the presence of Vibrio cholera in fish and fishery products.
    Keywords: Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Aerobic bacteria ; Microbiological analysis ; Microorganisms ; Pathogenic bacteria ; Pathogens ; Health and safety ; Public health ; Microbial contamination ; Vibrio parahaemolyticus ; Vibrio cholerae
    Repository Name: AquaDocs
    Type: book_section
    Format: application/pdf
    Format: application/pdf
    Format: E-8.1-E-8.6
    Format: 6
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 37
    facet.materialart.
    Unknown
    Inventario de Daños y Efectos Geológicos Co y/o Post-Sísmicos del Sismo Ocurrido el 18 de mayo de 1875, en la Frontera entre Colombia y Venezuela (2020)
    Details
    Publication Date: 2022-04-28
    Description: On the border between Colombia and Venezuela, have occurred seismic events with important records of damage in both countries. In this paper, we study the historical earthquake that took place on May 18, 1875 between 11.15 and 11.30 in the morning (the time was the same for communities in both countries since there was no time zone difference), which is catalogued as a border earthquake due to the report of damages in the cities of both nations. The community of San José de Cúcuta, current capital of the Northern State of Santander, Colombia, registered the greatest number of deaths and damage to buildings. An inventory of the geological damage and co -seismic and postseismic effects was created based on information of previous studies and data obtained from archival primary sources from Colombia and Venezuela. The result is a bi-national database, which includes the summaries of historical descriptions with the effects in the persons and objects, the geological damages and effects observed during the seismic event. These data has led to the creation of a table of MM and EMS-98 intensities, which enables the identification and delimitation of the regions of greater damages. The maximum level intensity is I=10 in the cities of San José de Cúcuta, Villa del Rosario, Pueblo de Cúcuta (San Luis) in Colombia and San Antonio, San Juan de Ureña in Venezuela. Moreover, we formulated a table of intensities using the ESI-2007 INQUA scale, based on the information of geological observations described in historical documents. These data are related to the epicentral zone with an approximate radius of 30 km.
    Description: Published
    Description: 105-263
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: N/A or not JCR
    Keywords: historical seismicity ; destruction of communities ; Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 38
    facet.materialart.
    Unknown
    Seasonal and spatial variations in the ocean-coupled ambient wavefield of the Ross Ice Shelf (2020)
    Cambridge University Press
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baker, M. G., Aster, R. C., Anthony, R. E., Chaput, J., Wiens, D. A., Nyblade, A., Bromirski, P. D., Gerstoft, P., & Stephen, R. A. Seasonal and spatial variations in the ocean-coupled ambient wavefield of the Ross Ice Shelf. Journal of Glaciology, 65(254), (2019): 912-925, doi:10.1017/jog.2019.64.
    Description: The Ross Ice Shelf (RIS) is host to a broadband, multimode seismic wavefield that is excited in response to atmospheric, oceanic and solid Earth source processes. A 34-station broadband seismographic network installed on the RIS from late 2014 through early 2017 produced continuous vibrational observations of Earth's largest ice shelf at both floating and grounded locations. We characterize temporal and spatial variations in broadband ambient wavefield power, with a focus on period bands associated with primary (10–20 s) and secondary (5–10 s) microseism signals, and an oceanic source process near the ice front (0.4–4.0 s). Horizontal component signals on floating stations overwhelmingly reflect oceanic excitations year-round due to near-complete isolation from solid Earth shear waves. The spectrum at all periods is shown to be strongly modulated by the concentration of sea ice near the ice shelf front. Contiguous and extensive sea ice damps ocean wave coupling sufficiently so that wintertime background levels can approach or surpass those of land-sited stations in Antarctica.
    Description: This research was supported by NSF grants PLR-1142518, 1141916, 1142126, 1246151 and 1246416. JC was additionally supported by Yates funds in the Colorado State University Department of Mathematics. PDB also received support from the California Department of Parks and Recreation, Division of Boating and Waterways under contract 11-106-107. We thank Reinhard Flick and Patrick Shore for their support during field work, Tom Bolmer in locating stations and preparing maps, and the US Antarctic Program for logistical support. The seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center at New Mexico Tech. Data collected are available through the IRIS Data Management Center under RIS and DRIS network code XH. The PSD-PDFs presented in this study were processed with the IRIS Noise Tool Kit (Bahavar and others, 2013). The facilities of the IRIS Consortium are supported by the National Science Foundation under Cooperative Agreement EAR-1261681 and the DOE National Nuclear Security Administration. The authors appreciate the support of the University of Wisconsin-Madison Automatic Weather Station Program for the data set, data display and information; funded under NSF grant number ANT-1543305. The Ross Ice Shelf profiles were generated using the Antarctic Mapping Tools (Greene and others, 2017). Regional maps were generated with the Generic Mapping Tools (Wessel and Smith, 1998). Topography and bathymetry data for all maps in this study were sourced from the National Geophysical Data Center ETOPO1 Global Relief Model (doi:10.7289/V5C8276M). We thank two anonymous reviewers for suggestions on the scope and organization of this paper.
    Keywords: Antarctic glaciology ; Ice shelves ; Seismology
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 39
    Electronic Resource
    Electronic Resource
    Novel substituted B2ElVIN2 heterocycles (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 19-24 
    Details
    ISSN: 0009-2940
    Keywords: Bis(diorganoboryl)chalcogenides ; Pyrazaboles ; Pyrazoles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Neuartige Substituierte B2ElVIN2 HeterocyclenDie Bis(diorganoboryl)chalkogenide (R2B)2O [R = C2H5 (3); R2 = 1,5-C8H14 (1)], (R2B)2S [R2 = 1,5-C8H14 (5)], und (R2B)2Se [R2 = 1,5-C8H14 (7)] reagieren mit Pyrazol (Pz) und dessen Derivaten 3-Methylpyrazol (3-MePz) und Indazol (benzo-Pz) in hohen Ausbeuten (65-92%) zu stabilen 1:1-Additionsverbindungen [z. B. 2 (El = O), 4 (El = O), 6 (El = S), 8 (El = Se)]. 1H-, 13C-, 11B-NMR-Spektren und Röntgenstrukturanalysen (von 2 und 6) zeigen eine Grundstruktur mit einem zentralen B2ElN2-Heterocyclus (El = O, S, Se). Die Reaktion von 2 mit R2BH und die Thermolyse von 4 führen zu den dimeren 1-Pyrazolylboranen 9a bzw. 9b.
    Notes: The bis(diorganoboryl) chalcogenides (R2B)2O [R = C2H5 (3); R2 = 1,5-C8H14 (1)], (R2B)2S [R2 = 1,5-C8H14 (5)], and (R2B)2Se [R2 = 1,5-C8H14 (7)] react with pyrazole (Pz) and its derivatives 3-methylpyrazole (3-MePz) and indazole (benzo-Pz) to form in high yields (65-92%) stable 1:1 adducts [e.g. 2 (El = O), 4 (El = O), 6 (El = S) and 8 (El = Se)]. 1H-, 13C-, 11B-NMR spectra and X-ray analyses (of 2 and 6) show a basic structure with a central B2ElN2 (El = O, S, Se) heterocycle. The reaction of 2 with R2BH and the thermolysis of 4 give the dimeric 1-pyrazolylboranes 9a and 9b, respectively.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220104
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 40
    Electronic Resource
    Electronic Resource
    Extrem kurze Quecksilber-Quecksilber-Kontakte in peri-dimercurierten Naphthalinverbindungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 31-36 
    Details
    ISSN: 0009-2940
    Keywords: Mercury - mercury contacts ; Naphthalenediylmercury compounds ; Organomercury compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Extremely Short Mercury-Mercury Contacts in peri-Dimercurated Naphthalene Compounds1-Naphthylmercury chloride (1) and 1,8-naphthalenediylbis(mercury chloride) (2) were prepared from the corresponding naphthyllithium precursors and HgCl2 in ca. 80% yield. In an alternative route, 2 can be obtained from 1,8-naphthalenediyldiboric acid anhydride and HgCl2 in 85% yield. The structure of 2·DMSO has been determined by X-ray diffraction methods. The lattice contains discrete adducts in which the two mercury atoms are bridged by the DMSO oxygen atom. The HgCl moieties are bent away from each other through distortions of the naphthalene framework and of the C—Hg—Cl axes, which results in a Hg ‥ Hg distance of 3.102(1) Å. - Symmetrization of 2, induced by treatment with NaI in aqueous ethanol, affords bis(μ-1,8-naphthalenediyl)dimercury (3). In the X-ray structure determination of this compound the shortest „non-bonding“ Hg·Hg contact reported in the literature has been detected: Hg1··Hg2 = 2.797(1) Å. The molecule also shows distortions in the naphthalene framework and in the C—Hg—C axes [C—Hg—C = 173.3(5)°].
    Notes: 1-Naphthylquecksilberchlorid (1) und 1,8-Naphthalindiylbis-(quecksilberchlorid) (2) werden aus den zugehörigen Naphthyllithium-Verbindungen und HgCl2 mit ca. 80% Ausbeute erhalten. Alternativ kann 2 auch aus 1,8-Naphthalindiyldiborsäureanhydrid und HgCl2 gewonnen werden (Ausbeute 85%). Von 2·DMSO wurde die Kristallstruktur bestimmt. Es liegen diskrete Addukte vor, in denen die beiden Hg-Atome durch das O-Atom des DMSO überbrückt werden. Die HgCl-Einheiten sind durch Verzerrungen im Naphthalingerüst, durch Winkelung der Achsen C—Hg—Cl und durch deren Auslenkung aus der Naphthalinebene voneinander weggebogen, so daß ein Hg·· Hg-Kontakt von 3.102(1) Å resultiert. - 2 symmetrisiert sich bei der Einwirkung von NaI in wäßrigem Ethanol unter Bildung von Bis(μ-1,8-naphthalindiyl)diquecksilber (3). Bei der Strukturanalyse dieser im Kristall zentrosymmetrischen Verbindung wurde der bisher kürzeste „nichtbindende“ Hg··Hg-Kontakt von 2.797(1) Å gefunden. Auch in 3 sind die C—Hg—C-Achsen abgewinkelt [C—Hg—C = 173.3(5)°], und das Naphthalingerüst ist verzerrt.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 41
    Electronic Resource
    Electronic Resource
    Notizen N-Butyl-N′-dansylthioharnstoff als fluoreszierender Breitbandkomplexbildner (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 59-61 
    Details
    ISSN: 0009-2940
    Keywords: N-Butyl-N′-dansylthiourea ; Complexing agent, fluorescent ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-Butyl-N′-dansylthiourea as Fluorescent Broad-Band Complexing AgentN-Butyl-N′-dansylthiourea (2) [dansyl = 5-(dimethylamino)-1-naphthylsulfonyl] is obtained by the reaction of dansylamide (1) with butyl isothiocyanate. The compound is a stable, fluorescent complex agent for a broad spectrum of metal ions. The UV spectra and fluorescence of the ligand and some metal complexes are discussed. The fluorescence of the dansyl group is strongly affected by metal ions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220110
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 42
    Electronic Resource
    Electronic Resource
    Synthesis and Structure of Enaminecarbaldehydes and Enamino Ketones (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 83-94 
    Details
    ISSN: 0009-2940
    Keywords: Enaminecarbaldehydes ; Enamino ketones ; hetero Diels-Alder reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese und Struktur von Enaminecarbaldehyden und Enamino KetonenDie Synthese der Enamincarbaldehyde 1a-s und 17a-c sowie der Enamino-Ketone 2a-k und deren N-Acyl-Derivate 19a-k und 21-t mit Elektronenacceptor-Substituenten an C-2 bzw an der CO-Gruppe wird beschrieben. Kondensation von 2-Formyl-3-oxopropansäure-methylester (13) mit Ammoniak und den Aminen 14b-s ergab die Enamincarbaldehyde 1a bzw. 1b-s in einer Ausbeute von 72-93%. Die Enamincarbaldehyde 17 konnten durch Formylierung von 15 mit dem gemischten Ameisensäureessigsäureanhydrid erhalten werden. Die Synthese der Enamino-Ketone 2a-k erfolgte mit einer Ausbeute von 61-97% durch Kondensation von Ammoniak und Aminen mit den Enolethern 24a-f, die durch Umsetzung reaktiver Acylchloride 23 mit Ethylvinyl-ether dargestellt wurden. Die für hetero-Diels-Alder-Reaktionen benötigten N-Acyl-Derivate 19a-k und 21-t wurden durch Acylierung des Enamincarbaldehyds 1a und der Enamino-Ketone 2a-k gebildet.
    Notes: The synthesis of enaminecarbaldehydes 1a-s and 17a-c as well as enamino ketones 2a-k, and their N-acyl derivatives 19a-k and 21-t with electron accepting substituents at C-2 and at the CO group, respectively, is described. Condensation of methyl 2-formyl-3-oxopropanoate (13) with ammonia and the amines 14b-s gave the enaminecarbaldehydes 1a and 1b-s, respectively, in 72-93% yield. The enaminecarbaldehydes 17 were obtained by formylation of 15 with acetic formic anhydride. The synthesis of the enamino ketones 2a-k was accomplished in 61-97% yield by reaction of ammonia and amines with the enol ethers 24a-f, which were formed by treatment of reactive acyl chlorides 23 with ethyl vinyl ether. The enaminecarbaldehyde 1a as well as the enamino ketones 2a-k could be acylated to give 19a-k and 2l-t, respectively, which can be used in the hetero Diels-Alder reaction.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220114
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 43
    Electronic Resource
    Electronic Resource
    Chemie der Triphenyl-(oder Tri-n-butyl-)pyridylphosphoniumsalze, 2. 2,4-Pyridindiylbis(phosphoniumsalze) (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 119-122 
    Details
    ISSN: 0009-2940
    Keywords: Bis(phosphonium) salts ; Pyridylphosphonium salts, tri-n-butyl- and triphenyl- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chemistry of Triphenyl-(or Tri-n-butyl-)pyridylphosphonium salts, 2. - 2,4-Pyridinediylbis(phosphonium) Salts2,4-Pyridinediylbis(phosphonium) salts 1 react with nucleophiles to give 4-substituted products 6-8. Under radical reaction conditions the 5-position in 1a is attacked to yield 9. sodium azide transforms 1a into 8. This salt is used as starting material for 11. The removal of the phosphonium groups in 1 and in the resulting products can be carried out selectively.
    Notes: 2,4-Pyridindiylbis(phosphoniumsalze) 1 lassen sich mit nucleophilen Reaktionspartnern in die 4-substituierten Produkte 6-8 überführen. Unter radikalischen Bedingungen wird selektiv die 5-Position in 1a unter Bildung von 9 angegriffen. Nach Umsetzung mit Natriumazid entsteht zunächst das Salz 8, das als Ausgangsverbindung für 11 dient. Die Substitution der Phosphoniumgruppen aus den Edukten 1 und Produkten kann selektiv durchgeführt werden.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220119
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 44
    Electronic Resource
    Electronic Resource
    Ozonolysen von 1-Methylcyclopenten, 1-Methylcyclobuten, 5-Hexen-2-on und Naturkautschuk im Beisein von Methanol (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 145-149 
    Details
    ISSN: 0009-2940
    Keywords: Cycloalkenes, 1-methyl- ; Ozonolysis ; Peroxyhemiacetals, cyclic ; Rubber, natural ; Tetrahydrofurans, 2-hydroperoxy- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ozonolyses of 1-Methylcyclopentene, 1-Methylcyclobutene, 5-Hexen-2-one and Natural Rubber in the Presence of MethanolOzonolyses of 1-methylcyclopentene (8a) and of 1-methylcyclobutene (8b) in methanol proceeded in each case in the two possible directions. The resulting methoxyperoxides 13 and 14 afforded the corresponding peroxyhemiacetals 15 and 19 by intramolecular reactions of the OOH with the corresponding carbonyl groups. Ozonolysis of 1-methylcyclobutene (8b) additionally gave the corresponding ozonide 17b and 2-hydroperoxy-5-methoxy-2-methyl-as well as 5-hydroperoxy-2-methoxy-2-methyltetrahydrofuran (16b and 18b). The mode of formation of these hydroperoxy compounds has been elucidated by ozonolyses of 5-hexen-2-one (25) and of natural rubber (28) in the presence of methanol.
    Notes: Ozonolysen von 1-Methylcyclopenten (8a) und von 1-Methylcyclobuten (8b) in Methanol verliefen jeweils nach beiden möglichen Spaltungsrichtungen. Die dabei gebildeten Methoxyhydroperoxide 13 und 14 ergaben durch intramolekulare Reaktionen der OOH- mit den Carbonylgruppen die entsprechenden Peroxyhalbacetale 15 bzw. 19. Bei der Ozonolyse von 1-Methylcyclobuten (8b) wurden zusätzlich das entsprechende Ozonid 17b sowie 2-Hydroperoxy-5-methoxy-2-methyl- und 5-Hydroperoxy-2-methoxy-2-methyltetrahydrofuran (16b und 18b) gebildet. Die Bildungsweise dieser Hydroperoxy-Verbindungen wurde durch Ozonolysen von 5-Hexen-2-on (25) und von Naturkautschuk (28) im Beisein von Methanol aufgeklärt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220123
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 45
    Electronic Resource
    Electronic Resource
    Synthese neuer 3-substituierter Pyrrole (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 169-174 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of New 3-substituted PyrrolesThe synthesis of 3-alkyl- (4), 3-(ω-bromoalkyl)- (5), 3-iodo- (6), 3-formyl- (9a), 3-acetyl-1-(triisopropylsilyl)pyrrole (9b), of 2-[1-(triisopropylsilyl)-3-pyrrolyl]-2-propanol (7), 1-(triisopropylsilyl)-3-pyrrolecarboxylic acid (8), and 7-[1-(triisopropylsilyl)-3-pyrrolyl]heptanoic acid (10) as well as the desilylation of these products to the corresponding 3-substituted pyrroles 11 is described. Intermediates in these syntheses are 1-(triisopropylsilyl)pyrrole (1), 3-bromo- (2), and 3-lithio-1-(triisopropylsilyl)pyrrole (3).
    Notes: Die Synthese von 3-Alkyl- (4), 3-(ω-Bromalkyl)- (5), 3-Iod- (6), 3-Formyl- (9a) und 3-Acetyl-1-(triisopropylsilyl)pyrrol (9b), von 2-[1-(Triisopropylsilyl)-3-pyrrolyl]-2-propanol (7), 1-(Triisopropylsilyl)-3-pyrrolcarbonsäure (8) und 7-[1-(Triisopropylsilyl)-3-pyrrolyl]heptansäure (10) sowie die Desilylierung dieser Produkte zu den entsprechenden 3-substituierten Pyrrolen 11 wird beschrieben. Zwischenstufen der Darstellung sind 1-(Triisopropylsilyl)pyrrol (1), 3-Brom- (2) und 3-Lithio-1-(triisopropylsilyl)pyrrol (3).
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220126
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 46
    Electronic Resource
    Electronic Resource
    Masthead (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 47
    Electronic Resource
    Electronic Resource
    Übergangsmetall-Silyl-Komplexe, 26. Gold(I)-Silyl-Komplexe (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 223-230 
    Details
    ISSN: 0009-2940
    Keywords: Gold(I) silyl complexes ; Transition-metal silyl complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition-Metal Silyl Complexes, 26. - Gold(I) Silyl ComplexesComplexes of type L-Au-SiR3 with L = PR′3 or PhNC and SiR3 = Si(aryl)3, Si(SiMe3)3, or SiPh2Me are prepared by reaction of L-Au-Cl with LiSiR3. Depending on L and R, their stability decreases, in the order R′3P-Au-Si(aryl)3 〉 R′3P-Au-Si(SiMe3)3 〉 R′3P-Au-SiPh2Me ≈ PhNC-Au-SiR3. Reaction of R′3P-Au-CH3 or R′3P-Au-OAc with HSiR3 does not yield silyl complexes. However, using chlorinated silanes like HSiR2Cl, CH3/Cl or OAc/Cl exchange takes place. The Mössbauer spectrum of MePh2P-Au-SiPh3 (6) and NMR- and IR-spectroscopic investigations show that silyl groups act as strong σ donors towards the gold atom. MePh2P-Au-SiPh3 (6) and MePh2P-Au-Si(SiMe3)3 (7) have been characterized by X-ray structure analyses [Au—Si 235.4(4) and 235.6(2) pm]. The Au-Si bond in MePh2P-Au-SiPh2Tol (5) is cleaved by X2 (X = Cl, Br, I), HCl or MeI, but not by H2O or MeOH.
    Notes: Komplexe des Typs L-Au-SiR3 mit L = PR′3 oder PhNC und SiR3 = Si(aryl)3, Si(SiMe3)3 oder SiPh2Me wurden durch Umsetzung von L-Au-Cl mit LiSiR3 dargestellt. Ihre Stabilität sinkt in Abhängigkeit von L und R in der Reihenfolge R′3P-Au-Si(aryl)3 〉 R′3P-Au-Si(SiMe3)3 〉 R′3P-Au-SiPh2Me ≈ PhNC-Au-SiR3. Umsetzung von R′3P-Au-CH3 oder R′3P-Au-OAc mit HSiR3 ergibt keine Silyl-Komplexe, bei Verwendung chlorierter Silane, HSi-R2Cl, findet lediglich CH3/Cl- bzw. OAc/Cl-Austausch statt. Das Mößbauer-Spektrum von MePh2P-Au-SiPh3 (6) sowie NMR- und IR-spektroskopische Untersuchungen zeigen, daß Silylreste als starke σ-Donor-Liganden gegenüber dem Goldatom wirken. MePh2P-Au-SiPh3 (6) und MePh2P-Au-Si(SiMe3)3 (7) wurden durch Röntgenstrukturanalysen charakterisiert [Au—Si 235.4(4) und 235.6(2) pm]. Die Au—Si-Bindung in MePh2P-Au-SiPh2 Tol (5) wird durch X2 (X = Cl, Br, I), HCl oder MeI, nicht aber durch H2O oder MeOH gespalten.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 48
    Electronic Resource
    Electronic Resource
    Reaktionen von Germylenen mit Aziden: Iminogermane, Azidogermane, Tetrazagermole und Hexaazadigermadispirododecane (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 245-252 
    Details
    ISSN: 0009-2940
    Keywords: Germylenes ; Germanium nitrogen compounds ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Germylenes with Azides: Iminogermanes, Azidogermanes, Tetrazagermoles and HexaazadigermadispirododecanesGermylenes, X2Ge, stabilized by steric blocking and/or incorporation into five-membered ring systems, react with azido compounds YN3 depending on the steric requirements of the substituents X and Y to give iminogermanes, X2Ge=NY (1, 2) azidogermanes X2Ge(N3)NY2 (6-8) tetrazagermoles, X2Ge(— NY — N =)2 (10-16), and hexaazadigermadispirododecanes, [(— NR — CH2 — CH2 — NR —)Ge(μ-NY -)]2 (17, 18). NMR (1H, 13C, 14N, 15N, and 29Si), MS data, and X-ray structure analyses of the compounds 8, 9, 16, and 18 are reported.
    Notes: Durch sterische Blockierung und/oder Einbau in fünfgliedrige Ringsysteme stabilisierte Germylene, X2Ge, reagieren mit Azidoverbindungen, YN3, in Abhängigkeit von der Raumerfüllung der Substituenten X und Y zu Iminogermanen X2 Ge=NY (1, 2), Azidogermanen, X2Ge(N3)NY2 (6′8), Tetrazagermolen, X2Ge-(-NY-N=)2 (10-16), bzw. Hexaazadigermadispirododecanen, [(—NR—CH2—CH2—NR— )Ge(μ-NY-)]2 (17, 18). NMR-(1H, 13C, 14N, 15N und 29Si), MS-Daten und Röntgenstrukturanalysen für die Verbindungen 8, 9, 16 und 18 sind angegeben.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220206
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 49
    Electronic Resource
    Electronic Resource
    (Trifluormethyl)germane, III. Darstellung neuer (Trifluormethyl)germanium-Chalkogen-Verbindungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 271-277 
    Details
    ISSN: 0009-2940
    Keywords: Chalcogenogermanes, (trifluoromethyl)- ; Disilaselenanes ; Germachalcogenanes, bis(trifluoromethyl)- ; Germanes, (trifluoromethyl)- ; Germatranes, (trifluoromethyl)- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: (Trifluormethyl)germanes, III. - Preparation of New (Trifluormethyl)germanium Chalcogene CompoundsStarting with the dihalogenobis(trifluoromethyl)germanes (CF3)2-GeX2 (X = Cl, or I), halogen-chalcogen exchange leads to corresponding chalcogen derivatives of the general type [(CF3)2GeE]n (6, 7) (E = O, NH, S, or Se). The resulting compounds differ in their degree of polymerisation. [(CF3)2GeO]x and the corresponding sesquioxane [(CF3)GeO1, 5]x are highly polymeric, quite in contrast to the corresponding germathianes and -selenanes. The crystal structure of [(CF3)2GeO]x (6a) was determined by X-ray single crystal diffraction. The reaction of CF3GeCl3 with triethanolamine results in the formation of 1-(trifluoromethyl)germatrane (13). Disilaselenane (10) reacts at low temperatures with chloro-(trifluoromethyl)germanes (CF3)nGeCl4-n under retention of one Si—Se bond to give (CF3)nGe(SeSiH3)4-n (11) and H3SiCl. Compounds with n = 3 and 2 could be isolated. Exchange of iodine by ECF3 takes place with iodogermanes (CF3)nGeI4-n and Hg(ECF3)2 (E = S, Se) with formation of a complete series of (trifluoromethyl)(trifluoromethylchalcogeno)germanes (CF3)nGe-(ECF3)4-n (3, 5).
    Notes: Durch Halogen-Chalkogen-Austauschreaktionen an (CF3)2)GeX2 (X = Cl, I) wurden Bis(trifluormethyl)germachalkogenane [(CF3)2GeE]n (6, 7) E = O, NH, S, Se) von unterschiedlichem Oligomerisierungsgrad erhalten. Die Germoxane [(CF3)2GeO]x und (CF3GeO1,5)x sind im Gegensatz zu den homologen Germathianen und -selenanen polymer, wobei die Struktur von [(CF3)2GeO]x (6a) durch eine Kristallstrukturanalyse ermittelt wurde. Durch Umsetzung von CF3GeCl3 mit Triethanolamin wird 1-(Trifluormethyl)germatran (13) erhalten. Disilaselenan (10) reagiert bei tiefen Temperaturen mit den Chlor (trifluormethyl)-germanen (CF3)nGeCl4-n monofunktionell unter Erhalt einer Si—Se-Bindung zu (CF3)nGe(SeSiH3)4-n (11) und H3SiCl, von denen die Verbindungen mit n = 3 und 2 isoliert werden konnten. Reaktionen der Iodgermane (CF3)nGeI4-n(1) mit Hg(ECF3)2) (E = S, Se) führen unter Substitution des Iods gegen die ECF3-Gruppen zur vollständigen Reihe der (Trifluormethyl)(trifluormethylchalkogeno)germane (CF3)nGe(ECF3)4-n (3, 5).
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 50
    Electronic Resource
    Electronic Resource
    Synthesis and Properties of a (Phthalocyaninato)copper(II) Complex Symmetrically Substituted with Eight Crown Ethers (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 291-292 
    Details
    ISSN: 0009-2940
    Keywords: (Phthalocyaninato)copper complex, substituted with crown ethers ; Alkali metal extraction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A soluble (phthalocyaninato)copper(II) complex containing eight symmetrical benzo-15-crown-5 substituents, namely {2,3,9,10,16,17,23,24-octakis[[benzo-15-crown-5)-4′ -yl]oxymethyl]phthalocyaninato}copper(II) (2) from 1,2-bis{[benzo-15-crown-5)-4′-yl]oxymethyl}-4,5-dibromobenzene (1) and CuCN in quinoline or pyridine was synthesized. The crown-ether groups in 2 were shown to prefer intramolecular complexation with alkali metal ions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220214
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 51
    Electronic Resource
    Electronic Resource
    Sterische Hinderung der C—C-Rotation durch zwei SF5-Gruppen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 463-466 
    Details
    ISSN: 0009-2940
    Keywords: C—C Rotation ; Sterical hindrance by SF5 groups ; Rotational barriers ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sterical Hindrance of the C—C Rotation by two SF5 GroupsAddition of SF5Cl to SF5CH=CF2 gives products carrying two SF5 groups on one carbon atom. As a consequence, C—C single bond rotation is strongly hindered. The highest rotational barrier observed is 61.7 kJ mol-1, rotational isomers are hence detectable at room temperature.
    Notes: Die Addition von SF5Cl an SF5CH=CF2 ergibt Produkte, die zwei SF5-Gruppen an einem Kohlenstoff tragen. In diesen kommt es zu einer starken Hinderung der Rotation um die C—C-Einfachbindung. Die höchste Rotationsbarriere wird mit 61.7 kJ mol-1 gefunden, d. h. Rotationsisomere sind bei Raumtemperatur getrennt nachweisbar.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 52
    Electronic Resource
    Electronic Resource
    Synthese, Struktur und Reaktionen von 1,2,3,6-Tetrahydro-1,2,3,6-diphosphadiborin-Derivaten (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 467-472 
    Details
    ISSN: 0009-2940
    Keywords: Tetracarbonylchromium complexes ; 1,2,3,6-Tetrahydro-1,2,3,6-diphosphadiborine derivatives ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Structure, and Reactions of 1,2,3,6-Tetrahydro-1,2,3,6-diphosphadiborine DerivativesThe 1,2,3,6-tetrahydro-1,2,3,6-diphosphadiborine derivatives 3a and 3b are obtained by cyclocondensation of 1,2-bis[chloro(dialkylamino)boryl]ethenes 2 and 1,2-dipotassium 1,2-di-tert-butyldiphosphanediide. As in the case of 2,5-dihydro-1H-1,2,5-phosphadiborole derivatives 1 the temperature-dependent 1H-NMR spectra of 3b exhibit a lowered barrier of inversion at phosphorus. The X-ray structure analysis of 3b shows, that the six-membered C2B2P2 ring is nonplanar and the P atoms are coordinated pyramidally. Attempts to substitute the dialkylamino groups at the boron atoms of 3a and 3b with HCl·Et2O or tBuLi lead to cleavage of the B—P bonds. Reaction between 3a or 3b and Cr(CO)3(MeCN)3 does not result in the formation of tricarbonylchromium complexes but of tetracarbonylchromium complexes 6a and 6b with pentahapto-bonded ligands 3a and 3b.
    Notes: Die 1,2,3,6-Tetrahydro-1,2,3,6-diphosphadiborin-Derivate 3a und 3b entstehen durch Cyclokondensation aus 1,2-Bis[chlor(dialkylamino)boryl]ethenen 2 und 1,2-Dikalium-1,2-di-tert-butyldiphosphandiid. Die Temperaturabhängigkeit der 1H-NMR-Spektren von 3b dokumentiert wie bei 2,5-Dihydro-1H-1,2,5-phosphadiborol-Derivaten 1 eine erniedrigte Phosphor-Inversionsbarriere. Die Röntgenstrukturanalyse von 3b zeigt, daß der C2B2P2-Sechsring im Kristall nicht eben ist und daß die P-Atome pyramidal koordiniert sind. Versuche zur Substitution der Dialkylaminogruppen an den Boratomen von 3a und 3b mit HCl·Et2O oder tBuLi führen zur Spaltung der B—P-Bindungen. Die Umsetzung von 3a bzw. 3b mit Cr(CO)3(MeCN)3 ergibt keine Tricarbonylchrom-Komplexe, sondern die Tetracarbonylchrom-Komplexe 6a bzw. 6b, in denen die Liganden 3a und 3b pentahapto gebunden sind.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220312
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 53
    Electronic Resource
    Electronic Resource
    Organische Synthesen mit Übergangsmetallkomplexen, 34 Neuartiger Aufbau von C = C-Bindungen durch Kondensation von Carbenkomplexen mit Säureamiden unter Insertion von C2-Einheiten in M=C-Bindungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 365-370 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organic Synthesis via Transition Metal Complexes, 34. - Novel Formation of C=C Bonds by Condensation of Acid Amides with Carbene Complexes Involving an Insertion of C2 Units into M=C BondsCarben complexes LnM=C(OEt)C6H5 1 [LnM = Cr(CO)5, Mo(CO)5, W(CO)5] and acid amides RCH2CONMe2 2 undergo a novel condensation reaction in presence of POCl3/Et3N to give alkenyl aminocarbene complexes 3. The reaction involves an insertion of a C2 unit of 2 into the M=C bond of 1 to give a C=C bond. It can be achieved with open-chain and cyclic amides like N-methyl-2-pyrrolidone (8). the structures of the complexes have been determined spectroscopically. A mechanism of the reaction is suggested.
    Notes: Carbenkomplexe LnM=C(OEt)C6H5 1 [LnM = Cr(CO)5, Mo(CO)5, W(CO)5] lassen sich mit Säureamiden RCH2CONMe2 2 und POCl3/Et3N zu Alkenyl-Aminocarben-Komplexen 3 kondensieren. Dabei wird eine C2-Einheit von 2 in die M=C-Bindung von 1 eingeschoben und eine C=C-Bindung neu geknüpft. Die Reaktion gelingt mit offenkettigen und cyclischen Amiden wie N-Methyl-2-pyrrolidon (8). Die Strukturen der Komplexe wurden spektroskopisch ermittelt und Vorschläge zur Deutung des Reaktionsablaufs gemacht.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220226
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 54
    Electronic Resource
    Electronic Resource
    Azulen und 1,6-Methano[10]annulen als Dienophile in der Diels-Alder-Reaktion mit 3,6-Bis(trifluormethyl)-1,2,4,5-tetrazin (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 711-714 
    Details
    ISSN: 0009-2940
    Keywords: Azulenes ; 1,6-Methano[10]annulenes ; 1,2,4,5-Tetrazine ; [4 + 2] Cycloadditions, „inverse“ ; Pyridazines, annulated ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Azulene and 1,6-Methano[10]annulene as Dienophiles in the Diels-Alder Reaction with 3,6-Bis(trifluoromethyl)-1,2,4,5-tetrazineThe LUMO-diene-controlled [4 + 2] cycloadditions of azulene (2) and 1,6-methano[10]annulene (14) with the electron-deficient s-cisfixed diazadiene system of 3,6-bis(trifluoromethyl)-1,2,4,5-tetrazine (1) are described. Contrary to expectation, 1 reacts under unusually mild conditions with 2 (or its valence tautomer 3) to yield the adduct 4 which after N2 elimination rearranges to the benzo[f]phthalazine 11. The Diels-Alder reaction of 1 with 14 (or its valence tautomer 13) leads to the annulated dihydropyridazines 15 and 16, which can be dehydrogenated by silver(I) oxide to the methano-bridged aromatic cyclodecapyridazine 17 and the olefinic phthalazino[5,6-f]phthalazine 18, respectively. Besides, the methano-bridged cyclodeca[d]pyridazine 24 is prepared.
    Notes: LUMO-Dien-kontrollierte [4 + 2]-Cycloadditionen von Azulen (2) und 1,6-Methano[10]annulen (14) an das elektronenarme, s-cis-fixierte Diazadiensystem von 3,6-Bis(trifluoromethyl)-1,2,4,5-tetrazin (1) werden beschrieben. Wider Erwarten reagiert 1 unter ungewöhnlich milden Bedingungen mit 2 (oder dessen Valenztautomerem 3) zum Addukt 4, das nach N2-Eliminierung und nachfolgender Umlagerung das Benzo[f]phthalazin 11 liefert. Die Diels-Alder-Reaktion von 1 mit 14 (oder dessen Valenztautomer 13) führt zu den beiden anellierten Dihydropyridazinen 15 und 16, die mit Silber(I)-oxid zu dem Methano-überbrückten aromatischen Cyclodecapyridazin 17 bzw. dem olefinischen Phthalazino[5,6-f]phthalazin 18 dehydriert werden können. Daneben wird das Methano-überbrückte Cyclodeca[d]pyridazin 24 dargestellt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220418
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 55
    Electronic Resource
    Electronic Resource
    On the Thermal Cycloisomerization of Long-Chain Alkylacetylenes in the Gas Phase (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 715-719 
    Details
    ISSN: 0009-2940
    Keywords: Alkyne ; Carbene ; Cycloisomerization ; Pyrolysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Über die thermische Cycloisomerisierung langkettiger Alkylacetylene in der GasphaseDie thermische Cycloisomerisierung einiger Alkylacetylene wurde in einem Laborrohrreaktor aus Quarzglas untersucht. 1-Hexin (1) wird dabei durch 1,2-H-Verschiebung und 1,5-C,H-Insertion des intermediär gebildeten Pentylidencarbens (vgl. Schema 1) in 3-Methyl-1-cyclopenten (5) umgelagert. 5-Methyl-1-hexin (2) reagiert analog; es entsteht 3,3-Dimethyl-1-cyclopenten (6). Im Gegensatz zur Bildung von in 3-Stellung methylierten Cyclopentenen aus 1-Alkinen ensteht aus 2-Hexin (3) 1-Methyl-1-cyclopenten (7). Offenbar ist die Acetylen-Vinyliden-Umlagerung nicht auf 1,2-H-Verschiebung beschränkt. Der Mechanismus der Cycloisomerisierung von Alkylacetylenen wird durch Untersuchungen mit D-markierten Alkinen bestätigt. Die Ergebnisse lassen den Schluß zu, daß die Cycloisomerisierung ohne weiteres mit dem überwiegend nach einem Radikalketten-Mechanismus verlaufenden thermischen Zerfall konkurrieren kann.
    Notes: The thermal cycloisomerization of some alkylacetylenes was investigated in a tubular quartz reactor. At 570°C 1-hexyne (1) rearranges to 3-methyl-1-cyclopentene (5) with a selectivity of about 27 by a reaction sequence including an acetylene-vinylidene rearrangement and 1,5-C,H insertion of the intermediately formed alkylidenecarbene species. 5-methyl-1-hexyne (2) behaves analogously forming 3,3-dimethyl-1-cyclopentene (6), while 2-hexyne (3) provides 1-methyl-1-cyclopentene (7) indicating that the acetylene-vinylidene rearrangement is obviously not restricted to 1,2-H shifts. The mechanism of the cycloisomerization of alkylacetylenes is investigated by means of D-labeled parent alkynes. The results show that the unimolecular cycloisomerization via alkylidenecarbenes obviously can be an important channel despite the dominance of a radical chain course.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220419
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 56
    Electronic Resource
    Electronic Resource
    Methoxy- and Aminoisocyanate (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 745-748 
    Details
    ISSN: 0009-2940
    Keywords: Flash Pyrolysis ; Matrix IR spectroscopy ; Photolysis ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Methoxy- und AminoisocyanatMethoxyisocyanat (1) kann durch Photolyse von Azidoameisensäure-methylester (3) oder Pyrolyse von N-Methoxycarbonyl-O-methylhydroxylamin (4) dargestellt werden. Aminoisocyanat (2) ist auf ähnliche Weise durch Photolyse von Carbamoylazid (12) und Pyrolyse von Carbazinsäure-methylester (13) oder 3,4-Diaminofurazan (14) zugänglich. Die IR-Spektren von 1 und 2, aufgenommen in einer Argon-Matrix bei 10 K, werden diskutiert.
    Notes: Methoxyisocyanate (1) can be prepared by photolysis of methyl azidoformate (3) or pyrolysis of N-methoxycarbonyl-O-methyl-hydroxylamine (4). Aminoisocyanate (2) is similarly formed on photolysis of carbamoyl azide (12) and pyrolysis of either methyl carbazate (13) or 3,4-diaminofurazan (14). The infrared spectra of 1 and 2 in an argon matrix at 10 K have been measured, and some of their properties are discussed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220423
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 57
    Electronic Resource
    Electronic Resource
    Infrared Spectra and Photochemistry of Isodiazene and Its Deuterated Isotopomers (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 749-752 
    Details
    ISSN: 0009-2940
    Keywords: Matrix isolation ; Photochemistry ; Theoretical vibrational spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Infrarot-Spektren und Photochemie von Isodiazen und seinen deuterierten IsotopomerenDie Matrixisolation von Aminoisocyanat eröffnet einen neuen ergiebigen Weg zur Darstellung von Isodiazen (Aminonitren). Damit ist es möglich geworden, nicht nur sein IR-Spektrum eindeutig festzulegen und mit Hilfe von ab-initio-Rechnungen zu interpretieren, sondern auch seine Photochemie zu untersuchen.
    Notes: The matrix isolation of aminoisocyanate opens a new efficient route for the preparation of isodiazene (aminonitrene). Its infrared spectrum can now, with the help of ab initio calculations, be interpreted, and its photochemistry can be studied.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220424
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 58
    Electronic Resource
    Electronic Resource
    Further Thienylchalcones, II (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 795-796 
    Details
    ISSN: 0009-2940
    Keywords: Thiochalcones ; Thienylchalcones ; Fries rearrangement ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four new thienylchalcones (1, 4, 5, and 6) were synthesized by condensing hydroxy-nitroacetophenones with 2-thiophene and 3-thiophenecarboxaldehydes in the presence of dilute NaOH.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220428
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 59
    Electronic Resource
    Electronic Resource
    Valenzisomerisierungen, 17. Persubstituierte cis-9,10-Dihydronaphthaline und ihre Valenzisomerisierungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 767-779 
    Details
    ISSN: 0009-2940
    Keywords: Molecular twisting ; cis-9,10-Dihydronaphthalenes, persubstituted ; Valence isomerizations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Valence Isomerizations, 17. - Persubstituted cis-9,10-Dihydronaphthalenes and their Valence IsomerizationsThe tricyclic diester 10 is available from 2-butyne in a six-step synthesis with an overall yield of 10%. Thermolysis of 10 gives the bicyclic diester 11 which upon UV irradiation yields 12 as the first persubstituted cis-9,10-dihydronaphthalene. X-ray analysis of 12 shows the molecule considerably twisted along the central bond. In addition, the planes of the ester groups are at an angle of approximately 60° to the „planes“ of the six-membered rings so that conjugation of the diene systems with the carbonyl functions is virtually interrupted, an effect which is reflected by the unusual spectroscopic properties of 12. The same structural features can be found in decamethyl-cis-9,10-dihydronaphthalene (16). When heated slightly, 12 is converted to the tetracyclic valence isomer 34. On reduction of 12 with diisobutylaluminum hydride both, dihydronaphthalene dicarbinol 25 as well as its unexpected positional isomer 26, are formed depending on the reaction conditions. Etherification of the reduction products with CH2N2/Et2O—BF3 furnishes a mixture of the three isomeric bis(methoxymethyl) compounds 31, 32 and 33. They can be separated by chromatography in the cold, but revert to the mixture of the three isomers at room temperature. We consider diradical 38 to be the intermediate of this intriguing valence isomerization.
    Notes: Der tricyclische Diester 10 ist in sechs Stufen in einer Gesamtausbeute von 10% aus 2-Butin zugänglich. Thermolyse von 10 liefert den Bicyclus 11, bei dessen UV-Bestrahlung das erste persubstituierte cis-9,10-Dihydronaphtalin 12 gebildet wird. Eine Röntgenstrukturanalyse von 12 beweist die starke Verdrillung des Moleküls um die zentrale Bindung. Die Ebenen der Ester-Gruppen stehen ungefähr in einem 60°-Winkel zu den Sechsring-„Ebenen“, so daß die Konjugation der Dien-Systeme mit den Carbonyl-Funktionen praktisch unterbrochen ist, ein Effekt, der sich in den ungewöhnlichen spektroskopischen Eigenschaften von 12 widerspiegelt. Analoge Strukturmerkmale gelten auch für das Decamethyl-cis-9,10-dihydronaphthalin (16). Bicyclus 12 wandelt sich bei leichtem Erwärmen in den valenzisomeren Tetracyclus 34 um. Reduktion von 12 mit Diisobutylaluminiumhydrid gibt je nach den Reaktionsbedingungen das Dihydronaphthalindicarbinol 25 bzw. das unerwartete Stellungsisomere 26. Veretherung der Reduktionsprodukte mit CH2N2/Et2O—BF3 liefert ein Gemisch der drei isomeren Bis(methoxymethyl)-Verbindungen 31, 32 und 33, die chromatographisch in der Kälte trennbar sind, aber schon bei Raumtemperatur wieder das Gemisch der drei Isomeren zurückbilden, wobei das Diradikal 38 als Zwischenprodukt dieser erstaunlichen Valenzisomerisierung anzunehmen ist.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220426
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 60
    Electronic Resource
    Electronic Resource
    Strukturen von Pentaarylbismut-Verbindungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 803-808 
    Details
    ISSN: 0009-2940
    Keywords: Bismuth organic compounds ; Fluorinated aromatic rings ; Square pyramidal bismuth ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structures of Pentaarylbismuth CompoundsPentaarylbismuth compounds were synthesized by the known reaction Ar3BiX2 + 2 Ar′Li → 2 LiX + BiAr3Ar′2. Whenever possible they were characterized by single-crystal X-ray structure determination. In two cases almost ideal square-pyramidal geometry was found, in a third case there were two different molecules in the unit cell, both again with square-pyramidal geometry. None of these novel bismuth pentaaryls exhibit the deep coloration and the dichroism of Bi(C6H5)5.
    Notes: Pentaarylbismut- Verbindungen wurden durch die bekannte Reaktion BiAr3X2 + 2 Ar′Li → 2 LiX + BiAr3Ar′2 hergestellt und, soweit möglich, durch Röntgenbeugung an Einkristallen strukturell untersucht. In zwei Fällen erwies sich die Struktur als nahezu ideal quadratisch-pyramidal, in einem dritten Fall wurden zwei unterschiedliche Moleküle im Kristall gefunden, die aber beide wiederum quadratisch-pyramidal sind. Keines der hier vorgestellten neuen Bismutpentaaryle zeigt die tiefe Färbung und den Dichroismus von Bi(C6H5)5.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 61
    Electronic Resource
    Electronic Resource
    Über sterisch gehinderte freie Radikale, XIX. Stabile 4,4′,4″-trisubstituierte Triphenylmethyl-Radikale (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 533-535 
    Details
    ISSN: 0009-2940
    Keywords: Free radicals ; Triphenylmethyl radicals ; ESR measurements ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sterically Hindered Free Radicals, XIX. - Stable 4,4′,4″-Trisubstituted Triphenylmethyl RadicalsThe title radicals (4-R—C6H4)3C. (1), R = F, Cl, Ph, OMe, NO2, tBu, OEt, SMe, CN, CF3, have been prepared, the latter four for the first time, and the ESR spectra have been recorded. aoH, amH, and apR are listed. The intensities of the ESR signals remain constant within the accessible range of -30 to + 100°C. Within this range these radicals are kinetically stable and do not dimerize like other trityls by, e.g., α,p-, α,o-, α,α -recombinations.
    Notes: Die Titelradikale (4-R—C6H4)3C· (1), R = F, Cl, Ph, OMe, NO2, tBu, OEt, SMe, CN, CF3, wurden dargestellt, davon die vier letzten erstmalig, und mittels ESR-Spektroskopie vermessen. aoH, amH und apR werden angegeben. Die ESR-Signale bleiben im gesamten zugänglichen Temperaturbereich - 30 bis + 100°C in ihrer Intensität unverändert. Daraus folgt, daß alle diese Radikale im genannten Temperaturbereich kinetisch stabil sind, also nicht wie andere Trityle zu Dimerisierungen, etwa α,p-, α,o-, α,α-, neigen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220322
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 62
    Electronic Resource
    Electronic Resource
    Neuartige Produkte der Weiss-Reaktion von 1,2-Cyclopentandion Verbesserte Herstellung von [3.3.3]Propellan-3,7-dion (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 523-531 
    Details
    ISSN: 0009-2940
    Keywords: Dicyclopenta-s-indacene ; 2-Osxa[3.3.3]propellane derivatives ; Pentalene derivatives ; [3.3.3]Propellane-3,7-dione ; Weiss reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Novel Products in the Weiss Reaction of 1,2-Cyclopentanedione. Improved Preparation of [3.3.3]Propellane-3,7-dioneThe reaction of 1,2-cyclopentanedione (1c, 9) with the 3-oxoglutarate 4 in methanol/water in the presence of sodium bicarbonate followed by hydrolysis and decarboxylation of the product mixture affords the oxa[3.3.3]propellane ester 11c in addition to the [3.3.3]propellanedione 6c. The alkali enolates of 4 react with 9 in boiling methanol to yield the yellow, poorly soluble alkali dihydropentalenolates 12M and the [3.3.3]propellane tetraester 5c, which on hydrolysis and decarboxylation yields 53% of 6c. The dihydropentalenol 12H equilibrates with the tautomeric β-oxodiester 13, the proportion of which increases with solvent polarity. In methanol solutions, 12H and 13 add diastereoselectively forming the dicyclopenta-s-indacene tetraester syn-14, which is derived from a novel pentacyclic ring system. The configuration of syn-14 is determined by X-ray diffraction analysis. The mechanisms of formation are discussed for 11c, 12M, and syn-14.
    Notes: Nach Umsetzung von 1,2-Cyclopentandion (1c, 9) mit dem 3-Oxoglutarsäureester 4 in Methanol/Wasser in Gegenwart von Natriumhydrogencarbonat, saurer Hydrolyse und Decarboxylierung des Produktgemischs erhält man neben dem [3.3.3]Propellandion 6c den Oxa[3.3.3]propellanester 11c. Die Alkali-Enolate von 4 reagieren mit 9 in siedendem Methanol zu den gelben, schwer löslichen Dihydropentalenolaten 12M und dem [3.3.3]Propellantetraester 5c, der nach Hydrolyse und Decarboxylierung 53% 6c ergibt. Das Dihydropentalenol 12H liegt im Gleichgewicht mit dem tautomeren β-Oxodiester 13 vor, dessen Anteil mit der Polarität des Lösungsmittels zunimmt. In Methanol addieren sich 12H und 13 diastereoselektiv und bilden den Dicyclopenta-s-indacentetraester syn-14, der sich von einem neuartigen, pentacyclischen Ringsystem ableitet. Die Konfiguration von syn-14 wird durch Röntgenstrukturbestimmung aufgeklärt. Die Mechanismen der Bildung von 11c, 12M und syn-14 werden diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220321
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 63
    Electronic Resource
    Electronic Resource
    Aminosäuren, 15. Diastereoselektive Addition von Thiocarbonsäuren an 1-(Methacryloyl)prolin- und -prolinol-Derivate (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 553-559 
    Details
    ISSN: 0009-2940
    Keywords: Amino acids ; Diastereoselective addition ; 1-(Methacryloyl)proline derivatives ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Amino Acids, 15. - Diastereoselective Addition of Thiocarboxylic Acids to 1-(Methacryloyl)proline and-prolinol DerivativesThiocarboxylic acids 6 add to 1-(methacryloyl)-substituted proline and prolinol derivatives stereoselectively to give the 1-[3-(acylthio)-2-methylpropionyl]proline and -prolinol derivatives 7,7′ and 9. The less soluble (2S,2′R)-diastereomers are obtained in optical yields ≥ 98% by digestion of the crude products, the configuration of which was determined by acid hydrolysis of (2S,2′R)-7,7′ to (R)-3-mercapto-2-methylpropionic acid [(R)-8]. The stereoselectivity of the additions may be explained by a sevenmembered ring intermediate with an intramolecular H bridge, to which the S-nucleophiles add preferentially to give the compounds with the (2′R)-configuration.
    Notes: Thiocarbonsäuren 6 addieren stereoselektiv mit hohen optischen Ausbeuten an 1-(Methacryloyl)-substituierte Prolin- und Prolinol-Derivate zu den 1-[3-(Acylthio)-2-methylpropionyl]prolin-und -prolinol-Derivaten 7,7′ und 9. Durch Digerieren der Rohprodukte mit Diethylether werden die schwerer löslichen (2S,2′R)-Diastereomeren in optischen Ausbeuten ≥98% erhalten, deren Konfiguration durch Acidolyse von (2S,2′R)-7,7′ zu (R)-3-Mercapto-2-methylpropansäure [(R)-8] bewiesen wurde. Die Stereoselektivität der Additionen wird über einen Siebenring mit intramolekularer H-Brücke als Zwischenstufe, an die Schwefelnucleophile bevorzugt unter Bildung der (2′R)-Konfiguration addieren, gedeutet.
    Additional Material: 10 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220325
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 64
    Electronic Resource
    Electronic Resource
    Aminosäuren, 14. Diastereoselektive Addition von Benzolsulfenylchlorid an 1-Acryloylprolinester (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 545-551 
    Details
    ISSN: 0009-2940
    Keywords: Amino acids ; Diastereoselective addition ; 1-Acryloylproline esters ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Amino Acids, 14. - Diastereoselective Addition of Benzenesulfenyl Chloride to 1-Acryloylproline Esters(S)-Proline esters (S)-1 react with acryloyl chloride (2) to give 1-acryloylproline esters (S)-3 in good yields. Addition of benzenesulfenyl chloride (6) to (S)-3 at -95°C in dichloromethane results in 1-[2-chloro-3-(phenylthio)propionyl]proline esters (2S,2′R/2S,2′S)-7. The diastereoselectivity of the addition depends on the conformer ratio 3′/3″ of the starting material (S)-3. The diastereomers are separated by MPLC. Configuration at C-2′ of the resulting main products (2S,2′S)-7 was proved by independent synthesis. The diastereoselectivity of the addition of 6 to (S)-3 is interpreted to result from formation of a complex of the benzenesulfenyl cation with the proline ester group and subsequent electrophilic addition to a thiiranium intermediate B with (2S,2′R) configuration; the (2S,2′S) diastereomeric adduct 7 then results by nucleophilic attack of chloride at C-2′ under ring opening.
    Notes: Die 1-Acryloylprolinester (S)-3 werden durch N-Acylierung der Prolinester (S)-1 mit Acryloylchlorid (2) in guten Ausbeuten hergestellt; sie addieren Benzolsulfenylchlorid (6) bei -95°C in Dichlormethan mit hoher Diastereoselektivität zu 1-[2-Chlor-3-(phenylthio)propionyl]prolinestern (2S,2′R/2S,2′S)-7, die mittels MPLC getrennt werden. Die Diastereoselektivität der Addition hängt vom Konformerenverhältnis 3′/3″ der Edukte (S)-3 ab. Der Beweis der Konfiguration an C-2′ der als Hauptprodukte anfallenden Diastereomeren (2S,2′S)-7 wird durch eine unabhängige Synthese erbracht. Die Diastereoselektivität der Addition von 6 an (S)-3 wird über eine Komplexbildung des Phenylsulfenylkations mit der Prolinestergruppe und eine sich anschließende elektrophile Reaktion zu einer Thiiranium-Zwischenstufe B mit (2S,2-R)-Konfiguration gedeutet; das (2S,2′S)-diastereomere Additionsprodukt 7 entsteht dann durch nucleophilen Angriff des Chlorids an C-2′ unter Ringöffnung.
    Additional Material: 7 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220324
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 65
    Electronic Resource
    Electronic Resource
    Synthesis and Structure of W2Cl4{μ-(iPr2PCH2CH2CH2PiPr2)}2: A Tungsten - Tungsten Quadruple Bond Bridged by Bulky Chelating Diphosphines (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 851-855 
    Details
    ISSN: 0009-2940
    Keywords: Diphosphines ; Tungsten - tungsten quadruple bond ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese und Struktur von W2Cl4{μ(iPr2PCH2CH2CH2PiPr2)}2: Eine durch sperrige, chelatisierende Diphosphane überbrückte Wolfram - Wolfram-VierfachbindungDie Reduktion von WCl4 in THF durch zwei Äquivalente Na/Hg in Gegenwart des sperrigen, chelatisierenden Diphosphinopropans iPr2PCH2CH2CH2PiPr2 (dippp) liefert den violetten, zweikernigen Komplex W2Cl4(μ-dippp)2. Der Komplex besitzt eine W-W-Vierfachbindung und β-Struktur, d.h. die chelatisierenden Diphosphinopropan-Liganden verbrücken die beiden Metall-Zentren. Die 1H-NMR-spektroskopischen Daten zeigen Tieffeldverschiebungen für die dippp-Liganden, die im Einklang mit der β-Struktur stehen. Das 31P{1H}-NMR-Spektrum besteht aus einem Singulett mit 183W-Satelliten. Die Röntgen-Stukturanalyse ergibt für die β-Struktur einen Torsionswinkel P-W-W-P von 75.9° und eine W-W-Bindungslänge von 2.297(1) Å. Aus den Molekülstruktur-Daten und den 1H-NMR-Tieffeldverschiebungen kann die diamagnetische Anisotropie χ der W-W-Vierfachbindung mit - 3000 ± 300 × 10-36 m3/Molekül abgeschätzt werden. Die für den festen Zustand beobachtete Chiralität wird auch in Lösung beibehalten.
    Notes: The reduction of WCl4 in THF by two equivalents of Na/Hg in the presence of the bulky chelating diphosphine iPr2PCH2-CH2CH2PiPr2 (dippp) generates the purple, binuclear complex W2Cl4(μ-dippp)2. The quadruply-bonded molecule has a β structure, that is, the chelating diphosphine bridges the two metal centers. 1H-NMR spectral data show downfield shifts for the ligand protons consistent with the β structure. The 31P{1H}-NMR spectrum consists of a singlet with 183W satellites. The X-ray crystal structure has a twist angle (P-W-W-P torsion angle) of 75.9°, and the W-W bond length is 2.297(1) Å. Using the solidstate data and the observed downfield shifts in the 1H-NMR spectrum, the diamagnetic anisotropy χ has been estimated as - 3000 ± 300 × 10-36 m3/molecule. The chiral structure observed in the solid phase is retained in solution.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220509
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 66
    Electronic Resource
    Electronic Resource
    Synthese und Charakterisierung von 1,3,2λ5,4-Thiazaphosphaboretidinen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 861-864 
    Details
    ISSN: 0009-2940
    Keywords: Aminoiminophosphanes ; 1,3,2λ5,4-Thiazaphosphaboretidines ; 1,2,4,3,5-Trithiadiborolanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Characterization of 1, 3, 2λ5, 4-ThiazaphosphaboretidinesThe reaction of 1,2,4,3,5-trithiadiborolanes with silylated aminoiminophosphanes leads to the 1,3,2λ5,4-thiazaphosphaboretidines 1a-i. The formation of 1h, i is accompanied by an exchange of the substituents bonded to the N atoms. 1H-, 11B-, 13C-, 29Si-, 31P-NMR, and mass spectra are discussed.
    Notes: Die Umsetzung von 1,2,4,3,5-Trithiadiborolanen mit silylierten Aminoiminophosphanen führt zu den 1,3,2λ5,4-Thiazaphosphaboretidinen 1a-i. Die Bildung von 1h, i wird von einem Austausch der N-ständigen Substituenten begleitet. 1H-, 11B-, 13C-, 29Si-, 31P-NMR- und Massenspektren werden diskutiert.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220511
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 67
    Electronic Resource
    Electronic Resource
    Ein bequemer Weg von Alkenylboranen zu Alkenylstannanen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 857-860 
    Details
    ISSN: 0009-2940
    Keywords: Alkenylboranes ; Alkenylstannanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Convenient Route from Alkenylboranes to AlkenylstannanesAlkenyldialkylboranes 1 with various substituents at the C=C double bond, including organometallic groups such as the trimethylstannyl or trimethylsilyl group, react in hexane solution with (diethylamino)- or (dimethylamino)trimethylstannane (2) in the presence of a catalytic amount of lithium dimethyl- or diethylamide (3) to give aminodialkylboranes 4 and alkenyltrimethylstannanes 5 in high yields with retention of the configuration at the C—C double bond. With (diethylamino)trimethylplumbane (2c) the less stable alkenes 5Pb are obtained. A mechanism is proposed, and 1H-, 13C-, 29Si-, 119Sn- und 207Pb-NMR-data are reported.
    Notes: Alkenyldialkylborane 1 mit verschiedenen Substituenten an der C=C-Doppelbindung, einschließlich organometallischer Gruppen wie dem Trimethylstannyl- oder dem Trimethylsilyl-Rest, reagieren in Hexan mit (Diethylamino)- oder (Dimethylamino)trimethylstannan (2) in Gegenwart einer katalytischen Menge von Lithium-diethylamid (3b) oder -dimethylamid (3a) in hoher Ausbeute unter Beibehaltung der Konfiguration an der C—C-Doppelbindung zu den entsprechenden Alkenylstannanen 5 und Aminoboranen 4. Durch Einsatz von (Diethylamino)trimethylplumban (2c) lassen sich die weniger stabilen Alkene 5Pb erhalten. Ein Mechanismus wird vorgeschlagen, und 1H-, 13C-, 29Si-, 119Sn- und 207Pb-NMR-Daten werden mitgeteilt.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220510
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 68
    Electronic Resource
    Electronic Resource
    Wasserstoffübertragungen, 12: Ziegler-Nickel-Katalysatoren für den Wasserstoff-Transfer (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1919-1924 
    Details
    ISSN: 0009-2940
    Keywords: Hydrogen transfer ; Ziegler catalysis ; Dihydroarenes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ziegler Nickel Catalysts for Hydrogen Transfer ReactionsCatalysts prepared from Ni(acac)2 and AlEt3 show high catalytic activity in the hydrogen transfer between dihydroarenes, but hardly any isomerisation and H/D scrambling is observed. The active form of the catalyst is produced only in the presence of the starting material. Kinetic experiments, especially those concerning the introduction periods and the inhibition, are indicative of a complex reaction mechanism. The first hydrogen is preferentially abstracted from the 2-position, the second with complete cis selectivity.
    Notes: Der aus Ni(acac)2 und AlEt3 dargestellte Katalysator zeigt eine hohe Aktivität beim H-Transfer zwischen Dihydroarenen, neben dem Isomerisierungen und H/D-Austausch kaum ablaufen. Die aktive Form entsteht erst in Gegenwart des Edukts. Kinetische Untersuchungen, vor allem zur Induktionsperiode und zur Hemmung, deuten auf einen komplexen Ablauf. Der Wasserstoff wird cis-selektiv abgespalten, primär bevorzugt aus der 2-Position.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 69
    Electronic Resource
    Electronic Resource
    Wasserstoffübertragungen, 13: (Distickstoff)hydridotris(triphenylphosphan)cobalt(I) als Disproportionierungs-Katalysator (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1925-1927 
    Details
    ISSN: 0009-2940
    Keywords: Hydrogen transfer ; Olefin isomerization ; Cobalt complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydrogen Transfer Reactions, 13.  -  Catalysis of Disproportionation by (Dinitrogen)hydridotris(triphenylphosphine)cobalt(I)For both C—H activation and olefin isomerization, CoH(N2)(PPh3)3 (1) is a more powerful catalyst than the Wilkinson complex. In 1,2-dihydronaphthalene (2), a two-step cis abstraction of the hydrogen atoms is found with small regioselectivity in the first step.
    Notes: Die Aktivität des Komplexes CoH(N2)(PPh3)3 (1) liegt bei der C—H-Aktivierung deutlich höher als beim Wilkinson-Katalysator. Noch effektiver wird aber eine Olefin-Isomerisierung induziert. Die zweistufige H-Abstraktion erfolgt beim 1,2-Dihydronaphthalin (2) cis-selektiv, der Primärschritt aber kaum regioselektiv.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221016
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 70
    Electronic Resource
    Electronic Resource
    Synthesis and ring transformation of a new fused as-triazinium salt (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1935-1938 
    Details
    ISSN: 0009-2940
    Keywords: as-Triazinium salt, fused ; Ring transformation ; Solvatochromy, negative ; Zwitterion ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese und Ringtransformation von neuen kondensierten as-Triazinium-SalzenDie Reaktion des 1,2-Diaminopyridinium-Salzes 1 mit dem Furandion 2 ergab ein Pyrido-as-triazinon 3, das zum tricyclischen Furo[2,3-e]pyrido[1,2-b]-as-triazinium-Salz 5 cyclisiert wurde. Die Reaktion von 5 mit Nucleophilen führte zu unterschiedlichen Produkten: mit wäßriger Base entstand das bicyclische Triazinon 4, mit dem Methoxid-Ion und sekundären Aminen wurden die stabilen Zwitter-Ionen 7a, b erhalten, wohingegen Ammoniak und Hydrazine unter Transformation des Furanringes die neuen tricyclischen kondensierten Pyrrole 10, 11 bzw. Pyridazine 13, 14a, b ergaben.
    Notes: The 1,2-Diaminopyridinium salt 1 was treated with furandione 2 to give pyrido-as-triazinone 3, which could be cyclized to the tricyclic furo[2,3-e]pyrido[1,2,-b]-as-triazinium salt 5. Reaction of 5 with nucleophiles resulted in different types of products. Thus, aqueous base afforded bicyclic triazinone 4, methoxide ion or secondary amine led to stable zwitterions 7a, b, whereas ammonia and hydrazines resulted in ring transformation of the furan moiety, and gave new fused tricyclic pyrroles (10, 11) and pyridazines (13, 14), respectively.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221018
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 71
    Electronic Resource
    Electronic Resource
    Enolether, XIX: Untersuchungen zur Autoxidation und zur Umlagerung von [n] (2,4) Phloroglucinophanen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1947-1953 
    Details
    ISSN: 0009-2940
    Keywords: Enol ethers ; [n](2,4)Phloroglucinophanes ; Autoxidation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigations of the Autoxidation and the Rearrangement of [n](2,4)PhloroglucinophanesIn the autoxidation of [n](2,4)phloroglucinophanes 3 hydroperoxides 7 are isolated in several cases as the first oxidation products; they react to the more stable monohydroxylated compounds 8 with different rates. Acylphloroglucinophanes 5, however, react with oxygen to give the dihydroxylated compounds 9. The autoxidation rate of the phloroglucinophanes 3, 5 is markedly larger than that of diethylphloroglucinols 6. In alkaline solution the hydroxy compounds 8 rearrange to the dihydroxycyclopentenones 12; the rate of rearrangement correlates with the decrease of ring strain.
    Notes: Bei der Autoxidation von [n](2,4)Pholoroglucinophanen 3 können in einigen Fällen Hydroperoxide 7 als erste Oxidationsprodukte isoliert werden, die unterschiedlich rasch in die stabileren monohydroxylierten Verbindungen 8 übergehen. Aclphloroglucinophane 5 reagieren mit Luftsauerstoff dagegen zu den zweifach hydroxylierten Verbindungen 9. Die Geschwindigkeit der Autoxidation ist bei den Phloroglucinophanen 3, 5 deutlich größer als bei den 2,4-Diethylphloroglucinen 6. Im alkalischen Medium lagern sich die Hydroxyverbindungen 8 in die Dihydroxycyclopentenone 12 um, wobei für die Geschwindigkeit der Umlagerung eine Korrelation mit der Abnahme an Ringspannung gefunden wird.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221020
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 72
    Electronic Resource
    Electronic Resource
    Reaktionen ungesättigter Azide, 7: Basenkatalysierte Bildung von Allenylaziden aus Propargylaziden: Neue Synthesen für 1,2,3-Triazole (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1963-1967 
    Details
    ISSN: 0009-2940
    Keywords: Allenyl azides, ring closure of ; Propargyl azides, rearrangement, base-induced ; Triazafulvenes, nucleophilic addition to ; 1,2,3-Triazoles, preparation of ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Unsaturated Azides, 7.  -  Base-catalyzed Formation of Allenyl Azides from Propargyl Azides: New Syntheses for 1,2,3-TriazolesThe propargyl azides 10, 14, 17, 20, and 28 undergo a base-catalyzed (prototropic) rearrangement to short-lived allenyl azides. These intermediates rapidly cyclize to triazafulvenes, which can be trapped by nucleophiles (methanol, sodium hydroxide, ammonia) to give 1,2,3-triazoles. Starting with the precursors 9, 13, 16, 19, and 27 one-pot syntheses lead to the heterocycles 12, 15, 18, 21, and 29. Depending on the reaction conditions, compound 10 regioselectively yields 12c (75%) by prototropic rearrangement (path B) or by migration of the azide group (path A) the isomer 11c (62%).
    Notes: Die Propargylazide 10, 14, 17, 20 und 28 lagern sich basenkatalysiert (prototrop) zu kurzlebigen Allenylaziden um. Diese Zwischenstufen cyclisieren rasch zu Triazafulvenen, die mit Nucleophilen (Methanol, Natriumhydroxid, Ammoniak) als 1,2,3-Triazole abgefangen werden können. Ausgehend von den Vorläufern 9, 13, 16, 19 und 27 führen Eintopf-Synthesen zu den Heterocyclen 12, 15, 18, 21 und 29. In Abhängigkeit von den Reaktionsbedingungen liefert 10 über die prototrope Umlagerung (Weg B) regioselektiv 12c (75%) oder durch Azidwanderung (Weg A) die isomere Verbindung 11c (62%).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221022
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 73
    Electronic Resource
    Electronic Resource
    Reductive lithiation of sulfides and sulfones  -  A novel entry into [2,3] wittig rearrangements (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2023-2025 
    Details
    ISSN: 0009-2940
    Keywords: Homoallylic alcohols ; [2,3] Sigmatropic rearrangement ; Stereoselective synthesis of alcohols ; [2,3] Wittig rearrangement ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reductive cleavages of allyl [(phenylthio)methyl] ethers (8, 11) and an allyl [(tolylsulfonyl)methyl] ether (14) with lithium naphthalenide in THF furnish homoallylic alcohols (9, 12). The steric course of these transformations (E/Z selectivity in the case of 9, syn/anti selectivity for 12) is very similar to that of analogous Wittig-Still rearrangements.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221033
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 74
    Electronic Resource
    Electronic Resource
    Addition von metalloganischen Nucleophilen an Koordinierte 1,3-Diene, Trimethylenmethan und Cycloheptatrienyl: Heterobimetallische carbonyl Molybdän-Rhenium-Komplexe mit σ,π-C4- und-C7-Kohlenwasserstoffbrücken (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2031-2031 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221035
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 75
    Electronic Resource
    Electronic Resource
    Pentaphosphaferrocene als Komplexliganden (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2049-2054 
    Details
    ISSN: 0009-2940
    Keywords: Ligating properties ; Pentaphosphaferrocenes ; Sandwich and triple-decker complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Pentaphospaferrocenes as Complex LigandsThe interaction of [Cp*Fe(P5)] (1a) with [Cr(CO)5(thf)] and [Cp(CO)2Mn(thf)], respectively, affords [Cp*Fe(P5){Cr(CO)5}2] (2) as well as [Cp*Fe(P5){Mn(CO)2Cp}n] (4a-d; n = 1-4; Cp* = η5-C5Me5). Irradiation of 1 and [CpFe(C6H6)]PF6 gives the cationic 30-VE triple-decker complexes [CpFe(μ, η5-P5)Fe(C5Me4R)]PF6 (3a: R = CH3; 3b: R = C2H5; Cp = η5-C5H5). In addition to the NMR studies 2 and 3b have been characterized by X-ray structure analyses.
    Notes: Die Umsetzung von [Cp*Fe(P5)] (1a) mit [Cr(CO)5(THF)] bzw. [Cp(CO)2Mn(THF)] ergibt [Cp*Fe(P5){Cr(CO)5}2] (2) sowie [HCp*Fe(P5){Mn(CO)2Cp}n] (4a-d; 1-4; Cp* = η5-C5Me5). Aus 1 und [CpFe(C6H6)]PF6 lassen sich photochemisch die kationischen 30-VE-Tripeldeckerkomplexe [CpFe(μ, η5-P5)Fe(C5Me4R)]PF6 (3a: R = CH3; 3b: R = C2H5; Cp = η5-C5H5) aufbauen. Zusätzlich zu den NMR-spektroskopischen Studien wurden von 2 und 3b Kristallstrukturanalysen angefertigt.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221104
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 76
    Electronic Resource
    Electronic Resource
    Masthead (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221101
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 77
    Electronic Resource
    Electronic Resource
    Organische Synthesen mit Übergangsmetallkomplexen, 35. (C-Amino)ketenimine, 2-Imidazolin-5-one und α-Aminosäureamide aus (Aminocarben)chromkomplexen und Isocyaniden (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1139-1145 
    Details
    ISSN: 0009-2940
    Keywords: C-(Alkylideneamino)ketene imines ; Isocyanides, C=C coupling with aminocarbene ligands ; (2-Azaallenyl)chromium complexes ; 2-Imidazolin-5-ones ; α-Amino acids ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organic Syntheses via Transition Metal Complexes, 35. - (C-Amino) Ketene Imines, 2-Imidazolin-5-ones, and α-Amino Acids from Aminocarbene Chromium Complexes and IsocyanidesC-(Alkylidenamino)ketene imines 1,4-diaza-1,2,4-pentatrienes) 8 are easily accessible by C=C coupling of isocyanides R1 - NC (2, R1 = t-C4H9, c-C5H11, CH3) with the (alkylideneamino)carbene (= 2-azaallenyl-) ligand of (6). The tendency for an insertion of 2 into M=C bonds of aminocarbene complexes strongly depends on the electronic character of the aminocarbene ligand. Electron-rich aminocarbene chromium complexes like (CO)5Cr=C(NR2)C6H5 (1, R = H, CH3), show only little tendency for an insertion but mainly give cis-(R1-NC)(CO)4Cr=C(NR2C6H5 (3) by substitution of CO. Electron-poor aminocarbene complexes like 6 (readily available on N-benzoylation of 1a) undergo a facile insertion of 2 into the M=C bond with smooth formation of 7. From 7 ketene imine 8 is spontaneously disengaged by a second equivalent of 2. The reaction works especially well with bulky isocyanides 2a, b. In the case of methyl isocyanide (2c) a [bis(imino)dihydropyrrol]chromium complex 15 is obtained as a minor product besides 8c. 15 results from a [4+1] cycloaddition of 2c at the ketene imine ligand of 7c. C-(Alkylideneamino)ketene imines 8 are easily accessible by our method. They prove to be very thermolabile in solution and spontaneously isomerize to give 2-imidazolin-5-ones 10 and C-amidoketene imines 11. Under the influence of wet silica gel keten imine derivatives 8 rapidly form α-amino acid amides 16 by hydrolysis with concomitant migration of a benzoyl group. Under the same conditions 11 also gives the „normal“ α-amino acid amides 17.
    Notes: C-(Alkylideneamino)ketenimine (1,4-Diaza-1,2,4-pentatriene) 8 wurden durch C=C-Kupplung von Isocyaniden R1-NC (2, R1 = t-C4H9, c-C5H11, CH3) mit dem (Alkylideneamino)carben-(= 2-Azaallenyl-)Ligand von (6) erstmals hergestellt. Die Bereitschaft zur Insertion von 2 in M=C-Bindungen von Aminocarbenkomplexen hängt stark von den elektronischen Eigenschaften der Aminocarbenliganden ab. Elektronenreiche (Aminocarben)chromkomplexe, wie z. B. (CO)5Cr=C(NR2)C6H5 (1, R = H, CH3), zeigen eine nur geringe Neigung zur Insertion von 2 und bilden bevorzugt cis-(R1-NC)(CO)4Cr=C(NR2C6H5 (3) unter Substitution von CO. Elektronenarme (Aminocarben)chromkomplexe hingegen, wie z. B. 6 (durch N-Benzoylierung von 1a leicht zugänglich), zeigen ausschließlich Insertion zu 7. Aus 7 wird spontan 8 freigesetzt durch Substitution mit einem zweiten Äquivalent 2. Sperrige Isocyanide 2a, c reagieren besonders einheitlich. Mit Methylisocyanid (2c) entsteht zusätzlich zu 8c der [Bis(imino)dihydropyrrol]-chromkomplex 15 unter [4+1]-Cycloaddition von 2c am Keteniminligand von 7c. C-(Alkylidenamino)ketenimine 8 sind nach unserem Verfahren einfach zugänglich; sie isomerisieren jedoch leicht zu 2-Imidazolin-5-onen 10 und C-Amidoketeniminen 11. An feuchtem Kieselgel entstehen aus 8 rasch α-Aminosäureamide 16 durch Hydrolyse unter Wanderung eines Benzoylrestes; aus 11 unter gleichen Bedingungen zusätzlich „normale“ α-Aminosäureamide 17.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220620
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 78
    Electronic Resource
    Electronic Resource
    Donorsubstituierte Benzonitrile als Seitenkettendienophile bei der intramolekularen [4 + 2]-Cycloaddition mit inversem Elektronenbedarf (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2177-2181 
    Details
    ISSN: 0009-2940
    Keywords: Benzonitriles ; Hetero Diels-Alder reactions, “inverse” ; Pyrazines, annulated ; Triazines, benzofuro- and benzothieno- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Donor-Substituted Benzoitriles as Side-Chain Dienophiles in the Intramolecular [4+2] Cycloaddition with Inverse Electron DemandExpanding the scope of the intramolecular Diels-Alder reaction of 1,2,4,5-tetrazines to include donor-substituted benzonitriles as side-chain dienophiles we describe synthetic routes to novel fused heterotricycles such as the benzofuro[3,2-e]-1,2,4-triazines 11a, b and the benzothieno[3,2-e]-1,2,4-triazines 14a, b, and 17. The doubly annulated pyrazines 22 and 23 are constructed by a subsequent second intramolecular Diels-Alder cycloaddition of the benzonitrile moiety with the fused 1,2,4-triazine system, starting from 11a and 14a.
    Notes: Unter Einschluß donorsubstituierter Benzonitrile als Seitenkettendienophile haben wir die Anwendungsbreite der intramolekularen Diels-Alder-Reaktion von 1,2,4,5-Tetrazinen erweitert und beschreiben Synthesewege zu neuen anellierten Heterotricyclen wie den Benzofuro[3,2-e]-1,2,4-triazinen 11a, b und den Benzothieno[3,2-e]-1,2,4-triazinen 14a, b sowie 17. Die doppelt anellierten Pyrazine 22 und 23 lassen sich durch eine nachfolgende zweite intramolekulare Benzonitril/1,2,4-Triazin-Diels-Alder-Cycloaddition mit 11a bzw. 14a als Edukten herstellen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221119
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 79
    Electronic Resource
    Electronic Resource
    Intramolekulare Cycloadditionen mit Nitriloxiden: Untersuchungen zur Synthese von Heterophanen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2147-2157 
    Details
    ISSN: 0009-2940
    Keywords: 1,3-Dipolar cycloadditions, intramolecular ; Nitrile oxides ; Regioselectivity ; Furanophanes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramolecular Cycloadditions with Nitrile Oxides: Investigtions towards the Synthesis of HeterophanesThe intramolecular cycloaddition reactions of the nitrile oxides 30a-d, 35, 36, and 47, obtained in situ from the 2,5-difunctional furan hydroximoyl chlorides 12a, b, 18 and the nitro compounds 9c, d, 21, 29, are described. With 30c the expected isoxazolofuranophane of type 31 is formed in acceptable yield; the additionally formed regioisomer 32c and the dimer 34c are very minor products in this case. Whereas the highest homologue 30d gives a complex product mixture with small amounts of 31 d and the macrocycle 34d as the only identified compounds, the derivatives bearing a shorter side chain (30a, b; n = 1, 2) give rise to the exclusive reaction of the dipole with a double bond of the furan system (to give 33a, b). The same behavior is observed in the case of the electronically and sterically modified dipole systems 35/36 and 47, resp.; in spite of the much more favorable conditions for the formation of cyclophanes the cycloadditions result in the exclusive formation of the heterotricycles 41, 42 and 49. Possible preparative applications of the isomeric cycloaddition compounds are discussed.
    Notes: Die intramolekularen Cycloadditionsreaktionen der aus 2,5-difunktionellen Furan-Hydroximsäurechloriden (12a, b und 18) bzw. den Nitroverbindungen 9c, d, 21 und 29 in situ hergestellten Nitriloxide 30a-d, 35, 36 und 47 werden beschrieben. Eine Reaktion zu den angestrebten Isoxazolo-furanophanen des Typs 31 verläuft für 30c in brauchbarer Ausbeute; das Regioisomere 32c sowie das Dimere 34c treten hierbei nur in geringem Maße auf. Während das höchste Homologe 30d neben 31d und dem Makrocyclus 34d hauptsächlich Zersetzungsprodukte bildet, reagieren die Derivate mit kürzerer Seitenkette (30a, b; n = 1, 2) ausschließlich unter dipolarer Addition an eine Furandoppelbindung zu 33a, b. Für n = 1 entsprechen diesem Verhalten auch die elektronisch bzw. sterisch modifizierten Dipolsysteme 35/36 und 47, die trotz günstigerer Voraussetzungen für die Cyclophanbildung nur zu den Tricyclen 41, 42 bzw. 49 reagieren. Die präparativen Anwendungsmöglichkeiten der isomeren Cycloadditionsverbindungen als Synthesezwischenprodukte werden diskutiert.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221116
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 80
    Electronic Resource
    Electronic Resource
    Synthesis of 3,5-dihydroxytropone (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2183-2185 
    Details
    ISSN: 0009-2940
    Keywords: [4 + 2] Cycloaddition ; 3,5-Dihydroxytropone ; Singlet oxygen ; Y aromaticity ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese von 3,5-DihydroxytroponWir beschreiben eine vierstufige Synthese des bisher unbekannten 3,5-Dihydroxytropons (6), die von Tropon ausgeht und eine [4 + 2]-Cycloaddition mit Singulett-Sauerstoff einschließt.
    Notes: Starting from tropone, the hitherto unknown 3,5-dihydroxytropone (6) is prepared in a four-step synthesis including a [4 + 2] cycloaddition reaction of singlet oxygen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221120
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 81
    Electronic Resource
    Electronic Resource
    Hetero diels-alder reactions of allenes on silica gel surface and under liquid-phase conditions (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2207-2208 
    Details
    ISSN: 0009-2940
    Keywords: Allenes ; Hetero Diels-Alder reactions ; Catalysis, heterogeneous ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some examples of cycloadditions of 1-ethoxy-1,2-propadiene with 1-oxa-1,3-dienes, catalyzed by acid-free silica gel, are reported.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221124
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 82
    Electronic Resource
    Electronic Resource
    Masthead (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989) 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 83
    Electronic Resource
    Electronic Resource
    Metal complexes with tetrapyrrole ligands, LIV: Synthesis, spectra, structure, and redox properties of cerium(IV) Bisporphyrinates with identical and different porphyrin rings in the sandwich system (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2219-2228 
    Details
    ISSN: 0009-2940
    Keywords: Bisporphyrinates, cerium(IV) ; Lanthanoid porphyrins ; Metalloporphyrins ; Tetrapyrrole complexes, sandwich-like ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metallkomplexe mit Tetrapyrrol-Liganden, LIV.  -  Synthese, Spektren, Struktur und Redox-Chemie von Cer(VI)-Bisporphyrinaten mit gleichen und verschiedenen Porphyrin-Ringen im Sandwich-SystemWeitere symmetrische Cer(IV)-Bisporphyrinate werden aus Cer-(III)-acetylacetonat und Tetraphenylporphyrin, Tetra-p-chlorphenylporphyrin, und Hexadecahydrotetrabenzporphyrin hergestellt. Aus dem letzteren Porphyrin entsteht auch ein Biscer(III)-Tripeldecker; ein solcher bildet sich als einziges Produkt aus Octamethylporphyrin. Aus einem Gemisch zweier verschiedener Porphyrine, nämlich Octaethylporphyrin [H2(OEP)], und Tetraphenyl-porphyrin [H2(TPP)] oder Tetra-p-chlorphenylporphyrin [H2-(TClP)] erhält man neben den symmetrischen Spezies Ce(OEP)2 und Ce(TPP)2 die unsymmetrischen („gemischten“) Doppeldecker Ce(OEP)(TPP) oder Ce(OEP)(TClP), die verschiedene Porphyrin-Ringe im Sandwich-System haben und sich trennen lassen. Die Kristallstrukturanalyse von Ce(OEP)(TPP) zeigt CeIV in quadratisch-antiprismatischer Umgebung der Pyrrol-N-Atome der Porphyrin-Ringe. Während die IR- und NMR-Spektren der unsymmetrischen Doppeldecker-Überlagerungen der Spektren, die einzelnen Ringe darstellen, zeigen ihre UV/VIS-Spektren und die cyclischen Voltammogramme, daß die zwei unterschiedlichen Porphyrin-Ringe sich wie ein gemeinsames π-Elektronensystem verhalten. Die Darstellung der π-Kation-Radikal-Salze [Ce(OEP)2]-ClO4 und [Ce(OEP)(TPP)]SbCl6 wird ebenfalls beschrieben. In letzterem scheint sich das Defektelektron bevorzugt im OEP-Ring aufzuhalten.
    Notes: Further symmetrical cerium(IV) bisporphyrinates are prepared from cerium(III) acetylacetonate and tetraphenylporphyrin, tetra-p-chlorophenylporphyrin, and hexadecahydrotetrabenzporphyrin. In the latter case, a biscerium(III) triple-decker is also found which is the only product in the case of octamethylporphyrin. From a mixture of two different porphyrins, namely octaethylporphyrin [H2(OEP)] and either tetraphenylporphyrin [H2(TPP)] or tetra-p-chlorophenylporphyrin [H2(TClP)], besides the symmetrical species Ce(OEP)2 and Ce(TPP)2, the unsymmetrical (“mixed”) double-deckers Ce(OEP)(TPP) or Ce(OEP)(TClP) are obtained which have different porphyrin rings in the sandwich system and can be separated by chromatography. The crystal structure analysis of Ce(OEP)(TPP) shows CeIV in a square-antiprismatic geometry of the pyrrole N atoms of the porphyrin rings. While the IR and NMR spectra of the unsymmetrical double-deckers are superpositions of the spectra of the individual rings, their UV/VIS spectra and cyclic voltammograms indicate that the two porphyrin rings behave as a common π-electron system. The preparation of the π-cation radical salts [Ce(OEP)2]ClO4 and [Ce(OEP)(TPP)]SbCl6 is also described. In the latter, the defect electron seems to reside preferentially in the OEP ring.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221203
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 84
    Electronic Resource
    Electronic Resource
    Aufbau von Fe—Sn-Bindungen über die Reaktion von Tris(trimethylstannyl)amin mit Fe(CO)5 und Fe(CO)4CS; 13C-, 17O- und 119Sn-NMR-spektroskopische Untersuchungen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2261-2264 
    Details
    ISSN: 0009-2940
    Keywords: Iron, thiocarbonyl complex ; Iron-tin bond ; NMR, 13C-, 17O-, and 119Sn ; Dynamic molecules ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Formation of Fe-Sn Bonds by the Reaction of Tris(trimethylstannyl)amine with Fe(CO)5 and Fe(CO)4CS; 13C-, 17O-, and 119Sn-NMR-Spectroscopic StudiesThe reaction between N(SnMe3)3 and Fe(CO)5 gives the known complex cis-Fe(CO)4(SnMe3)2 (1) in high yield. In the analogous reaction of Fe(CO)4CS the complex fac-Fe(CO)3(CS)(SnMe3)2 (2) is obtained together with small amounts of 1. In addition to the 13C-NMR data, the 17O- and 119Sn-NMR measurements proved particularly useful for studying the dynamic behaviour of 1 and 2.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 85
    Electronic Resource
    Electronic Resource
    Dichlorobis(η5-cyclopentadienyl)rhenium(VII)-tris(hexafluoroantimonat): Synthese des ersten Rhenocen(VII)-dichlorid-Kations (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2273-2274 
    Details
    ISSN: 0009-2940
    Keywords: Fluorine, application in organometallic chemistry ; Rhenocene(V)-trichloride ; Rhenocene(VII)-dichloride trication ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dichlorobis(η5-cyclopentadienyl)rhenium(VII) Tris(hexafluoroantimonate): Synthesis of the First Rhenocene(VII) Dichloride CationRhenocene trichloride ([Cp2ReCl2]⊕ Cl⊖, 1) reacts with one equivalent of AgSbF6 and three equivalents of SbF5 to provide [Cp2ReCl2]3⊕[SbF6]⊖3 (2) in high yield. 2 contains the first rhenocene(VII) dichloride cation and is the first member of a 16-electron group-7 species of the type [Cp2MCl2]n⊕ [EF6]n⊖ (M = Ti, Zr, Hf: n = 0; M = V, Nb: n = 1; M = Mo, W: n = 2; M = Re: n = 3; E = As, Sb).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221211
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 86
    Electronic Resource
    Electronic Resource
    Darstellung und Eigenschaften von und Reaktionen mit metallhaltigen Heterocyclen, LXVII: Stereochemische Einflüsse auf den Übergang von monomeren Thiophosphinitomangan-Verbindungen zu den dimeren Komplexen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2269-2271 
    Details
    ISSN: 0009-2940
    Keywords: Manganese complexes ; Thiophosphinito complexes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Metal-Containing Heterocycles: Preparation, Properties, Reactions, LXVII.  -  Stereochemical Impacts on the Transition of Monomeric Thiophosphinito Manganese Compounds to the Dimeric Complexes The η2-thiophosphinito manganese complexes (3d, e) and the dimeric complexes (4a-c, f) are obtained from BrMn(CO)5 (1) and the secondary phosphane sulfides R2P(S)H (2a-f) [R = Me (a), Et (b), n-Pr (c), i-Pr (d), Cy (e), Ph (f)] in the presence of the auxiliary base Et(i-Pr)2N with elimination of CO. For the kinetic stabilization of 3d, e sterically demanding substituents R at the phosphorus are suitable. The Mn—S bond in 3e is easily cleaved under CO pressure (100 bar) resulting in the formation of (5e). The reaction 3e ⇆ 5e is reversible.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 87
    Electronic Resource
    Electronic Resource
    Synthese und Eigenschaften von iPr2InCl, iPrInCl2 und (iPr2InNHtBu)2 (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2283-2287 
    Details
    ISSN: 0009-2940
    Keywords: Indium, trialkyl derivatives ; Dialkylchloroindium ; Alkyldichloroindium ; Alkylindium dialkylamides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Properties of iPr2InCl, iPrInCl2, and (iPr2InHRtBu)2The reactions of triisopropylindium (1) with half an equivalent or two equivalents of indium (III) chloride leads to iPr2InCl (2) and iPrInCl2 (3), respectively. (iPr2InNHtBu)2 (4) can be synthesized from 2 and LiNHtBu. According to NMR, IR, and RE studies, 2-4 from dimers in solution and solid state. The X-ray analysis of 4 is reported.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221214
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 88
    Electronic Resource
    Electronic Resource
    Propiniminium-Salze: Ambifunktionelle Reaktivität gegenüber S- und N-Nucleophilen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2311-2317 
    Details
    ISSN: 0009-2940
    Keywords: Allenes, 1,3-diamino- and 1-amino-3-thio- ; Propene iminium salts ; Propyne iminium salts ; MO calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Propyne Iminium Salts: Ambifunctional reactivity reactivity towards Sulfur and Nitrogen NucleophilesPropyne iminium ions 2a-d have been studied by both ab initio (3-21G//3-21G for 2a) and MNDO calculations (2a-d). It is found that the amino group stabilizes the propargyl cation structure at the expense of the allenyl cation structure. Furthermore, the highest positive charge density is located at the amino-substituted carbon atom.  -  Reactions of 2-propyne iminium triflates 6a, b with thiols, thiolates, morpholine, lithium morpholide, and phenylhydrazine have been investigated. C-1 attack at 6, expected under kinetically controlled conditions, is observed in a few cases only. In all other cases, products resulting from C-3 attack takes place leading either to 1,3-donorsubstituted allenes (8, 10, 12) in the absence of proton sources or to their C-2-protonated forms (9, 11, 13-15) otherwise.
    Notes: Für die Propiniminium-Ionen 2a-d werden ab-initio- (3-21G//3-21G für 2a) und MNDO-Rechnungen (2a-d) durchgeführt. Danach stabilisiert die Aminogruppe die Propargylkation- eindeutig gegenüber der Allenylkation-Struktur. Die höchste positive Ladungsdichte befindet sich am aminosubstituierten Kohlenstoffatom.  -  Umsetzungen der 2-Propiniminium-triflate 6a, b mit Thiolen, Thiolaten, Morpholin, Lithium-morpholid und Phenylhydrazin zeigen, daß nur in einigen Fällen unter kinetisch kontrollierten Bedingungen der erwartete C-1-Angriff erfolgt, ansonsten wird C-3-Angriff gefunden. Letzterer führt in Abwesenheit von Protonquellen zu 1,3-donorsubstituierten Allenen (8, 10, 12), andernfalls entstehen deren C-2-protonierte Formen (9, 11, 13-15).
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221218
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 89
    Electronic Resource
    Electronic Resource
    Cycloadditionen, 17: Einfluß von Methyl- und Phenylgruppen in der allenischen ω-Position auf die thermisch induzierten Isomerisierungen von N-[2-Furanyl-(Thienyl-, Pyrrolyl-)-methyl]allencarboxamiden (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2331-2339 
    Details
    ISSN: 0009-2940
    Keywords: Diels-Alder reactions, intramolecular ; Allenecarboxyamides, N-(hetarylmethyl)- ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadditons, 17.  -  Influence of Methyl and Phenyl Groups in the Allenic ω-Position on the Thermally Induced Isomerizations of N-[2-Furanyl-(Thienyl-, Pyrrolyl-)methyl] allenecaboxamindesThe N-(2-hetarylmethyl)-1,2-alkadienecarboxamides 9a-q were synthesized by the ylide route, and their readiness to participate in the intramolecular Diels-Alder reaction was studied. Whereas the pyrrole derivatives 9p and 9q and the thiophene derivative 9o without directly bonded phenyl nuclei only decompose, the thiophene allenes 9m and 9n form the “normal” tricycles 12a and 12b by reaction of their amide phenyl nucleus (R1 = Ph). In all N-furfurylallenecarboxamides 9a-1 the furan nucleus is involved in the intramolecular Diels-Alder reaction, irrespective of the amine substituent R1. The furan nucleus reacts in all cases with the terminal allenic double bond to form the oxatricycles 10a-1 containing a six-membered lactam moiety. Reaction with the first allenic double bond (formation of 11c, d, and g) only takes place, when the reaction with the other double bond is slowed down by one or two methyl groups in the ω-position and the formation of 11 is not prevented by a methyl group in the furan 5-position.
    Notes: Die N-(2-Heteroarylmethyl)-1,2-alkadiencarboxamide 9a-q werden auf dem Ylid-Weg synthetisiert und auf ihre Bereitschaft zur intramolekularen Diels-Alder-Reaktion untersucht. Die Pyrrolderivate 9p und 9q und das Thiophen-Derivat 9o ohne direkt gebundenen Phenylkern zeigen lediglich Zersetzung, während die Thiophen-Allene 9m und 9n durch Reaktion ihrer Amid-Phenylkerne (R1 = Ph) die „normalen“ Tricyclen 12a und 12b bilden. In allen Furfuryl-allencarboxamiden (9a-1) geht der Furankern die intramolekulare Diels-Alder-Reaktion ein, unabhängig von der Art des Aminsubstituenten R1. Der Furankern reagiert in allen Fällen mit der endständigen Doppelbindung zu den Oxatricyclen 10a-1 mit sechsgliedrigem Lactamteil. Reaktion mit der ersten allenischen Doppelbindung (s. Bildung von 11c,d und g) wird daneben nur beobachtet, wenn durch Einbau von Methyl-gruppen in die ω-Position die Reaktion mit der endständigen Doppelbindung stark verlangsamt und die Bildung von 11 nicht durch eine Methylgruppe in der Furan-5-Position verhindert wird.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221221
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 90
    Electronic Resource
    Electronic Resource
    Cycloadditionen an die Doppelbindung von (R)-2-tert-Butyl-Δ4-1,3-oxazolin-3-carbonsäure-methylestern (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2377-2389 
    Details
    ISSN: 0009-2940
    Keywords: EPC syntheses ; Δ4-1,3-Oxazoline, derivatives ; Simmons-Smith reaction ; Sakurai reaction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadditions to the Double Bond of Methyl (R)-2-tert-Butyl-Δs4-1,3-oxazoline-3-carboxylates1The title compounds (with or without an additional substituent, such as methyl or vinyl, in the 5-position) are allowed to react with peracids (→ dihydroxy derivatives 3), with cyclopropanation reagents (such as ICH2ZnEt, N2CHCOOEt, HCBr3, or HCCl3/NaOH → products 5-9), with tetracyanoethylene and OsO4 (see four- and five-membered rings in 19, 20), with dienophiles (maleic anhydride, see 23). The double bond of the oxazolines reacts in a highly diastereoselective manner, with the attack preferred from the face of the five-membered ring remote from the tert-butyl group. Some of the products obtained undergo or are subjected to further reactions (4, 12-18, 23, 29-33). Stereochemical and synthetic aspects of the reactions are discussed.
    Notes: Die Titelverbindungen (mit und ohne zusätzliche Substituenten wie z. B. Methyl oder Vinyl in der 5-Stellung) werden mit Persäuren (→ Dihydroxyderivate 3), mit Cyclopropanierungsreagentien (wie z.B. ICH2ZnEt, N2CHCOOEt, HCBr3 oder HCCl3/NaOH → Produkte 5-9), mit Tetracyanethylen und OsO4 (→ Produkte 19-20) und mit Dienophilen (Maleinsäureanhydrid, siehe 23) umgesetzt. Die Doppelbindung der Oxazoline reagiert hoch diastereoselektiv, wobei der bevorzugte Angriff von der der tert-Butylgruppe abgewandten Seite erfolgt. Einige der erhaltenen Produkte werden weiter umgesetzt (siehe 4, 12-18, 23, 29-33). Stereochemische und synthetische Aspekte der Reaktionen werden diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221226
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 91
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen, 52: Tryptamin-Verbindungen mit Seitenkettensubstitution aus Indolyllithium und aktivierten Aziridinen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2397-2398 
    Details
    ISSN: 0009-2940
    Keywords: Nucleophilic ring opening ; Regioselectivity ; Ambident nucleophiles ; Aziridines ; Tryptamine ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions with Aziridines, 52.  -  branched-Chain Tryptamine Compounds from Indolyllithium and Activated AziridinesReaction of indolyllithium 1 with activated aziridines 2 in toluene provides the tryptamines 3 or 4 in good yields.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221229
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 92
    Electronic Resource
    Electronic Resource
    Regioselective cycloaddition of 1,2-disubstituted aziridines to heterocumulenes catalyzed by organoantimony halides (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 2407-2409 
    Details
    ISSN: 0009-2940
    Keywords: Organoantimony halides ; Aziridines, cycloaddition of, α-cleavage of ; Heterocumulenes ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the presence of catalytic amounts of organoantimony(V) halides such as Ph4SbI, Ph4SbBr, Ph3SbBr2, and Ph3SbCl2, the cycloaddition of aziridines 1a-g with heterocumulenes (phenyl isothiocyanate, carbon disulfide, and carbon dioxide) selectively gave ring-expanded cycloadducts 3a-d, f, g, and 6e by α-cleavage of the aziridine rings.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221232
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 93
    Electronic Resource
    Electronic Resource
    Rotationsbarrieren gespannter Olefine (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1263-1275 
    Details
    ISSN: 0009-2940
    Keywords: Rotational barriers ; Olefins, strained ; Heat of hydrogenation ; Force-field calculation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Rotational Barriers of Strained OlefinesFor the olefins 1-8 heats of formation have been derived from heats of hydrogenation and force-field calculations, respectively. From the kinetics of their geometrical isomerisation the corresponding values for the transition states were obtained. The rotational barriers, which vary by nearly 30 kcal/mol, can be described by a unique torsional potential (65.9 ± 0.9 kcal/mol), which is independent of the degree of substitution, if a correction is made for the steric energy contribution in the ground- and transition-states.
    Notes: Für die Olefine 1-8 wurde durch Hydrierwärme-Messung bzw. Kraftfeld-Rechnung die Bildungsenthalpie der Grundzustände und durch kinetische Analyse der geometrischen Isomerisierung die der Übergangszustände ermittelt. Die um fast 30 kcal/mol variierenden Rotationsenthalpien lassen sich mit einer einheitlichen, vom Substitutionsgrad unabhängigen Torsionsbarriere (65.9 ± 0.9 kcal/mol) beschreiben, wenn um die sterischen Energiebeiträge der Grund- und Übergangszustand korrigiert wird.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220710
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 94
    Electronic Resource
    Electronic Resource
    [4+2]-Cycloadditionen von 2-Cyclopropyliden-1,3-dionen mit elektronenreichen Alkinen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1285-1290 
    Details
    ISSN: 0009-2940
    Keywords: 2-Cyclopropylidene-1,3-diones ; Hetero Diels-Alder reaction ; Cyclopropane derivatives ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: [4+2] Cycloaddition reactions of 2-Cyclopropylidene-1,3-diones with Electron-Rich AlkynesCyclopropylidenedimedone 3, an unstable and highly reactive intermediate, is trapped in a Hetero Diels-Alder reaction by the addition of ynamines 7a-c, f, ynether 7d, or phenylacetylene (7e). Hydrolysis of the resulting cycloadducts 8a-d, f leads to carboxylic acid derivatives 9a-d, f. The latter may be regarded as the result of a twofold nucleophilic substitution at a cyclopropane system according to their synthesis by the sequence 17 → 5 → 8 → 9. An opening of the cyclopropane ring takes place during hydrolysis of cycloadduct 8e producing 11. Analogously, 2-cyclopropylidene-1,3-diones 13A-13C can be generated by aminocyclopropylation of CH acids 18A-18C and subsequent deamination induced by an acylation reaction. Trapping of 13A-13C by ethoxyacetylene (7d) or ethyl vinyl ether (4) provides the analogous cycloadducts 14A, B and 15C.
    Notes: Cyclopropylidendimedon 3, eine unbeständige und hochreaktive Zwischenstufe, kann durch Inamine 7a-c, f, Inether 7d oder Phenylacetylen (7e) in einer Hetero-Diels-Alder-Reaktion abgefangen werden. Die resultierenden Cycloaddukte 8a-d, f sind zu Carbonsäurederivaten 9a-d, f hydrolysierbar, die entsprechend ihrer Herstellung über die Reaktionssequenz 17 → 5 → 8 → 9 als Produkte einer zweifachen nucleophilen Substitution am Cyclopropan anzusehen sind. Das Cycloaddukt 8e läßt sich dagegen nur unter Öffnung des Dreirings zu 11 hydrolysieren. Analog können die 2-Cyclopropyliden-1,3-dione 13A-13C durch Aminocyclopropylierung von CH-Säuren 18A-18C und anschließende Desaminierung erzeugt und unter Zusatz von Ethoxyacetylen (7d) oder Ethylvinylether (4) zu den Cycloaddukten 14A, 14B und 15C abgefangen werden.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220712
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 95
    Electronic Resource
    Electronic Resource
    Diels-Alder-Reaktionen mit Diakzeptor-substituierten Methylencyclopropanen  -  Ein neuer Aspekt für die doppelte nucleophile Substitution an Cyclopropanen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1277-1284 
    Details
    ISSN: 0009-2940
    Keywords: Diels-Alder reaction ; Cyclopropanes ; Dienophile reactivity ; MNDO calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Diels-Alder Reactions with Diacceptor-Substituted Methylene-cyclopropanes - A New Aspect for the Twofold Nucleophilic Substitution at Cyclopropanes(Diacylmethylene)cyclopropanes 3, generated from aminocyclopropanes 1 or 2 and acetyl chloride as highly reactive intermediates, are trapped by dienes 9a-c yielding the Diels-Alder products 10. Regioisomers 10Ab and 10Ac were isolated exclusively from the interaction of 1A with pentadiene 9b and isoprene (9c), respectively. Cycloadditions with bicyclic methylenecyclopropanes 3A and 3B stereospecifically generated the 1α,6α,7β-isomers 10A and 10B. Starting from 10 the products 16, 19, and 20 are obtained by a degradation reaction of the Meldrum's acid moiety or by an oxidative ring cleavage of the cyclohexene unit. An X-ray structural analysis is reported for 10Ac. Using MNDO calculations the reactivity of various (diacylmethylene)cyclopropanes 3 as dienophiles has been studied.
    Notes: (Diacylmethylen)cyclopropane 3, die als hochreaktive Zwischenstufen aus den Aminocyclopropanderivaten 1 bzw. 2 in Gegenwart von Acetylchlorid erzeugt werden, reagieren mit Dienen 9a-c zu Diels-Alder-Produkten 10. Aus der Umsetzung von 1A mit Pentadien 9b bzw. Isopren (9c) werden ausschließlich die Regioisomeren 10Ab und 10Ac isoliert. Die Cycloadditionen an die bicyclischen Methylencyclopropane 3A und 3B verlaufen stereospezifisch zu 1α,6α,7β-Isomeren 10A und 10B. Aus 10 lassen sich durch Abbau der Meldrumsäure bzw. durch oxidative Ringöffnung des Cyclohexens die Folgeprodukte 16,19 und 20 herstellen. Von 10Ac wurde eine Kristallstrukturanalyse angefertigt. Die Dienophil-Reaktivität von verschiedenen (Diacylmethylen)cyclopropanen 3 wird mit MNDO-Rechnungen untersucht.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220711
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 96
    Electronic Resource
    Electronic Resource
    Synthesen mit Nitrilen, LXXXII:Über Spiro[indan-pyrane] und Inden-propellane  -  Addukte von 1,3-Dicarbonylverbindungen an 2-(Dicyanmethylen)-1,3-indandion (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1323-1328 
    Details
    ISSN: 0009-2940
    Keywords: Nitriles ; Spiro compounds ; Propellanes ; Indan derivatives ; Cycloaddition ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese with Nitriles, LXXXII1). - On spiro [indan-pyrans] and Indene-propellanes - Adducts of 2-(Diccyanomethylene)-1,3-indandione with 1,3-Dicarbonyl CompoundsThe reactivity of 2-(dicyanomethylene)-1,3-indandione (1) towards 1,3-dicarbonyl compounds depends strongly on the nature of the CH acidic component. While the reaction with dimedone yields a spiro[chromene-4,2′indan] (2), indene-propellanes (3) are formed with acetoacetic esters. Adducts of acetylacetone and benzoylacetic acid ethyl ester to 1 have been identified as spiro[indan-2,2′-pyrans] (4). The propellane structure 3 is proven by X-ray analysis. Adducts 6 of CH acidic components with 3-(dicyanomethylene)-2-indolones 5 are used for reference measurements.
    Notes: 2-(Dicyanmethylen)-1,3-indandion (1) zeigt gegenüber 1,3-Dicarbonylverbindungen ein überraschend differenziertes Reaktionsverhalten, das von der CH-aciden Komponente abhängt. Während mit Dimedon ein Spiro[chromen-4,2′-indan] (2) entsteht, führt die Reaktion mit Acetessigsäure-ethyl- bzw. -tert-butylester zur Bildung der Inden-propellane 3. Die Addukte von Acetylacaton und Benzoylessigsäure-ethylester an 1 erweisen sich als Spiro[indan-2,2′-pyrane] (4). Die Propellanstruktur 3 wird durch eine Röntgenkristallstrukturanalyse abgesichert. Addukte 6 CH-acider Komponenten an 3-(Dicyanmethylen)-2-indolone 5 werden für Vergleichsmessungen verwendet.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220716
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 97
    Electronic Resource
    Electronic Resource
    Schwefel(IV)-Verbindungen als Liganden, IX: Molybdän-Rhodium-Zweikernkomplexe mit Schwefeldioxid als Brückenligand (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1623-1627 
    Details
    ISSN: 0009-2940
    Keywords: Binuclear complexes ; Molybdenum complexes ; Rhodium complexes ; Sulfur dioxide bridges ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur(IV) Compounds as Ligands, IX.  -  Binuclear Molybdenum-Rhodium Complexes with Sulfur Dioxide as a Bridging LigandThe hetero-binuclear complexes [MoRhCl(CO)3(μ-SO2)(μ-Ph2E1CH2E3Ph2)(μ-Ph2E2CH2E4Ph2)] (E = P, As, 1-4), [MoRhBr(CO)3(μ-SO2)(μ-Ph2PCH2PPh2)2] (5) and [MoRh(CN)(CO)3(μ-SO2)(μ-Ph2PCH2PPh 2)2] (6) are the first compounds which contain sulfur dioxide as a bridging ligand connected to two metal atoms from different groups of the periodic table. The synthesis starts from Mo(CO)3(NCMe)3 (7), which reacts with the chelating ligands Ph2PCH2PPh2 (dppm), Ph2AsCH2PPh2 (dapm), and Ph2AsCH2AsPh2 (daam) to give the mononuclear precursors Mo(CO)3-(η2-Ph2E1CH2E3 Ph2)(η1-Ph2E2CH2E4 Ph2) (9-12). With [Rh2Cl2(CO)4] these are converted to the binuclear complexes [MoRhCl(CO)4(μ-Ph2E1CH2E3 Ph2)(μ-Ph2E2CH2E4Ph 2)] (15-18). Reversible CO/SO2 exchange finally gives 1-4 and the analogous bromide 5, the cyanide complex 6 is obtained from 1 and NaCN in liquid ammonia.
    Notes: Die heteronuklearen Zweikernkomplexe [MoRhCl(CO)3(μ-SO2)(μ-Ph2E1CH2E3Ph2)(μ-Ph2E2CH2E4Ph2)] (E = P, As, 1-4), [MoRhBr(CO)3(μ-SO2)(μ-Ph2PCH2PPh2)2] (5) und [MoRh(CN)(CO)3-(μ-SO2)(μ-Ph2PCH2PPh 2)2] (6) sind die ersten Verbindungen, in denen Schwefeldioxid als Brückenligand an zwei Metallatome aus verschiedenen Gruppen des Periodensystems gebunden ist. Die Synthese geht von Mo(CO)3(NCMe)3 (7) aus, das mit den Chelatliganden Ph2PCH2PPh2 (dppm), Ph2AsCH2PPh2 (dapm) und Ph2AsCH2AsPh2 (daam) zu den einkernigen Vorstufen Mo(CO)3(η2-Ph2E1CH2E3 Ph2) (η1-Ph2E2CH2E4 Ph2) (9-12) umgesetzt wird. Daraus entstehen mit [Rh2Cl2(CC)4] die Zweikernkomplexe [MoRhCl(CO)4(μ-Ph2E1CH2E3Ph 2)(μ-Ph2E2CH2E4Ph2)] (15-18). Reversibler CO/SO2-Austausch ergibt schließlich 1-4 und das analoge Bromid 5, der Cyanokomplexe 6 wird aus 1 und NaCN in flüssigem Ammoniak erhalten.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220905
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 98
    Electronic Resource
    Electronic Resource
    Organosubstituierte 2,5-Dihydro-1,2,5-azasilaborole  -  Herstellungsmethoden und spektroskopische Charakterisierung (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1825-1850 
    Details
    ISSN: 0009-2940
    Keywords: Organoboranes, unsaturated ; Organosilanes, unsaturated ; Aminotriorganoborates ; Cyclization ; 2,5-Dihydro-organo-1,2,5-azasilaboroles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organosubstituted 2,5-Dihydro-1,2,5-azasilaboroles - Methods of Preparation and Spectroscopic CharacterisationThe compounds (E)-R22R2′ElIVC(R3) = C(R4)BR25 [(E)-1a to -g] are prepared from Na[R34,5BC ≡ CR3] with ClElIVR22R2′ [ElIV = Si, Ge, Sn] or from R22R2′SiC ≡ CR3 with BR34,5 (R4,5 = CH3, C6H5). The substituted silol 1z is obtained from (CH3)2Si(C ≡ CCH3)2 and B(C2H5)3, the mixture of (Z/E)-1t from (CH3)3SiC ≡ CH and B(C2H5)3. - ClSi(CH3)2C(CH3)2C(CH3)=C(C2H5)B(C2H5)Cl (C) reacts with LiN(CH3)2 to form (CH3)2NSi(CH3) 2C(CH3)2 C(CH3)=C(C2H5) B(C2H5)N(CH3)2 (E)-1n. - (E)-1a to (E)-1g or (E)-1a or (E)-1aGe and (E)-1aSn add MNH2 (M = Na, K) to yield the compounds MNH2-1, which react to the solid alkaline metal heterocycles M-2 after liberating R2H. From. (E)-1a or (E)-1b with LiNH2 the compounds (E)-C2H5CH=CR4Si(CH3)3 (A, B) are obtained. - On heating M-2a to M-2g eliminate R5H (C2H6) and smoothly from the solid compounds M-3, from which the heterocycles (4a-f) are prepared with CH3I. The 1-phenyl derivatives 5a, b are obtained from 4a,b with aniline. M-2c,d react with HCl to give the compounds 6c,d from which 7c,d are formed after C2H6 elimination. The 5-chloro compound 4i is used for the preparation of the heterocycles 4 with R5 = H, C(CH3)3, and N(CH3)2. - All compounds 1-7 are characterized by multinuclear NMR spectroscopy, the volatile compounds 1 and 4-7 also by their mass spectra.
    Notes: Die Verbindungen (E)-R22R2′ElIVC(R3) = C(R4)BR25 [(E)-1a bis -g] stellt man aus Na[34,5BC ≡ CR3] mit ClElIVR22R2′ [ElIV = Si, Ge, Sn] oder aus R22R2′SiC ≡ CR3 mit B34,5 (R4,5 = CH3, C6H5) her. Aus (CH3)2Si(C ≡ CCH3)2 und B(C2H5)3 sind das substituierte Silol 1z, aus (CH3)3)SiC ≡ CH und B(C2H5)3 im Autoklaven u. a. (Z/E)-1t zugänglich. - ClSi(CH3)2C(CH3) = C(C2H5)B(C2H5)Cl (C) und LiN(CH3)2 bilden (E)-1n. - (E)-1a bis (E)-1g bzw. (E)-1aGe und (E)-1aSn reagieren mit MNH2 (M = Na, K) zu den Additionsverbindungen MNH2-1, aus denen unter R2H-Abspaltung die festen Alkalimetall-Heterocyclen M-2 gebildet werden. (E)-1a und (E)-1b liefern mit LiNH2 (E)-C2H5CH=CR4Si(CH3)3 (A, B). - Aus M-2a bis M-2g erhält man beim Erhitzen unter R5H(C2H6)-Abspaltung glatt M-3, die mit CH3I zu den Heterocyclen (4a-f) reagieren. Die 1-Phenyl-Derivate 5a,b gewinnt man aus 4a,b mit Anilin. Aus M-2c,d sind mit HCl die Verbindungen 6c, d zugänglich, die unter C2H6-Abspaltung 7c,d liefern. Aus der 5-Chlor-Verbindung 4i stellt man die Heterocyclen 4 mit R5 = H, C(CH3)3 und N(CH3)2 her. - Sämtliche Verbindungen werden mit Multikern-NMR-Spektroskopie, die flüchtigen Verbindungen 1 und 4-7 auch massenspektrometrisch charakterisiert.
    Additional Material: 18 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221004
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 99
    Electronic Resource
    Electronic Resource
    Beiträge zur Chemie und Strukturchemie von Tris(diphenylphosphino)ethen und 1,1,4,4-Tetrakis(diphenylphosphino)-1,3-butadien (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1857-1861 
    Details
    ISSN: 0009-2940
    Keywords: Tris(diphenylphosphino)ethene derivatives ; 1,1,4,4-Tetrakis(diphenylphosphino)-1,3-butadiene derivatives ; Molybdenum complex ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry and Structures of Tris(diphenylphosphino)enthen and 1,1,4,4-Tetrakis(diphenylphosphino)-1,3-butadieneReaction of tris(diphenylphosphino)ethene (1), obtained by basecatalyzed hydrophosphorylation of Ph2PC≡CPPh2 with Ph2PH, with 2 equivalents of H3B · OC4H8 affords 1,1-bis(boranatodi-phenylphosphonio)-2-(diphenylphosphino)ethene (2). Methylation of 1 with MeI gives the monoquaternary salt 3, the molecular structure of which was determined by X-ray crystallography. A trisulfide 4 is available by treatment of 1 with elemental sulfur. - 1,1,4,4-Tetrakis(diphenylphosphino)-1,3-butadiene (5) was isolated as a byproduct in the synthesis of 1. 1,1,4,4-substitution was established by X-ray analysis of the tetrasulfide 6, obtained by treatment of 5 with elemental sulfur. Reaction of 5 with 2 equivalents of Mo(CO)6 yields the symmetrical, dinuclear complex 7.
    Notes: Das durch basenkatalysierte Addition von Ph2PH an Ph2PC≡CPPh2 erhaltene Tris(diphenylphosphino)ethen (1) reagiert mit 2 Äquivalenten H3B · OC4H8 zu 1,1-Bis(boranatodiphenylphosphonio)-2-(diphenylphosphino)ethen (2). Die Behandlung von 1 mit Iodmethan liefert neben nicht näher untersuchten Spaltprodukten das Monoquartärsalz 3, in dem die Oniumfunktion am mittleren der drei Phosphoratome auftritt. Die Kristallstruktur wurde röntgenographisch bestimmt. Bei Behandlung von 1 mit Schwefel entsteht das Trisulfid 4.  -  Bei der Darstellung von 1 wird als Nebenprodukt 1,1,4,4-Tetrakis(diphenylphosphino)-1,3-butadien (5) gebildet. Die Substitution in den 1,1,4,4-Positionen wurde ebenfalls durch Röntgenstrukturanalyse des Tetrasulfids 6 bestätigt, das durch Reaktion von 5 mit elementarem Schwefel darstellbar ist. 5, dessen Bildungsmechanismus noch nicht geklärt ist, reagiert mit 2 Äquivalenten Mo(CO)6 zum zweikernigen Molybdänkomplex 7.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221006
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 100
    Electronic Resource
    Electronic Resource
    Metallorganische Verbindungen der Lanthanoide, 50: N,N,N′-Trimethylethylendiamin-Derivate von Yttrium, Holmium und Lutetium (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1897-1900 
    Details
    ISSN: 0009-2940
    Keywords: Cyclooctatetraenyl complexes ; Cyclopentadienyl complexes ; Lanthanide amides ; Organolanthanides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organometallic Compounds of the Lanthanides, 50.  -  N,N,N′ - Trimethylethylenediamine Derivatives of Yttrium, Holmium, and LutetiumThe reactions of LiN(CH3)CH2CH2N(CH3)2 with YCl3, HoCl3, LuCl3, as well as with (C5H5)2YCl and (C4H9C8H7)LuCl result in the formation of the amides Li[Ln{N(CH3)CH2CH2N(CH3)2}4] [Ln = Y (1), Ho (2), Lu (3)], Li[(C5H5)2Y{N(CH3)CH2CH2N-(CH3)2}2] (4), and Li[(C4H9C8H7)Lu{N(CH3)CH2CH2N(CH3)2}2] (5), respectively. The 1H- and 13C-NMR spectra of the new compounds as well as the X-ray crystal structure of 2 are reported and discussed.
    Notes: LiN(CH3)CH2CH2N(CH3)2 reagiert mit YCl3, HoCl3 und LuCl3, sowie mit (C5H5)2LuCl und (C4H9C8H7)LuCl unter Bildung der homoleptischen Amide Li[Ln{N(CH3)CH2CH2N(CH3)2}4] [Ln = Y (1), Ho (2), Lu (3)], sowie von Li[(C5H5)2Y{N(CH3)CH2-CH2N(CH3)2}2] (4) und Li[(C4H9C8H7)Lu{N(CH3)CH2CH2N-(CH3)2}2] (5). Die 1H- und 13C-NMR-Spektren der neuen Verbindungen und die Einkristall-Röntgenstrukturanalyse von 2 werden beschrieben und diskutiert.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891221011
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...