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  • General Chemistry  (5,118)
  • Inorganic Chemistry  (3,865)
  • Fisheries
  • 2010-2014  (74)
  • 2000-2004  (405)
  • 1970-1974  (8,605)
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  • 1
    Publication Date: 2021-05-19
    Description: The genus Ctenochaetus is reportad in the waters of the Colombian Pacific based on two specimens of C. marginatus (Valenciennes) collected in 1993 at Gorgona Island (2°59' N, 78° 12' W). These specimens differ inseveral morphometric characteristics from thosepreviously examined. Such differences appear to be an artifact of the small number of specimens formerly examined and the consequent narrow ranges reportad. We suggest that temperature variability affects the distribution of C. marginatus in the tropical eastern Pacific.
    Description: El género es Ctenochaetus reportad en las aguas del Pacífico colombiano a partir de dos especímenes de C. marginatus (Valenciennes) recogidos en 1993 en la Isla Gorgona (2 ° 59 'N, 78 ° 12' W). Estos ejemplares difieren inseveral características morfométricas de thosepreviously examinados. Estas diferencias parecen ser un artefacto del pequeño número de muestras examinadas anteriormente y reportad los rangos estrechos consecuente. Sugerimos que la variabilidad de la temperatura afecta la distribución de marginatus C en el Pacífico tropical oriental.
    Description: Published
    Keywords: Fisheries ; Fisheries
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 2
    Publication Date: 2021-05-19
    Description: Over the last decade eutrophication of freshwater artificial reservoirs in Cuba occurred in parallel to oligotrophication of estuarine and coastal waters. These two processes influenced both freshwater and marine fisheries. A dramatic shift in species composition in freshwater fisheries has occurred, from dominance by cichlids (tilapia) to dominance by cyprinids. The high fishery yield from some reservoirs, and shift in species composition, seems related to progressive eutrophication of reservoirs by nutrient subsidies from different anthropogenic activities; particular those related to the size of urban areas within their watersheds. On the other hand, marine landings of estuarine-dependent species declined more significantly than for other groups associated with seagrass beds–coral reefs and oceanic waters. The ratio between catches of estuarine-dependent species and those associated with seagrass beds and coral reefs, decreased significantly over the last 20 years. The decrease in landings was more evident in typical estuarine species, such as shrimps (Litopenaeus schmitti and Farfantopenaeus notialis), mangrove oyster (Crassostrea rhizophorae) and mullets (Mugil spp.). River damming increased during the same period and is significantly correlated with these decreases. It is hypothesized that two different processes acted synergistically, leading to dramatic decreases of several orders of magnitude, in the catches of estuarine species over the last decade: the trapping of nutrients and sediments by river damming, and a drastic reduction in nutrient inputs from land-based sources due to reduced fertilizer use. These are postulated to have affected not only estuarine resources, but also the whole coastal ecosystem.
    Description: Durante la última década, la eutrofización de los embalses artificiales de agua dulce en Cuba se produjo en paralelo a oligotrophication de estuarios y costeras aguas. Estos dos procesos de influencia de agua dulce y la pesca marina. Un cambio dramático en la composición de las especies en la pesca de agua dulce se ha producido, de la dominación de los cíclidos (tilapia) a la dominación de ciprínidos. La alta producción de la pesca de algunos embalses, y el cambio en las especies composición, parece relacionada con la progresiva eutrofización de los embalses de las subvenciones de nutrientes de diferentes actividades antropogénicas, especialmente las relacionado con el tamaño de las zonas urbanas dentro de sus cuencas. Por otro lado, los desembarques de especies marinas de estuario-dependientes disminuyeron significativamente más que para otros grupos asociados con algas marinas Los arrecifes de coral-camas y las aguas oceánicas. La relación entre las capturas de las especies que dependen de los estuarios y las asociadas a las praderas marinas y Los arrecifes de coral, se redujo significativamente en los últimos 20 años. La disminución en los desembarques fue más evidente en especies típicas de estuarios, tales como camarones (Litopenaeus schmitti y Farfantopenaeus notialis), ostra de mangle (Crassostrea rhizophorae) y la lisa (Mugil spp.). El represamiento del Río aumentó durante el mismo período y se correlaciona significativamente con estas disminuciones. Se planteó la hipótesis de que dos procesos diferentes actúan de forma sinérgica, que conduce a una disminución drástica de varios órdenes de magnitud, en las capturas de las especies de estuario en la última década: la captura de nutrientes y sedimentos por represas río, y una reducción drástica de los aportes de nutrientes de fuentes terrestres, debido a la reducción del uso de fertilizantes. Se postula que han afectado no sólo a los recursos estuarinos, sino también todo el ecosistema costero.
    Description: Published
    Description: ríos
    Description: impactos antropogénicos
    Keywords: river ; Fisheries ; Eutrophication
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 3
    Publication Date: 2021-05-19
    Description: Se muestra la evolución de las capturas de las sierras y pintadas, se describen las 3 maneras en que las especies pueden quedar atrapadas en la redes de enmalles, así como también los tipos de redes (deriva, media agua y de fondo).
    Description: Published
    Description: Scomberomorus regalis
    Description: Scomberomorus maculatus
    Description: Scomberomorus cavalla
    Description: spanish mackerel
    Description: king mackerel
    Description: painted mackerel
    Description: enmalle
    Description: arte de pesca
    Keywords: Fisheries ; Artisanal fishing
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 4
    Publication Date: 2021-05-19
    Description: Published
    Description: Mugil curema
    Description: Mugil liza
    Description: Mugil cephalus
    Description: Gerres cinereus
    Description: patao
    Description: coastal lagoons
    Keywords: Mullet fisheries ; Fisheries
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 5
    Publication Date: 2021-05-19
    Description: Production of mangrove oyster (Crassostrea rhizophorae Guilding, 1828), north of Villa Clara, Cuba Province, tends to decline since 1980, accentuating from 2003 on. Despite regulations to protect the resource, minimum legal size and catch closures, the year 2008 presents the landing smaller volumes of the past 50 years. An analysis of the variability of catches in relation to natural and human factors, allows for precipitating causes of low productivity of this fishery resource; between the most representatives are expanding storage capacity of river water, salinity increment, the increase in frequency and intensity of hurricanes and the mismanagement of the extraction of oyster.
    Description: La producción de ostión de mangle (Crassostrea rhizophorae, Guilding, 1828), al norte de la provincia de Villa Clara, Cuba, tiende a la disminución desde de 1980, acentuándose a partir del año 2003. A pesar de regulaciones para la protección del recurso, talla mínima legal y vedas de captura, el año 2008 presenta los menores volúmenes de desembarque de los últimos 50 años. Un análisis de la variabilidad de las capturas, en relación con factores naturales y antrópicos, permite establecer causas desencadenantes de la baja productividad de este recurso pesquero; las más representativas son, la ampliación en la capacidad de embalse de aguas fluviales, aumentos de la salinidad, el incremento en la frecuencia e intensidad de los huracanes y un manejo inadecuado de la actividad extractiva de ostión.
    Description: Crassostrea rhizophorae, Cuba
    Keywords: Fisheries ; Environmental effects ; Fisheries
    Repository Name: AquaDocs
    Type: Preprint
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  • 6
    Publication Date: 2021-05-19
    Description: Las capturas de langosta espinosa Panulirus argus (Latreille, 1804) en Cuba alcanzaron sus mayores volúmenes en la década de 1980 con un promedio anual de 11565 ton. En la década de 1990, la captura descendió a un promedio de 9327 ton, lo cual se ha visto agudizado entre 2000 y 2007 con un promedio de 6262 ton y una mayor variabilidad de las capturas, a pesar de un perfeccionamiento del sistema de manejo pesquero dado por: la disminución del esfuerzo pesquero y de la tasa de mortalidad por pesca desde 1999, el aumento del período de veda desde 2001 y el incremento gradual de la talla mínima legal de captura a partir de 2004. Los análisis más recientes sobre el estado de esta pesquería fueron presentados en el Quinto Taller Regional sobre la Evaluación y la Ordenación de la Langosta Común del Caribe en septiembre 2006 (Puga et al, 2006; FAO, 2007), donde se reconoció por la comunidad científica especializada que la pesquería de langosta cubana se encontraba bien manejada y plenamente explotada (no sobre- explotada) y se concluyó que además de la mortalidad por pesca, otros factores ajenos al sector pesquero estaban produciendo afectaciones en la abundancia del recurso, al causar daños al hábitat 1 en zonas de cría, influyendo negativamente por esta vía sobre el reclutamiento y la producción de langostas. Entre estos aspectos para Cuba se señalaron: la mayor frecuencia e intensidad de huracanes durante el último decenio, el desarrollo de las zonas costeras, la construcción de presas en las cuencas de captación de los ríos y de carreteras en el Archipiélago Sabana-Camagüey comunicando la isla principal con los cayos y los cayos entre si (pedraplenes).
    Description: Published
    Keywords: Fisheries ; Lobster fisheries ; Fisheries ; Environment management ; Recruitment ; Coastal zone management
    Repository Name: AquaDocs
    Type: Book Section
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  • 7
    Publication Date: 2021-05-19
    Description: Se efectúa un estudio de la fauna acompañante del Mero, Epinephelus morio, en la pesquería con palangre de fondo del Banco de Campeche, México, durante el periodo 1987-2009. En la investigación se consideró información de 32 cruceros de investigación realizados en la etapa como parte del convenio pesquero firmado por Cuba y México para la evaluación sistemática del recurso. Se determinó la composición por especie y talla de las capturas, sus variaciones en la abundancia relativa, estructura de tallas, así como el índice de diversidad de Brillouin, la riqueza de especies (Margalef, 1980), la dominancia numérica y la constancia, estas ultimas valoradas según el esquema propuesto por Bodenheimer (1955). Se encontró que la fauna acompáñate de E. morio esta representada por 69 especies, agrupadas en 3 clases y 12 órdenes. De ellos, el orden mejor representado lo constituyó Perciformes con las familias Serranidae, Lutjanidae, Scombridae, Carangidae y Haemulidae como las más abundantes en número. Dentro de estas, dominaron las especies L. campechanus y O. chrysurus, apreciándose que las entidades mejor representadas son, L. campechanus (100%), O. chrysurus (96,87%) y M. bonaci (73,2%). Los largos medios observados se encontraron por encima de las tallas de primera maduración reportadas en la literatura. Sólo E. nigritus y L. analis presentaron individuos inmaduros. Se reportan tallas máximas superiores a las reportadas en la bibliografía en M. interstitiaslis (150cm), M. bonací (155cm) y E. nigritus (125cm). Se determinó que el rendimiento (cpue) y la diversidad de la fauna acompañante poseen una relación inversa con la disminución de la biomasa de mero. Por su parte, la diversidad y riqueza de especie presentaron sus mayores valores concordando con las temporadas de lluvias.
    Description: Mero Epinephelus morio, fauna acompañante, Banco de Campeche, México,
    Keywords: Fisheries ; Fauna ; Fisheries ; Fauna
    Repository Name: AquaDocs
    Type: Preprint
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  • 8
    Publication Date: 2021-05-19
    Description: Se presentan los resultados de monitoreo de las poblaciones comerciales de cobo en el área comprendida entre los cayos El Cabezo y Boca de Sagua (220 49`N--230 04`N y los 790 35W—800 07´ `W), plataforma Norte de la Provincia de Villa Clara. A partir de los resultados de las densidades de individuos como índice de la abundancia y la estructura poblacional encontrada, se propone un potencial de captura de 104 TM (peso entero). Además, se definen las medidas de manejo para el uso sostenible del recurso Eustrombus gigas en esta zona. El aprovechamiento en carne desembarcada (Eviscerada y sin manto) para individuos adultos con talla comercial se obtiene por un factor de 0,074 (7,4%) del peso entero, que representa 7,7 TM. Se excluye el área protegida desde Las Picúas hasta Cayo Cristo.
    Description: cobo (Eustrombus gigas), Caibarién, Villa Clara
    Keywords: Monitoring ; Fisheries management ; Fisheries
    Repository Name: AquaDocs
    Type: Preprint
    Format: 4
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  • 9
    Publication Date: 2021-05-19
    Description: La Commission Sous Régionale des Pêches (CSRP), qui est un organisme intergouvernemental de coopération halieutique dont l’objectif global est l’harmonisation à long terme, des politiques des pays membres en matière de préservation, de conservation et d'exploitation durable de leurs ressources halieutiques et le renforcement de leur coopération au profit du bien-être de leurs populations respectives, a obtenu par l’intermédiaire de la Banque mondiale, un Don du Fonds pour l’Environnement Mondial (FEM) et du Gouvernement du Japon, pour la préparation d’un Projet Régional des Pêches en Afrique de l’Ouest (PRAO) pour trouver une solution à la problématique susvisée. Ce projet implique 9 pays côtiers: la Mauritanie, le Cap Vert, le Sénégal, la Gambie, la Guinée Bissau, la Guinée, le Sierra Léone (Etats membres de la CSRP), ainsi que le Libéria et le Ghana. Le PRAO comprend trois composantes : (1) Bonne Gouvernance et Gestion Durable des Pêches ; (2) Réduction de la Pêche Illicite ; (3) Augmentation de la Contribution des Ressources Halieutiques dans les Economies Locales (incluant la réalisation d’infrastructures et équipements dans les pêcheries). Certes, les activités prévues dans le cadre du PRAO sont pressenties pour contribuer au développement du secteur de la pêche dans les pays ciblés et apporter des bénéfices aux populations locales. Toutefois, elles pourraient engendrer dans certains cas des effets négatifs aux niveaux environnemental et social (notamment celles prévues dans la composante 3), si des mesures adéquates ne sont pas prises au préalable. Afin de minimiser ces effets défavorables, il a été requis l’élaboration de la présente Evaluation Environnementale et Sociale (EES).
    Description: Commission Sous Régionale des Pêches (CSRP)
    Description: Published
    Description: ressource marine, ressource côtière, politique de pêhce, environnement, qualité des produits, pollution, gestion des pêches,aire marine protégée
    Keywords: Marine resources ; Fisheries ; Fishery management ; Coastal fisheries ; Quality assurance ; Environment management ; Marine resources ; Fisheries ; Fishery management ; Coastal fisheries ; Coastal zone ; Fishery regulations ; Fishery economics ; Marine pollution ; Quality control ; Illegal fishing ; Fishery organizations ; Quality assurance
    Repository Name: AquaDocs
    Type: Report
    Format: 111
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  • 10
    Publication Date: 2021-05-19
    Description: Ce travail représente une contribution à l'étude de l'activité de pêche hauturière dans le gouvernorat de Médenine, particulièrement, au niveau du port de Zarzis ; durant la période (juin 2005-juin 2006). Il consiste à réaliser, grâce à des enquêtes menées au port, deux types d'analyses : une analyse quantitative afin de déterminer les débarquements saisonniers moyens des espèces les plus débarquées par la pêche hauturière et une analyse qualitative pour établir les structures démographiques des espèces les plus exploitées dans la région. Les résultats obtenus ont montré que, durant la période d'étude, les principales espèces débarquées par la pêche hauturière sont la sardinelle, le maquereau, le saurel, le rouget blanc, le pageot, la thonine, la seiche et la crevette royale. En examinant les débarquements saisonniers moyens des espèces les plus débarquées par type de pêche, nous avons remarqué que deux ou trois espèces dominent pour chaque saison. De plus, l'analyse des structures démographique des apports a montré que la majorité des individus débarqués sont matures, à l’exception du maquereau dont les captures sont constituées d’individus immatures, surtout pendant les saisons d’été et d’automne.
    Description: This work represents a contribution to the study of the offshore fishing activity in the governorate of Medenine, particularly at the port of Zarzis, during the period (june 2005-june 2006. It is to realize, through surveys conducted at the port, two types of analyzes: a quantitative analysis to determine the average seasonal landings of most landed species by fishing offshore units and qualitative analysis to determine the demographic structure of the most exploited species in the region. The obtained results showed that during the period of study, the main landed species by offshore fishing are sardinella, mackerel, horse mackerel, white mullet, sea bream, skipjack tuna, cuttlefish and the caramote prawn. By examining the average seasonal landings of the most landed species, we noticed that, for each season, two or three species dominate. Furthermore, analysis of demographic structures of the landings showed that the majority of landed individuals are mature, with the exception of mackerel catches which are composed of immature individuals, especially during the seasons of summer and autumn.
    Description: Published
    Description: analyse qualitative
    Description: pêche hauturière
    Keywords: Quality analysis ; Offshore ; Fisheries
    Repository Name: AquaDocs
    Type: Proceedings Paper , Refereed , Meeting abstract
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  • 11
    Publication Date: 2021-05-19
    Description: El presente artículo da una descripción detallada de la elaboración y del "curado" de cuerdas de curricán, utilizadas anteriormente para la pesca en Taganga, un pueblo pescador en la costa norte de Colombia. Antes del "curado", estas cuerdas de fibras de algodón y de fabricación industrial, eran o destorcidas o torcidas a mano nuevamente, o tensionadas y envueltas con una cuerda más delgada del mismo material. El "curado" que siguió a estas operaciones se efectuó tanto en una cocción de corteza de las raíces zanconas de mangle, y/o por medio de un frote de estas cuerdas con los hypocotylos del mismo árbol (Rhizophora manglr). Por medio de las técnicas aquí descritas, los pescadores aspiraban a aumentar la resistencia de sus aparejos de pesca en el agua de mar.
    Description: The present paper gives a detailed description of the elaboration and curing of curricán Unes, formerly used as fishing lines in Taganga, a small fishing village on the northem coast of Colombia. These lines, made of cotton fibers and produced industrially, were disassembled and then retwisted by hand, or tightened and then carefully covered with a thinner string of the same material. The curing {"curado") that followed these operations was achieved by immersion of the lines into a boiled infusión of the bark of the prop roots of mangroves (Rhizophora mangle) and/or a rinsing with the hypocotyls of the same trees. By means of the techniques mentioned, the fishermen sought to improve the resistance of their fishing gear to sea water.
    Description: Published
    Keywords: Fisheries ; Fishing ; Gear construction ; Fisheries ; Fishing
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 12
    Publication Date: 2021-05-19
    Description: During a 3 week study, a total of 55 individuals of the redlip blenny (Ophioblennius atlanticus) were observed for at least two 15-minute periods, and several for ten of such periods. The sizes of their territories were estimated, the color pattern of each specimen an intra and interspecific interactions were recorded. The mean territory size of the redlip blenny in the study area appeared to be greater than that of these blennies studied in Curacao and Barbados by NURSALL (1977), the difference reflecting perhaps different methods of identifying the territories or a lower density of O. atlanticus in the Santa Marta área. Territories did not appear to be as consistently defended at the study area as at Barbados/Curacao and our impression ¡s that individuals holding large territories are less likely to defend their borders. It seems possible that light colored individuals are protected by their coloration from attack by dark colored territory owners. In territorial defense the redlip blennies grabbed each other tighthy by the mouth and struggled in this position repeatedly for about 15 seconds. Interspecific antagonism was common in the present study, the redlip blennics defended their territory frequently against Eupomacentrus dorsopunicans or E. partitus.
    Description: Durante un estudio de tres semanas, un total de 5 i individuos del bií'nido Ojih'toblcnnius atlnniicur. fueron observados por lo menos durante dos períodos de 1 í minutos para cada individuo y en algunos casos hasta por 10 de estos periodos. Se estimó el área de sus respectivos territorios y se tomó notí de los patrones de coloración de cada espécimen y de las relaciones intra e interespecificas de ellos. El tamaño promedio del territorio de estos blénidos resultó ser mayor que el de los respectivos territorios estudiados por NURSALL (1977) en Curacao y Barbados. Esta diferencia posiblemente se debe a un método diferente de definir los territorios o refleja una densidad menor de la población de O. aílanticus en Santa Marta, Los territorios del área fueron defendidos con menor intensidad a como lo fueron los de Barbados/ Curacao y es nuestra impresión que individuos ocupando un territorio extenso tienden a defender sus límites en menor grado. El color claro de algunos individuos probablemente los protege de agresiones por parte de individuos de color oscuro. En el acto de defensa territorial intraespecífica, los blénidos se agarran por sus bocas y se sacuden mutuamente durante aproximadamente 15 segundos , pudiéndose repetir esti varias veces. Con frecuencia se observarondefensas de los territorios dirigidas hacia los peces doncella Eupomacentrus dorsopunicnas y E. partitus.
    Description: Published
    Keywords: Fisheries ; Biology ; Fisheries ; Biology
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 13
    Publication Date: 2021-05-19
    Description: Se registra por primera vez el fenómeno de albinismo en la familia de peces Muraenesocidae, con base en dos ejemplares de Cynoponticits savanna capturados en la Península de la Guajira. Caribe colombiano.
    Description: The phenomenom of albinism is reported for the first time in che fish family Muraenesocidae. Two anomalous individuals of Cynoponticus savanna were collected from the Guajira Península colombian Caribbean.
    Description: Published
    Keywords: Fisheries ; Albinism ; Fisheries ; Albinism ; New records
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    Type: Journal Contribution
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  • 14
    Publication Date: 2021-05-19
    Description: Se muestran las capturas históricas de la biajaiba (1935-2000), la evolución de las capturas del pargo (una de las especies de mayor interés económico en Cuba). Se evalúa la utilización de éstas artes de pesca en especies comerciales y su implicación con daños al medio ambiente. Se tiene en cuenta que los pargos criollos, la biajaiba y el caballerote representan el 20 % de las capturas.
    Description: Published
    Description: pesquería artesanal
    Description: cubera
    Description: cherna criolla
    Description: pesca del alto
    Description: pargo
    Description: rabirrubia
    Description: caballerote
    Description: biajaiba
    Keywords: Fisheries ; Artisanal fishing
    Repository Name: AquaDocs
    Type: Journal Contribution , Non-Refereed , Article
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  • 15
    Publication Date: 2021-05-19
    Description: Se ha estudiado la variación anual de la condición de la lisa Mugil incilis Hancock en la Ciénaga Grande de Santa Marta (CGSM), la mayor laguna costera del Caribe Colombiano, haciendo énfasis en la influencia ejercida por factores ambientales como la salinidad, la temperatura y la transparencia de las aguas sobre la condición de esta especie de Mugilidae. Las diferencias estacionales observadas en la condición de M. incilis están evidentemente relacionadas con su desarrollo gonadal y dependen de la disponibilidad de alimento. La dieta de M. incilis se basa en detritos y su suministro de alimento parece ser muy afectado por el aporte fluvial a la CGSM, el cual es también responsable de los cambios en la salinidad de la laguna, esto explica la relación inversa (r = -0.82) hallada entre la salinidad y la condición de M. incilis expresada por C = 0.9949 - 0.0057 S(°/oo). La variación anual de la salinidad sigue un patrón rítmico de cambios estacionales, no precisamente "in situ", sino en regiones continentales distantes: las cabeceras de los tributarios de la CGSM. Estas lisas desovan en aguas del Caribe adyacente a la CGSM y su período de migración (dic-marzo) comienza con su mejor condición física, y retornan a sus áreas de alimentación en la CGSM 2 a 4 semanas después, hasta el final de la migración, con su condición mínima ya que al parecer estas lisas no se alimentan durante su migración de desove. No se observaron cambios relacionados con las variaciones de la temperatura. Las aguas más turbias coincidieron con los sitios de alimentación de M. incilis.
    Description: The annual variation in condition of the mullet Mugil incilis Hancock has been studied in the Ciénaga Grande de Santa Marta (CGSM). The largest coastal lagoon on the Colombian Caribbean, with emphasis on the influence of such environmental factors as salinity, temperature and transparence of the waters on the condition of this species of Mugilidae. Seasonal differences observed in condition of M. incilis are evidently related to gonadal development and depend on food availability. The diet of M, incilis is based on detritus and its food supply seems to be very influenced by river discharge which also accounts for the salinity changes in the lagoon. this explains the in verse correlation (r = -0.82) found between salinity and condition of the mullets expressed as C = 0.9949 - 0.0057 S (°/oo). Annual salinity variation follows a rhythmic pattern of seasonal changes. not precisely "in situ", but in distant continental regions: the headwaters of the tributarles of the CGSM. These mullets spawn in Caribbean waters adjacent to the CGSM and their migración period (Dec-March) begins with their best physical condición, returning to their feeding áreas in the CGSM 2 or 4 weeks lacer, until the end of the migración, with their lowest condition since these mullets apparently do not feed at all during the spawning migration. No change related to temperature variations was observed. and turbid waters were the rule in M. incilis feeding sites.
    Description: Published
    Description: Mugil incilis
    Keywords: Fisheries ; Estuaries ; Ecology ; Coastal lagoons ; Fishery biology ; Fisheries ; Coastal lagoons ; Estuaries ; Fishery biology ; Ecology
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 16
    Publication Date: 2021-05-19
    Description: Un análisis de los datos arqueológicos e históricos sobre la pesca en Cuba muestra que el impacto de la población aborigen sobre los recursos pesqueros no fue significativo debido a su baja densidad poblacional y a las tecnologías de pesca. El interés por el oro, el tamaño de la población, las limitaciones tecnológicas para la pesca y preservación de las capturas así como las preferencias dietéticas de los españoles todas indican que la pesca tampoco fue una actividad económica importante durante los tres siglos que siguieron a la llegada de Colón. Las preferencias por la carne de res y el bacalao salado y la baja tasa de crecimiento poblacional durante el período colonial determinaron que la mayor parte de los recursos pesqueros, con la excepción del manatí y las tortugas marinas, permanecieran prácticamente inexplorados durante varios siglos después de la Conquista. Los datos estadísticos e históricos revelan que la pesca experimentó un rápido crecimiento desde 1950 y este patrón parece ser una característica común en el Caribe así como en otras partes del mundo. Las presiones sobre la vida marina fueron más evidentes en la segunda mitad del siglo xx cuando el crecimiento poblacional, las mejoras tecnológicas y las demandas del mercado aceleraron el sector pesquero así como la urbanización en la mayoría de los países del caribe.
    Description: Published
    Keywords: Integrated management ; Fisheries
    Repository Name: AquaDocs
    Type: Proceedings Paper , Refereed , Article
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  • 17
    Publication Date: 2021-05-19
    Description: Se describen y se ilustran seis especies de parásitos pertenecientes a la familia Acanthocolpidae encontradas en 19 especies de peces en su mayoría de considerable importancia económica. El estudio taxonómico de estos parásitos se realizó en la Ciénaga Grande de Santa Marta, al norte de Colombia, desde Enero de 1978 hasta Junio de 1979.
    Description: A taxonomic study for parasites found in 19 mostly economically important fish species was carried out in ihe Ciénaga Grande de Santa Marta (Northern Colombia) from January 1978 uritil June 1979. Six species of fish parasites belonging to the family Acanthocolpidae are described and illustrated herein.
    Description: Published
    Keywords: Fisheries ; Ecology ; Parasites ; Parasites ; Fisheries ; Ecology
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 18
    Publication Date: 2021-05-19
    Description: En 1987, se inicia un programa de muestreos biológicos del calamar argentino ///ex argentinas a bordo de barcos comerciales de la flota cubana de pesca que operan en la plataforma patagónica. La talla de los organismos para ambos sexos presenta un comportamiento estratificado por profundidades, los ejemplares de mayor tamaño se encuentran a profundidades superiores y viceversa, lo cual se ajusta a una recta de regresión (r2 = 0.88; a = 0.05). Las hembras alcanzaron largos promedio del manto superior a los machos, incrementándose la presencia de machos en las capturas desde enero a abril. Se estimaron los largos promedio de primera maduración, como 20.5 y 26.5 cm de largo del manto para machos y hembras respectivamente. Se observó un aumento de la proporción de individuos maduros de febrero a abril, haciéndose más marcado este fenómeno en los machos, que en su mayoría presentaban abundantes espermatóforos en el saco. Se obtuvo la relación largo-peso para hembras y machos y para la combinación de ambos sexos.
    Description: In 1987 a program for the biological sampling of squid ///ex argentinas, was begun on board of a fishing ship belonging to the Cuban Fisheries-Fleet, wich operates in the Patagonian Shelf. The lengths of both sexes presented a estratified pattern with individuals of larger size found in higher depths and viceversa; this pattern is adjusted to a regression line (r2 = 0.88; a = 0.05). Pernales reached average length larger (han males and the rate of males in catches increased from january to april. The first maturation average length was estimated about 20.5 cm for males and 26.5 cm for females. An increase of the rate of mature individuals was observed between february and april emphazasing ¡n males which showed abundant espermatophores in the sac.
    Description: Published
    Description: squid, Flota Cubana
    Keywords: Fisheries ; Squid culture ; Biological charts ; Biological data ; Fisheries ; Squid culture
    Repository Name: AquaDocs
    Type: Journal Contribution
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  • 19
    Publication Date: 2021-05-19
    Description: A yield per recruit model has been used to compare the effects of mesh size increment on the yields and revenues of the fisheries of Cameroon under two different cases. Case 1 assumes the commercial fishery to move from the exploitation of three age-groups to two age-groups with no interactions with the artisanal fishery, whereas Case 2 takes into account these interactions. The difference in the percentage increase of yield per recruit between case 1 and case 2 is 61% at current fishing (46% and 18% yield per recruit increment in cases 1 and 2 respectively). The usually accepted long-term yield per recruit increment with increase of age at first capture (with a single non-interacting fisheries) is, in this case, cancelled out. However, the revenues increase by 72% and 63% in cases 1 and 2 respectively. Therefore the economic approach, compared with purely biological analyses, is more convincing. In general, as fisheries always interact, a single-fishery management approach should not be the rule as it is at present; management strategies should consider interactions between different fisheries and be based on their economic performances and not, as said earlier, on purely biological considerations. This is because a biological approach to fisheries management will, at best, be modified by economic factors, or, at worst, be ignored totally in favour of economic policies.
    Description: Published
    Keywords: Biology ; Fisheries ; Biological interaction ; Sciaenidae ; Fisheries development ; Fishery management ; Yield/recruit ; Commercial fisheries ; Artisanal fishing
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 20
    Publication Date: 2021-05-19
    Description: La pêche au Sénégal joue un rôle économique et social très important par une contribution globale de près de 11% du PIB primaire et 2,3% du PIB total. Elle occupe de façon directe et indirecte environ 600 000 personnes, soit près de 17% de la population active selon la DP M. Cependant ces dernières décennies, les études ont montré que le secteur traverse une crise aiguë se traduisant par une raréfaction croissante des ressources, notamment les espèces nobles qui ont une forte valeur commerciale. Cette crise est due entre autres à une surexploitation de ces ressources qui est le résultat d’un manque de maîtrise de l’effort de pêche surtout pour les pêcheries artisanales (80% des débarquements et plus de 60% des approvisionnements des industries de la place) au regard du volume de ressources disponibles. Ce manque de maîtrise est dû essentiellement par un défaut du suivi contrôle et surveillance au niveau de la pêche artisanale par l’Etat, qui n’a pas les moyens humains et matériels pour appliquer des mesures de gestion, qui pour la plupart ne sont pas adaptées aux réalités des acteurs à la base. L’objet de cette étude est d’analyser une nouvelle approche axée sur la surveillance participative basée sur l’émergence d’initiatives locales de cogestion au niveau des quatre (04) sites du programme GIRMaC que sont ; Ouakam, Ngaparou, Foundiougne et Bétenty. Il ressort de cette étude que : • Le secteur de la pêche traverse une crise aiguë due principalement selon les acteurs à un défaut de suivi, contrôle et surveillance tel que appliqué actuellement ; • L’approche de cogestion avec des bases juridiques cohérentes, comme le propose le programme GIRMaC peut être un moyen viable pour solutionner à la crise que traverse la pêche ; • D’une part le système Suivi Contrôle et Surveillance coûte cher, d’autre part que ces coûts sont fortement amoindris lorsque les acteurs participent à l’effort de surveillance, par une démarche de surveillance participative en cogestion.
    Description: Président : Omar Thiom THIAW, Professeur UCAD Membres : • Niokhor DIOUF, Chercheur IUPA. • Luis Tito Morais, Chercheur IRD Dakar. • Djiby THIAM, Chercheur GIRMac
    Description: Published
    Description: surveillance; contrôle; cogestion; effort de pêche; pêcherie; surexploitation; biodiversité; pêche artisanale
    Keywords: Ocean surveillance ; Ecosystem management ; Fishing effort ; Overexploitation ; Biodiversity ; Artisanal fishing ; Fisheries
    Repository Name: AquaDocs
    Type: Theses and Dissertations , Master thesis
    Format: 87
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  • 21
    Publication Date: 2021-01-30
    Description: The first meeting of the South West Indian Ocean EAF Regional Task Group (RTG) was held in Mombasa, Kenya, from 27 to 30 January 2009, together with an ecological risk assessment methodology workshop. It was attended by 20 partic ipants from the South West Indian Ocean (SWIO) countries, the South West Indian Ocean Fisheries Project (SWIOFP), the Agulhas and Somali Currents Large Marine Ecosystems (ASCLME) project, the Scientific Committee of the South West Indian Ocean Fisheries Commission, the United Nations Environment Programme (UNEP)/Nairobi Convention Implementation Unit, the African Union Commission and FAO. The RTG is an implementation structure under the EAF-Nansen project GCP/INT/003/NOR and serves as the forum for training in ecological risk assessment that is the methodology used for the identification and prioritization of issues requiring management attention. The main objectives of the meeting and workshop we re to discuss and facilitate key processes and activities for the implementation of the ecosystem approach to fisheries management in the South West Indian Ocean region including the modalities for the formation and functioning of the RTG and National Task Groups (NTGs). It was explained that, to be able to achieve the objectives of implementing an ecosystem approach to fisheries at the national level, certain key structures have to be in place including the NTG with representatives of key stakeholders in a given fishery and that would take the lead in the process. An overview of the key concepts and process of the ecological risk assessment methodology were clarified. Participants were also introduced to the preparation of EAF baseline reports to be used as initial input for the work on ecosystems approach to fisheries. It was explained that the preparation of the report is to be led by national and regional experts and overseen by the NTG. For the exercises the participants worked in three subgroups formed during the meeting with each group selecting a chairman who moderate d the discussions and a rapporteur. The participants expressed satisfaction with the development of a communication strategy for the project and especially with the participatory approach used.
    Description: FAO, NORAD, Institute of Marine Research
    Description: Published
    Description: National task groups
    Description: Regional task groups
    Description: Ecosystem Approach to Fisheries
    Keywords: Ecosystems ; Fisheries ; Ecosystems ; Fishery resources ; Fisheries management
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 36
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  • 22
    Publication Date: 2021-05-19
    Description: Published
    Description: espéces pélagiques
    Description: sardine
    Description: pêche industrielle
    Keywords: Fisheries ; Pelagic fisheries ; Industrial fish ; Fish products ; Fishing industry ; Fishing fleet
    Repository Name: AquaDocs
    Type: Journal Contribution , Non-Refereed , Article
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  • 23
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    Nigerian Institute for Oceanography and Marine Research | Lagos, Nigeria
    Publication Date: 2021-01-30
    Description: Published
    Description: Fisheries newsletter
    Keywords: Fisheries ; Marine sciences ; Fisheries literature
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 30pp.
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  • 24
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    Nigerian Institute for Oceanography and Marine Research | Lagos, Nigeria
    Publication Date: 2021-01-30
    Description: Published
    Description: Fisheries newsletter
    Keywords: Fisheries ; Marine sciences ; Fisheries literature
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 34pp.
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  • 25
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    Nigerian Institute for Oceanography and Marine Research | Lagos, Nigeria,
    Publication Date: 2021-01-30
    Description: Published
    Description: Fisheries newsletter
    Keywords: Fisheries ; Fisheries literature
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 11pp.
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  • 26
    Publication Date: 2021-05-19
    Description: Unpublished
    Description: conservation
    Description: chaine froide
    Description: poisson
    Keywords: Food conservation ; Fisheries ; Fish conversion ; Conservation (fishery products) ; Glass ; Fisheries
    Repository Name: AquaDocs
    Type: Journal Contribution , Non-Refereed , Article
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  • 27
    Publication Date: 2021-05-19
    Description: Published
    Description: Pêche
    Description: Senneur
    Keywords: Seining ; Fisheries ; Fisheries ; Seiners
    Repository Name: AquaDocs
    Type: Journal Contribution , Refereed , Article
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  • 28
    Publication Date: 2021-05-19
    Description: ACDI;CRDI; République Française, Ministère des Affaires Etrangéres; CDE; Enda Graf Sahel;
    Description: Conseil Info MPEA, Projer d'Accés à l'information et au Conseil pour les microet petites entreprises agroalimentaires; Projet d'Appui aux Opérateurs/trices de l'Agroalimentaires (PAOA); Cintech Agroalimentaire; Groupe de Recherche et d'Echanges Technologiques (GRET); Enda GRaf Sahel; SNC-LAVALIN International
    Description: Published
    Description: transformation; transformation artisanale; échantillonage; collecte de données; commercialisation
    Keywords: Processing fishery products ; Biological sampling ; Data collections ; Marketing and distribution ; Fisheries
    Repository Name: AquaDocs
    Type: Theses and Dissertations , Master thesis
    Format: 41
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  • 29
    Publication Date: 2021-05-19
    Description: Français - Les traits essentiels de la côte sénégalaise, repères historiques de la pêche, communautés de pêcheurs, caractéristiques des flottes et modes d’accès à la ressource et d’interaction sont analysés. Les caractéristiques, tendances décroissantes de l’abondance,niveaux d’exploitation, mesures d’aménagement, relations interspécifiques, changements potentiels et sources de variation des stocks démersaux côtiers sont précisés. Les notions de tactiques et stratégies de pêche sont passées en revue, conceptualisées puis étudiées.Le modèle «Dynamique Conjointe Exploitation Ressource» utilisé repose sur la définition de 4 typologies. L’utilisation de méthodes de classification et de connaissances d’experts conduit à considérer 32 stocks, 31 strates, 82 tactiques et 25 flottilles artisanales et chalutières. Les typologies sont articulées avec la prise en compte de paramètres relatifs à l’économie, aux stocks, flottilles et règles de décisions. L’ajustement est satisfaisant en partie. Toutefois, le modèle garde son importance en matière de prospective et d’objectifs à atteindre via la définition de variables de contrôle. Notre travail peut être considéré comme une esquisse invitant à un groupe de travail élargi aux experts des institutions halieutiques nationales voire, sous-régionales. Des propositions sont faites sur les bases de données, les licences de pêche et l’étude des tactiques et stratégies à mener suivant des pas de temps raisonnables pour tenir compte du grand dynamisme des pêcheries. Dès lors qu'il s’agit de caractériser l'impact de la pêche sur l'écosystème, ces travaux sont des éléments essentiels des recherches à faire sur la dynamique des écosystèmes exploités. English - The essential features of the Senegalese coast, fisheries history, fishermen's communities, artisanal and trawling fleet’s characteristics and their way of accessing to the resource and interactions are described. The characteristics, evolutionary tendencies of abundance, level of exploitation, measures of fisheries management, interspecific relationship, potential evolutionary changes and sources of variation of coastal demersal stocks are specified. Tactics and strategies are reviewed, conceptualized and studied. We used the model "Dynamique Conjointe Exploitation Ressource" which lies on 32 stocks, 31 strata, 82 tactics, 25 fleets and several other parameters dealing with stocks, fleets, economy and making decision rules. The adjustment is partially satisfactory but the model is of great interest for prospective studies and objectives to reach once defined variables of control. Our work is an outline calling for an enlarged working group implying national or sub regional fisheries institutional experts. Tactics and strategies studies, re-actualized in artisanal fisheries, are performed for the first time in industrial fisheries. The typological approach is simple, pertinent, efficacy and fast. Propositions are made relatively to databases, fishing licenses and tactics and strategies studies that should be implemented according to a reasonable time steps in order to take into account the big dynamism of the Senegalese fisheries. As it is intended to characterize fisheries impact on ecosystem, these works are one of essential research elements on the dynamic of exploited ecosystems.
    Description: Published
    Description: pêcherie; démersale côtière; modélisation; stocks; écosystème; communauté de pêcheurs; eaux continentales; eaux marines; saison hydrologique; pêcheur; flottille; crevettier; capture; aménagement des pêcheries; pêche chalutière; pêche artisanale; licence de pêche; permis de pêche
    Keywords: Fisheries ; Demersal fisheries ; Modelling ; Stocks ; Ecosystems ; Community fishing ; Inland waters ; Marine water ; Hydrologic cycle ; Fishermen ; Fishing fleet ; Shrimp fisheries ; Capture fisheries ; Fisheries management ; Trawling ; Artisanal fishing ; Fishing licenses
    Repository Name: AquaDocs
    Type: Theses and Dissertations , Bachelor thesis
    Format: 234
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  • 30
    Publication Date: 2021-05-19
    Description: Agriculture, Nature and Food Quality, Den Haag (Netherlands); Ministerie Van Buitenlandse Zaken, Brussel (Belgium); Wageningen International, Wageningen (Netherlands)
    Description: Projet BBI 13286 : Pêche durable des petits pélagiques en Afrique Nord Ouest Ce rapport a été préparé avec le soutien financier de la Coopération néerlandaise (DGIS) dans le cadre de son Programme de politique internationale en matière de biodiversité (BBI).
    Description: Published
    Description: pêche traditionnelle; taille; échantillonnage; écosystème; upwelling; biomasse; filet maillant dérivant; senne tournante; senne moustiquaire; senne de plage; maquereau; chinchard; sardinelle; ethmalose; reproduction; courant; stocks; réglementation; pêche par espéce; engin de pêche; pélagique; zone côtière; pirogue; pêche artisanale; pêcheur
    Keywords: Biomass ; Ecosystems ; Fisheries ; Fishermen ; Stocks ; Ocean currents ; Winds ; Size ; Fishing effort ; Pelagic fisheries ; Sexual reproduction ; Multispecies fisheries ; Fisheries ; Artisanal fishing ; Fishermen ; Fishing effort ; Canoe fisheries ; Coastal zone ; Fishery engineering ; Protected resources ; Pelagic fisheries ; Cycles ; Sexual reproduction ; Multispecies fisheries ; Stocks ; Ocean currents ; Winds ; Biomass ; Upwelling ; Ecosystems ; Maritime legislation ; Size
    Repository Name: AquaDocs
    Type: Report
    Format: 53
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  • 31
    Publication Date: 2021-05-19
    Description: Published
    Description: conservation
    Description: produits
    Description: pêche
    Keywords: Conservation ; Fisheries ; Fish products
    Repository Name: AquaDocs
    Type: Journal Contribution , Non-Refereed , Article
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  • 32
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    Nigerian Institute for Oceanography and Marine Research, | Lagos, Nigeria,
    Publication Date: 2021-01-30
    Description: Published
    Description: Fisheries newsletter
    Keywords: Fisheries ; Fisheries literature
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 8pp.
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  • 33
    Publication Date: 2021-01-30
    Description: En Afrique de l'Ouest, la zone littorale et ses ressources représentent une composante essentielle pour le développement. Près de 60% de la population est concentrée à moins de 20 km des côtes . La part des ressources halieutiques dans l'alimentation des populations est très importante et croissante. Au Sénégal par exemple, elles contribuent jusqu'à 70% des apports en protéines. A cela s'ajoute le poids socio-économique très important de la pêche en général et de la pêche artisanale en particulier devenue l'un des secteurs les plus stratégiques pour l'économie nationale en Mauritanie notamment. Le Cadre Stratégique de Lutte contre la Pauvreté du Gouvernement Mauritanien considère que : "compte tenu des possibilités qu'elle offre en terme de création d'emplois et de sécurité alimentaire notamment pour les populations pauvres, mais également de génération de recettes en devises, la pêche artisanale revêt une grande priorité, un plan décennal de développement lui sera consacré ".
    Description: Published
    Description: pêche artisanale; littoral; carpe; ethmalose; donnée; mulet; pélagique; pourtague; stock halieutique; pêche; communauté de pêcheurs; effort de pêche; PNBA; technique de pêche; senne tournante; sardinelle; gonade; filet de pêche; courbine; migration d'espèces; campagne de pêche; écosystème; dégradation d'habitats de poissons; enjeux socioéconomiques; commercialisation; conservation
    Keywords: Fisheries ; Fishermen ; Stocks ; Fish fillets ; Ecosystems ; Fishing effort ; Pelagic fisheries ; Artisanal fishing ; Fisheries ; Fishermen ; Stocks ; Capture fishery economics ; Fish eggs ; Fish fillets ; Fishing effort ; Fishery technology ; Mullet fisheries ; Pelagic fisheries ; Ecosystems
    Repository Name: AquaDocs
    Type: Report
    Format: 6
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  • 34
    Publication Date: 2022-05-25
    Description: Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of Taylor & Francis for personal use, not for redistribution. The definitive version was published in Aquaculture Economics & Management 16 (2012): 167-181, doi:10.1080/13657305.2012.678551.
    Description: This study presents a framework for analyzing the interactions between aquaculture and capture fisheries in the context of ecosystem-based management. We extend a model of the economic and ecological systems in coastal New England by incorporating an aquaculture sector in a computable general equilibrium (CGE) model and by examining the forage fish and aquaculture link in a marine food web. We show that aquaculture and commercial fisheries interact in a complex way throughout the economic and ecological systems.
    Description: This work was supported by the NOAA Saltonstall-Kennedy Grant Program (Award No. NA09NMF4270097), the MIT Sea Grant College Program (NOAA Award No. NA10OAR4170086, Subaward No. 5710002974), and the Johnson Endowment of the WHOI Marine Policy Center.
    Description: 2013-06-08
    Keywords: Aquaculture ; Fisheries ; Ecosystem-based management ; CGE model ; Food web model ; Forage fish
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
    Format: application/pdf
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  • 35
    Publication Date: 2022-05-25
    Description: Author Posting. © Ecological Society of America, 2013. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 23 (2013): 959–971, doi:10.1890/12-0447.1.
    Description: The biological benefits of marine reserves have garnered favor in the conservation community, but “no-take” reserve implementation is complicated by the economic interests of fishery stakeholders. There are now a number of studies examining the conditions under which marine reserves can provide both economic and ecological benefits. A potentially important reality of fishing that these studies overlook is that fishing can damage the habitat of the target stock. Here, we construct an equilibrium bioeconomic model that incorporates this habitat damage and show that the designation of marine reserves, coupled with the implementation of a tax on fishing effort, becomes both biologically and economically favorable as habitat sensitivity increases. We also study the effects of varied degrees of spatial control on fisheries management. Together, our results provide further evidence for the potential monetary and biological value of spatial management, and the possibility of a mutually beneficial resolution to the fisherman–conservationist marine reserve designation dilemma.
    Description: M. G. Neubert acknowledges the support of the National Science Foundation (DMS-0532378, OCE-1031256) and a Thomas B. Wheeler Award for Ocean Science and Society. H. V. Moeller acknowledges support from a National Science Foundation Graduate Research Fellowship. This research is based in part on work supported by Award No. USA 00002 made by King Abdullah University of Science and Technology (KAUST).
    Keywords: Bioeconomics ; Destructive fishing practices ; Fisheries ; Habitat damage ; Marine protected areas ; Marine reserves ; Optimal control ; Optimal harvesting ; Spatial management
    Repository Name: Woods Hole Open Access Server
    Type: Article
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  • 36
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    Ministerio de Medio Ambiente y Medio Rural y Marino | Madrid (Espagne)
    Publication Date: 2021-05-19
    Description: Description du secteur de la pêche Avec la Mauritanie, le Sénégal est de loin le plus grand producteur de produits de pêche de la sous région. Avec 718 km de cote et un territoire maritime de 198km2, 15 745 km2 de superficie fluviale, 2 estuaires, des mangroves et un lac de 350km2, le Sénégal possède tous les atouts des plus grands producteurs de pêche. Le potentiel annuel de captures s’élève à 500 000 tonnes. Le secteur a subi une croissance spectaculaire ces trente dernières années : les débarquements sont passés 50 000 tonnes en 1965 à plus de 450 000 en 1997. Le secteur se compose principalement de deux sous-secteurs : la pêche industrielle et la pêche traditionnelle ou artisanale. Cette dernière, vielle de plusieurs siècles a su s’adapter et se moderniser au cours des dernières décennies. La flotte de pêche artisanale est dynamique et diversifiée ; selon les estimations, en 2005 il y avait plus de 13 000 pirogues. La pêche artisanale se concentre dans sept régions maritimes et fluviales du pays: Dakar, Thiès, Saint Louis, Fatick, Zinguinchor, Louga et Kaolack. Le port de Kayar dans la région de Thiès correspond à la principale zone de débarquement de la pêche artisanale avec environ 70% des débarquements. Dans le secteur industriel, les pêcheurs travaillent à bord d’une flottille de petits sardiniers, de 143 chalutiers destinés à la pêche d’espèces demersales, de 3 sardiniers et de 42 thoniers. Alors que le Sénégal domine largement le sous-secteur demersale avec 70% des chalutiers opérants, le pays ne possède que 6 thoniers contre 38 étrangers, dont une partie seulement des captures est débarquée au Sénégal. La pêche industrielle est concentrée autour de la capitale dans le Port autonome de Dakar et des ports secondaires de Saint Louis, Kaolack et Ziguinchor. Aujourd’hui, le secteur de la pêche sénégalaise est largement dominé par la pêche artisanale, qui constituait 90% des cargaisons totales des produits de la mer en 2006 avec 350 000 tonnes. Plus de 60% des produits de la pêche artisanale sont destinés à l’exportation et la transformation. En 2006, le secteur dans son ensemble représentait 9% du PIB du secteur primaire, 1.5% du PIB total, et 1/3 des devises étrangères (250 millions de dollars par an). Plus importante que le poids économique du secteur, est son poids social : la pêche génère indirectement 600 000 emplois, dont 67% au sein du secteur artisanal. En outre, les produits de la pêche comblent les besoins en protéines animales de la population sénégalaise à hauteur de 75%1. La pêche a connu une expansion spectaculaire au cours des dernières décennies grâce à l’impulsion de politiques publiques de développement basées sur une logique sectorielle productiviste. Une flotte nationale artisanale et industrielle a été progressivement mise en place ainsi que de fortes capacités de transformation industrielle. Cet engagement de l’Etat a ensuite connu un net ralentissement du fait, entre autre, des politiques d’ajustement structurel. Le renchérissement des coûts de production subséquents à la dévaluation du franc CFA en 1994 a lourdement affecté les pêcheurs. Parallèlement, avec la forte demande en produits halieutiques et en l’absence de politiques adéquates et cohérentes de gestion durable des ressources exploitables, une situation de surexploitation des ressources halieutiques s’est installée. En conséquence de la raréfaction des ressources halieutiques, la pêche sénégalaise traverse une crise sans précédent, dont les effets commencent à se faire sentir à tous les niveaux : appauvrissement des communautés de pêcheurs, menace de l’approvisionnement en poisson des populations, baisse des captures à haute valeur ajoutée, baisse des exportations, baisse de la rentabilité et des revenus des unités de pêche. Par ailleurs, de plus en plus d’établissements de transformation industrielle ferment (23 entreprises entre 1999 et 2006).
    Description: Ministerio de Medio Ambiente Y Medio Rural y Marino
    Description: Pablo Manuel Xandri Royo CTP Proyecto (INT/07/16M/SPA) Este trabajo se ha realizado en el marco del Convenio de Colaboración entre el actual Ministerio de Medio Ambiente y Medio Rural y Marino de España y la Organización Internacional del Trabajo de 28 de diciembre de 2007
    Description: Published
    Description: environnement; socio-économie; pêche; capture; débarquement; engin de pêche; femme; pêcheur; convention internationale; réglementation
    Keywords: Fisheries ; Marine environment ; Socioeconomic aspects ; Capture fisheries ; Landing statistics ; Fishing gear ; Women ; Fishermen ; Conventions ; Fishery regulations
    Repository Name: AquaDocs
    Type: Report , Non-Refereed
    Format: 208
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  • 37
    Publication Date: 2021-05-19
    Description: Programme KURUKAN FUGAN (Union Européenne/Gouvernement du Sénégal/EndaGraf/GRET)
    Description: Published
    Description: politique de pêche; environnement marin; socio-économie; co-gestion; aquaculture; pêche artisanale; pêche industrielle; pêcherie; ONG; AMP; ressource halieutique; organisations professionnelles
    Keywords: Marine environment ; Socioeconomic aspects ; Fishery management ; Aquaculture ; Artisanal fishing ; Fisheries ; Industrial fish ; Fishery resources ; Fishing policy ; Protected areas ; Professionals
    Repository Name: AquaDocs
    Type: Book , Non-Refereed , Article
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  • 38
    Publication Date: 2021-01-30
    Description: Ministère des Affaires Etrangères (Sénégal); Ambassade du Sénégal à Rôme (Italy)
    Description: "Action 21"; FAO; application de l'accord; responsabilité de l'état du pavillon; échange d'informations; tiers à l'accord; règlement des différents; adhésion; entrée en vigueur; réserves; amendements; retraits; fonction du dépositaire.
    Keywords: Fisheries ; International agreements ; International cooperation ; Fisheries ; International agreements ; Maritime legislation ; International cooperation
    Repository Name: AquaDocs
    Type: Other
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  • 39
    Publication Date: 2021-09-18
    Description: En la época colonial algunas especies de peces cubanos retienen sus nombres por los cuales eran conocidos por los aborígenes: biajaca, biajaiba, cojinúa, jiguagua, cibí. Aún hoy se designan de igual forma. En esta época aparece la primera obra científica impresa en Cuba, los primeros pueblos pescadores y los primeros científicos.
    Description: Published
    Keywords: Fisheries
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  • 40
    Publication Date: 2021-09-18
    Description: Published
    Description: especies nativas
    Description: pesca
    Keywords: Fisheries ; Indigenous species ; Indigenous fishing
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    Publication Date: 2021-09-18
    Description: Published
    Keywords: Fisheries
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  • 42
    Publication Date: 2021-09-18
    Description: Recuento en forma breve de las pesquerías de estas especies durante varios siglos, en los cuales los sabios Parra y Felipe Poey ofrecen descripciones. Precios, lugares de captura y pescadores son los protagonistas.
    Description: Published
    Description: Emperador-Xiphias gladius
    Description: pez espada
    Description: castero-Makaira nigricans
    Description: aguja blanca-Tetrapturus albidus
    Keywords: Fisheries ; Fishes
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  • 43
    Publication Date: 2021-09-18
    Description: Causas del descenso en las pesquerías de estas especies a partir de 1975. Se describen las técnicas y artes de pesca empleadas y se abunda en la complejidad de las capturas y las características de los palangres empleados para cada especie. Una comparación es establecida además con países del área. De forma muy didáctica e instructiva.
    Description: Published
    Description: castero-Makaira nigricans
    Description: Emperador-Xiphias gladius
    Description: aguja blanca-Tetrapturus albidus
    Keywords: Fisheries ; Fishes
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  • 44
    Publication Date: 2022-05-26
    Description: Author Posting. © John Wiley & Sons, 2010. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Aquatic Conservation: Marine and Freshwater Ecosystems 21 (2011): 17-27, doi:10.1002/aqc.1158
    Description: 1. Interactions between cetaceans and fishing activity in the Archipelago of the Azores were examined using information contained in grey literature and previously unpublished data collected by observer programmes and research projects from 1998 to 2006. Together with a brief description of the economics, gear, fishing effort, and past and ongoing monitoring projects, levels of cetacean bycatch and interference were reported for each major fishery. 2. Cetaceans were present in 7% (n=973) and interfered in 3% (n=452) of the fishing events monitored by observers aboard tuna-fishing vessels. Interference resulted in a significantly higher proportion of events with zero catches but it was also associated with higher tuna catches. 3. There was a decreasing trend in the proportion of tuna-fishing events with cetacean presence or interference throughout this study, as well as a reduction in the estimates of dolphins captured annually by the whole fleet. 4. Observers reported cetacean depredation in 16% of the sets for demersal species and in 2% of the sets for swordfish. Cetacean presence and depredation were associated with higher overall catches and higher catches per unit effort in demersal fisheries. Bottlenose dolphins (Tursiops truncatus) were responsible for most depredation events in demersal fisheries, whereas in the swordfish fishery, depredation was associated with the presence of killer whales (Orcinus orca). There were no reports of cetacean bycatch in these fisheries. There were also no reports of cetaceans interacting in the experimental deep-sea fisheries that were examined. 5. Available data suggests that levels of interaction between cetaceans and Azorean fisheries are generally low and that the economic impact of cetacean interference is probably small. However, for several traditional fisheries there are no accurate data to determine levels of cetacean interaction. We recommend that existing observer programmes be expanded to increase observer coverage of the demersal and swordfish fisheries and allow monitoring of other existing and emerging fisheries.
    Description: M.A.S. was supported by an FCT postdoctoral (SFRH/BPD/29841/2006) grant, and R.P. was supported by an FCT doctoral grant (SFRH/BD/32520/2006).
    Keywords: Cetacean–fisheries interactions ; Depredation ; Bycatch ; Fisheries ; Atlantic Ocean ; Azores
    Repository Name: Woods Hole Open Access Server
    Type: Preprint
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  • 45
    Publication Date: 2022-05-26
    Description: Author Posting. © Inter-Research, 2006. This article is posted here by permission of Inter-Research for personal use, not for redistribution. The definitive version was published in Marine Ecology Progress Series 310 (2006): 263-270, doi:10.3354/meps310263.
    Description: The longfin squid Loligo pealeii is distributed widely in the NW Atlantic and is the target of a major fishery. A previous electrophoretic study of L. pealeii was unable to prove genetic differentiation, and the fishery has been managed as a single unit stock. We tested for population structure using 5 microsatellite loci. In early summer (June), when the squids had migrated inshore to spawn, we distinguished 4 genetically distinct stocks between Delaware and Cape Cod (ca. 490 km); a 5th genetic stock occurred in Nova Scotia and a 6th in the northern Gulf of Mexico. One of the summer inshore stocks did not show genetic differentiation from 2 of the winter offshore populations. We suggest that squids from summer locations overwinter in offshore canyons and that winter offshore fishing may affect multiple stocks of the inshore fishery. In spring, squids may segregate by genetic stock as they undertake their inshore migration, indicating an underlying mechanism of subpopulation recognition.
    Description: We acknowledge funding from WHOI Sea Grant NA16RG2273, the Massachusetts Environmental Trust (#98-04), and the Sholley Foundation.
    Keywords: Fisheries ; Spawning migration ; Microsatellites ; Population structure ; Population recognition ; Null alleles
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  • 46
    Publication Date: 2022-05-26
    Description: Author Posting. © Foundation for Environmental Conservation, 2009. This article is posted here by permission of Cambridge University Press for personal use, not for redistribution. The definitive version was published in Environmental Conservation 36 (2009): 268-276, doi:10.1017/S0376892910000032.
    Description: No-take marine reserves are widely recognized as an effective conservation tool for protecting marine resources. Despite considerable empirical evidence that abundance and biomass of fished species increase within marine reserve boundaries, the potential for reserves to provide fisheries and conservation benefits to adjacent waters remains heavily debated. This paper uses statistical and population models to evaluate published empirical data on adult spillover from marine reserves and shows that spillover is a common phenomenon for species that respond positively to reserve protection, but at relatively small scales, detectable on average up to 800 m from reserve boundaries. At these small scales, local fisheries around reserves were likely unsustainable in 12 of 14 cases without the reserve, and spillover partially or fully offsets losses in catch due to reserve closure in the other two cases. For reserves to play a role in sustaining and replenishing larger-scale fished stocks, networks of reserves may be necessary, but as few exist this is difficult to evaluate. The results suggest reserves can simultaneously meet conservation objectives and benefit local fisheries adjacent to their boundaries.
    Description: Support was provided by a grant from the David and Lucille Packard Foundation to NCEAS for ecosystem-based management ofmarine systems, the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) funded by the David and Lucile Packard Foundation and the Gordon and Betty Moore Foundation (contribution number 348), the Sustainable Fisheries Group supported by the Paul G. Allen Family Foundation and the Bahamas Biocomplexity Project (US NSF Biocomplexity grantOCE-0119976) andUS EPA Science to Achieve Results (R832223).
    Keywords: Adult fish movement ; Fisheries ; Global ; Marine protected areas ; No-take reserves ; Spillover effect ; Synthesis
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  • 47
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    Agriculture and human values 17 (2000), S. 125-139 
    ISSN: 1572-8366
    Keywords: Environment ; Fisheries ; Fordism ; Nation-State ; Regulation ; Supranational State ; Transnational corporations ; Transnational State
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract This analysis uses an analytical frameworkgrounded in political economy perspectives of theglobalization of the agro-food sector combined with acase study approach focusing on the Marine StewardshipCouncil (MSC) to inform discussions regarding thecharacteristics of societal regulation in thepost-Fordist era. More specifically, this analysisuses the case of the emergence of the MSC toinvestigate propositions regarding the existence of,and location of, nascent forms of a transnationalState. The MSC proposes to regulate the certificationof sustainable fisheries at the global level throughan eco-labeling program. The MSC was created in 1996by the transnational environmental organization theWorld Wildlife Fund and the transnational corporationUnilever. The emergence of the MSC has generatedheated discussion in fisheries management circles thatis in general divided along North/South lines. Thisanalysis indicates that the case of the MSC providesvaluable insights into the possible characteristics ofsupranational regulatory mechanisms that might emulatethe role of the nation-State in the post-Fordist era.
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  • 48
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    Springer
    Environment, development and sustainability 2 (2000), S. 277-304 
    ISSN: 1573-2975
    Keywords: Systems of Knowledge ; Local Knowledge ; Fisheries ; Resource Management
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Sociology
    Notes: Abstract During the last 20 years, the existence of rich systems of local knowledge, and their vital support to resource use and management regimes, has been demonstrated in a wide range of biological, physical and geographical domains, such as agriculture, animal husbandry, forestry and agroforestry, medicine, and marine science and fisheries. Local knowledge includes empirical and practical components that are fundamental to sustainable resource management. Among coastal-marine fishers, for example, regular catches and, often, long-term resource sustainment are ensured through the application of knowledge that encompasses empirical information on fish behaviour, marine physical environments, fish habitats and the interactions among ecosystem components, as well as complex fish taxonomies. Local knowledge is therefore an important cultural resource that guides and sustains the operation of customary management systems. The sets of rules that compose a fisheries management system derive directly from local concepts and knowledge of the resources on which the fishery is based. Beyond the practical and the empirical, it is essential to recognise the fundamental socio-cultural importance of local knowledge to any society. It is through knowledge transmission and socialisation that worldviews are constructed, social institutions perpetuated, customary practices established, and social roles defined. In this manner, local knowledge and its transmission, shape society and culture, and culture and society shape knowledge. Local knowledge is of great potential practical value. It can provide an important information base for local resources management, especially in the tropics, where conventionally-used data are usually scarce to non-existent, as well as providing a shortcut to pinpoint essential scientific research needs. To be useful for resources management, however, it must be systematically collected and scientifically verified, before being blended with complementary information derived from Western-based sciences. But local knowledge should not be looked on with only a short-term utilitarian eye. Arguments widely accepted for conserving biodiversity, for example, are also applicable to the intellectual cultural diversity encompassed in local knowledge systems: they should be conserved because their utility may only be revealed at some later date or owing to their intrinsic value as part of the world's global heritage. At least in cultures with a Western liberal tradition, more than lip-service is now being paid to alternative systems of knowledge. The denigration of alternative knowledge systems as backward, inefficient, inferior, and founded on myth and ignorance has recently begun to change. Many such practices are a logical, sophisticated and often still-evolving adaptation to risk, based on generations of empirical experience and arranged according to principles, philosophies and institutions that are radically different from those prevailing in Western scientific circles, and hence all-but incomprehensible to them. But steadfastly held prejudices remain powerful. In this presentation I describe the 'design principles' of local knowledge systems, with particular reference to coastal-marine fishing communities, and their social and practical usefulness. I then examine the economic, ideological and institutional factors that combine to perpetuate the marginalisation and neglect of local knowledge, and discuss some of the requirements for applying local knowledge in modern management.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 104-111 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Properties of FluoromethyldialkylaminesFluoromethyldialkylamines (3a-f) are prepared from N,N-acetals (aminals) by cleavage with carboxylic acid fluorides or l-fluoro-2,4-dinitrobenzene. They are low-boiling liquids and are characterized by a covalent carbon-halogen bond. Their reactivity is similar to that of the analogous carbimonium chlorides, bromides and iodides.
    Notes: Fluormethyl-dialkyl-amine (3a-f) werden durch Spaltung von Aminalen mit Carbonsäurefluoriden oder l-Fluor-2.4-dinitro-benzol gewonnen. Sie sind niedrigsiedende, durch eine kovalente Kohlenstoff-Halogen-Bindung charakterisierte Flüssigkeiten und zeigen ähnliche Reaktionsfähigkeit wie die analogen Carbimoniumchloride, -bromide oder -jodide.
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 133-146 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterosubstituted Fulvenes, IV In the 5-Membered Ring Unsubstituted 6,6-DiaminofulvenesAlkylation of tetrasubstituted thioureas with methyl iodide leads to S-methyl isothiuronium iodides 3, which have been transformed to 6,6-diaminofulvenes 1 by condensation with cyclopentadienyl sodium. Some compounds of type 1 are also obtainable from the reaction between cyclopentadiene and chloroformamidinium chlorides 4 in the presence of triethylamine. I.r., u.v., and n.m.r. spectra of 1 and 3 are discussed.
    Notes: Tetrasubstituierte Thioharnstoffe lassen sich mit Methyljodid in die S-Methyl-isothiuroniumjodide 3 überführen, die ihrerseits mit Cyclopentadienylnatrium die 6.6-Diamino-fulvene 1 bilden. Einzelne Vertreter von 1 sind auch aus Cyclopentadien und Chlorformamidinium-chloriden 4 in Gegenwart von Triäthylamin zugänglich. Die IR-, UV- und NMR-Spektren von 1 und 3 werden diskutiert.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 183-192 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: VinylsulfonylmethylidsThe preparation of dimethylsulfonio-(vinylsulfonylphenylsulfonylmethanide) (5), triphenyl-phosphonio-(vinylsulfonylphenylsulfonylmethanide) (6) and triphenylphosphonio-(vinyl-sulfonylbenzoylmethanide) (8) is described. The u. v. spectra of 5 and 6 are similar to the u.v. spectrum of the bis(phenylsulfonyl)methane anion (9). Because of the interaction of the SO2-groups with the ylide carbanions, the SO2-stretching frequencies compared to those of vinylsulfonylphenylsulfonylmethane (4) are shifted 20 -30/cm to lower wave numbers. This interaction causes a higher electron density in the vinyl groups of the ylids compared to 4, as shown by n. m. r. measurements. The mass spectra of 5, 6 and 8 are discussed.
    Notes: Die Synthese von Dimethylsulfonio-[vinylsulfonyl-phenylsulfonyl-methanid] (5), Triphenyl-phosphonio-[vinylsulfonyl-phenylsulfonyl-methanid] (6)undTriphenylphosphonio-[vinyl-sulfonyl-benzoyl-methanid] (8) wird beschrieben. Die Elektronenspektren von 5 und 6 sind mit dem UV-Spektrum des Bis-phenylsulfonyl-methan-Anions (9) vergleichbar. Durch Wechselwirkung der SO2Gruppen mit den Ylidcarbanionen werden die SO2-Valenzschwingungsfrequenzen im Vergleich zu Vinylsulfonyl-phenylsulfonyl-methan (4) um 20 - 30/cm zu kleineren Wellenzahlen verschoben. Diese Wechselwirkung bedingt eine höhere Elektronendichte in den Vinylgruppen der Ylide als bei 4, was NMR-spektroskopisch nachweisbar ist. Die Massenspektren von 5, 6 und 8 werden diskutiert.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 173-182 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Cyclopentadienones with Aliphatic Diazo Compounds, 6 Experiments with „Indanocyclone“„Indanocyclone“ 3, prepared from ninhydrin (1) and dibenzylketone (2), reacts with an ethereal diazomethane solution to form an 1 :1-adduct 4a and two isomeric 1 : 2-adducts, presumably 12 and 13. Elimination of N2 from 4a leads to the formation of the cyclopropane 7, the fluorenone 6 and, by way of phenyl migration, the new cyclone 8a; elimination of N2 from 12 and 13 leads to undefined products. 5 is converted via its hydrazone into the diazo compound 10. Ring enlargement of 6 with diazomethane produces the phenanthrene 9.Reaction of diazoethane with 3 gives the instable 1 :1-adduct 4b, which yields the new cyclone 8b by N2-elimination and phenyl migration. 8b also forms an 1 :1-adduct (11?). Phenyl diazomethane adds to 3 giving a rather stable 1 :1-adduct 14, the isomeric 16 and the epoxide 15. Elimination of N2 from 14 yields the fluorenone derivative 17, which upon treatment with excess diazomethane undergoes ring enlargement to form the phenanthrene derivative 18.
    Notes: Das aus Ninhydrin(l)und Dibenzylketon(2) erhältliche, Indanocyclon‘ 3 gibt mit ätherischer Diazomethanlösung ein 1 :1-Addukt 4a und zwei isomere 1 : 2-Addukte, vermutlich 12 und 13. 4a zerfällt unter N2-Abspaltung zum Cyclopropanderivat 7, zum Fluorenonderivat 6 und unter Phenylwanderung zum neuen Cyclon 8a; 12 und 13 geben bei der N2-Abspaltung keine definierten Produkte. Aus 5 wird über sein Hydrazon die Diazoverbindung 10 und mit Diazomethan unter Ringerweiterung das Phenanthrenderivat 9 erhalten.Mit Diazoäthan entsteht aus 3 das instabile I :1-Addukt 4b, das bei der N2-Abspaltung unter Phenylwanderung das Cyclon 8b bildet; dieses gibt erneut ein Diazoathan-Addukt (11?).Mit Phenyldiazomethan liefert 3 ein ziemlich stabiles 1 :1-Addukt 14 und sein Isomeres 16 sowie das Epoxid 15. Bei der N2-Abspaltung entsteht aus 14 das Fluorenonderivat 17, das mit Diazomethan zum Phenanthrenderivat 18 ringerweitert wird.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 222-235 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Orthoamides, X: Reaction of Vinylogous Amide Acetals, Aminalesters and Amide AminalsDerivates of vinylogous orthoformic acid amides react with Grignard compounds to give l,3-bis(dimethylamino)-l-alkenes (4-7), with methylene active compounds to give derivates of N.N-disubstituted 4-amino-l,3-butadienes (17  - 29) and with primary aromatic amines to form vinylogous, N,N,N′-trisubstituted amidines (31-36, 38-40).
    Notes: Vinyloge Orthoameisensäureamid-Derivate geben mit Grignard-Verbindungen 1.3-Bis - dimethylamino-alkene-(l) (4-7), mit methylenaktiven Verbindungen N.N-disubstituierte 4 - Amino-butadien-(l.3)-Derivate (17-29) und mit primären aromatischen Aminen vinyloge N.N.N′-trisubstituierte Amidine (31-36, 38-40).
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    Berichte der deutschen chemischen Gesellschaft 103 (1970) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 17-22 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Pyrimidines, VIII Synthesis and Properties of Uracil-4-carbaldehyde Hydrazone. The First Inner Orbital Complex of a Pyrimidine with CopperUracil-4-carbaldehyde (1) reacts with stoechiometric amounts of hydrazine to yield the azine 2. Under mild conditions (30 per cent hydrazine, room temperature) the azine is cleaved to uracil-4-carbaldehyde hydrazone (3). This cleavage by hydrazine is typical for the azomethine group in position 4 of the uracil ring. In aqueous or aqueous-alcoholic solution 3 reacts readily with aliphatic, aromatic and heterocyclic aldehydes to form mixed azines in good yield. With copper(II)-acetate 3 yields in aqueous solution a new type of symmetrical inner orbital complex in which the ratio of pyrimidine to copper is 2 :1. The crystalline and insoluble paramagnetic complex 13 presumably has a planar structure. Substitution of the amino group, even with a methyl group, prevents complex formation. 13 is decomposed by mineral acids to the respective copper salt and azine 2. In analogy to 1 2-thiouracil-4-carb-aldehyde forms the corresponding hydrazone 12.
    Notes: Uracil-carbaldehyd-(4) (1) liefert mit stöchiometrischer Menge Hydrazin das symmetrische Azin 2, welches unter milden Bedingungen (30proz. Hydrazin, Raumtemperatur) zum Uracil-carbaldehyd-(4)-hydrazon (3) gespalten wird. Die schonende Hydrazinolyse ist spezifisch für die Azomethingruppe in 4-Stellung des Uracilrings. 3 liefert in wäßriger bzw. Wäßrig-alkoholischer Lösung mit aliphatischen, aromatischen und heterocyclischen Aldehyden in guter Ausbeute gemischte Azine. Mit Kupfer(II)-acetat bildet 3 einen neuartigen symmetrischen Innerkomplex der Art Pyrimidin : Kupfer = 2:1. Analog zu Uracil-carb-aldehyd-(4) (1) erhält man aus 2-Thio-uracil-carbaldehyd-(4) mit Hydrazin das entsprechende Hydrazon 12.
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  • 56
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 46-49 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structure of l,2,3,4,4a,9a-hexahydro-4a,9-propanocarbazolium HydrobromideThe crystal structure of the title compound has been determined by X-ray structure analysis. From these results a twist angle of 64.5° of the orbital of the nitrogen is derived.
    Notes: Auf röntgenographischem Weg wurde die Kristallstruktur der Titel-Verbindung bestimmt. Aus den so erhaltenen Ergebnissen resultiert ein Verdrillungswinkel des Orbitals am Stickstoff von ϕpH = 64.5°.
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  • 57
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 76-81 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Enthalpy of Formation of Tungsten Hexafluoride and Tungsten PentafluorideThe heat evolved on combustion of tungsten and tungsten pentafluorid in fluorine was measured in a bomb calorimeter. The enthalpies of formation calculated from these values were found to be ΔH°298(WF6, g) = -411.7 ± 0.5 kcal mol-1 and ΔH°298 (WF5, c) -346.1 ± 2.6 kcal mol-1.
    Notes: Die Verbrennungswärmen von Wolfram und Wolframpentafluorid in Fluor wurden in einem Bombenkalorimeter gemessen. Die aus den Meßdaten errechneten Bildungsenthalpien betragen ΔH°298(WF6, gas) -411.7 ± 0.5 kcal Mol-1 und ΔH°298(WF5, fest) -346.1 ± +2.6-1.0 kcal Mol1.
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  • 58
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 97-103 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Inorganic Small Ring Compounds, III Cyclic Silyl-alkylidene PhosphoranesA simple method has been deviced for the synthesis of silyl-substituted alkylidene phosphoranes of the type F. Two members of this series, [(CH3)3PCSi(CH3)2]2 (1) and [( PCSi(CH3)2]2 (2), were prepared from methylene trimethyl and methylene tri-n-butyl phosphorane, resp., and dimethyl dichlorsilane and characterized by means of chemical analysis and n. m. r. spectroscopy. The pathway of the reactions is discussed and a possible mechanism confirmed by an independent preparation of the most likely intermediates. Among these the difunctional open-chain ylid 4, (CH3)3P= CH=Si(CH3)2=CH = P(CH3)3, is of special interest.
    Notes: Ein einfaches Darstellungsverfahren ermöglicht die Synthese von Silyl-alkylidenphosphoranen mit viergliedrigem Ringsystem des Typs F. Zwei Vertreter dieser Reihe, [(CH3)3PCSi(CH3)2]2 (1) und [(n-C4H9)3PCSi(CH3)2]2 (2), wurden aus Trimethyl-methylen- bzw. Tri-n-butyl-methylen-phosphoran und Dimethyldichlorsilan in guten Ausbeuten erstmals hergestellt und analytisch und NMR-spektroskopisch charakterisiert. Der Reaktionsablauf der Synthese wird diskutiert und durch die getrennte Darstellung möglicher Zwischenprodukte belegt. Unter letzteren ist das offenkettige difunktionelle Ylid 4, (CH3)3P=CH  -  Si(CH3)2  -  CH - P-(CH3)3, von Bedeutung.
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  • 59
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 147-155 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterosubstituted Fulvenes, V 6,6-Diaminofulvenes with Electronegative Substituents in the 5-Membered RingCondensation of tetramethyl chloroformamidinium chloride (5) with methoxycarbonyl-, bis(methoxycarbonyl)-, and cyanocyclopentadienyl salts leads to the correspondingly substituted 6,6-bis(dimethylamino)fulvenes 6, 7 and 8. Vilsmeier formylation of 6,6-bis(dimethyl-amino)fulvene yields the diformyl derivatives 9 and 11. Structure elucidation of the fulvenes obtained is based on spektroscopic data; the temperature dependence of the n.m.r. spectra is discussed.
    Notes: Tetramethyl-chlorformamidinium-chlorid (5) bildet mit Methoxycarbonyl-, Bis-methoxy-carbonyl- und Cyan-cyclopentadienylsalzen die im 5-Ring entsprechend substituierten 6.6-Bis-dimethylamino-fulvene 6, 7 und 8; Vilsmeier-Formylierung des 6.6-Bis-dimethylamino-fulvens liefert zwei Diformyl-Derivate 9 und 11. Die Strukturzuordnung der erhaltenen Fulvene erfolgt spektroskopisch; die Temperaturabhängigkeit der NMR-Spektren wird diskutiert.
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  • 60
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 205-209 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Compounds with Urotropin Structure, XLVI Synthesis of the 6-Thia-l,3-diazaadamantane Ring System.A synthesis of the hitherto unknown 6-thia-l,3-diazaadamantane ring system starting from N-benzenesulfonyl-diallylamine (1), is described. The first stage of the synthesis is the sulfurdichloride addition to 1, resulting in Nbenzenesulfonyl-2,6-bis(chloromethyl)thiomorpho-line (2).2 was converted with alkali into N-benzenesulfonyl-2,6-dimethylenethiomorpholine (6) and subsequently oxidized to the sulfone 7. Addition of benzylamine followed by removal of the benzyl and the benzenesulfonyl groups yielded 9-thia-3,7-diazabicyclo[3.3.l]nonane 9,9-dioxide (11), which reacted with formaldehyde to produce 6-thia-l,3-diazaadamantane 6,6-di-oxide (12).
    Notes: Ausgehend von Benzolsulfonsäure-diallylamid (1) wird das bisher noch unbekannte 6-Thia-1.3-diaza-adamantan-Ringsystem synthetisiert, wobei im ersten Schritt die Schwefeldichlorid-Addition an 1 zu 4-Benzolsulfonyl-2.6-bis-chlormethyl-thiomorpholin (2) erfolgt. 2 wurde mit Alkali in 4-Benzolsulfonyl-2.6-dimethylen-thiomorpholin (6) und durch anschließende Oxydation in das Sulfon 7 übergeführt. Benzylamin-Addition an 7 und anschließende Abspaltung des Benzyl- und Benzolsulfonyl-Restes führte zum 9-Thia-3.7-diaza-bicyclo[3.3.1]-nonan-9.9-dioxid (11), das mit Formaldehyd das 6-Thia-s-l.3-diaza-adamantan-6.6-dioxid (12) lieferte.
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  • 61
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    Keywords: Chemistry ; Inorganic Chemistry
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Orthoamides, XII: Synthesis of Acyl Isocyanate O,N- or -N,N-Acetals from Amide Acetals or from an Aminal tert-Butylester and N-Halogencarbonamides, Halogen Ureas and N-ChlorourethanesDimethylformamide dialkylacetals (2) and aminal-tert-butylester 5 [bis(dimethylamino)-tert-butoxymethane] react with N-halogen carboxylic acid amides, halogen ureas and N-chlorourethanes to give acyl isocyanate-O,N -or -N,N-acetals (isoureas 3 or guanidines 6, respectively).
    Notes: Dimethylformamid-dialkylacetale (2) und Aminal-tert.-butylester 5 (Bis-dimethylamino-tert.-butyloxy-methan) bilden mit N-Halogen-carbonsäureamiden, Halogenharnstoffen und N-Chlor-urethan Acylisocyanat-O.N- bzw. -N.N-acetale (Isoharnstoffe 3 bzw. Guanidine 6).
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  • 62
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 256-264 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Orthoamides, XIII Studies on the Mechanism of Electrophilic Substitution of the Formyl-H Atom in Ortho Formic Acid AmidesOrtho formic acid amides and N-halogen carboxylic acid amides, halogen ureas or N-chloro urethanes primarily react to give adducts; these form ylides in the presence of bases. The ylides react by an intramolecular SE1- or SNi-mechanism to give O,N-acetals of the corresponding acyl isocyanates (isoureas).
    Notes: Bei der Umsetzung von Orthoamiden mit N-Halogen-carbonsäureamiden, -harnstoffen und N-Chlor-urethan wurden Primär-Addukte nachgewiesen. Diese bilden in Gegenwart von Basen Ylide, welche über einen intramolekularen SE1- oder SNi-Mechanismus C-N-Knüpfung eingehen unter Bildung von O.N-Acetalen der entsprechenden Acylisocyanate (Isoharnstoffe).
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  • 63
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 281-288 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Boron Azides, X Aminoazidoboranes and AlkoxyazidoboranesThe bis(dialkylamino)azidoboranes l a and 1b, the dialkylaminodiazidoboranes 2a and 2 b, diethylaminoazidophenylborane (3), and the dialkoxyazidoboranes 4 a and 4 b are formed from chloroboranes, chlorine being substituted by the N3-group with LiN3 or Bu3SiN3, respectively, as substitution agents. The monoazidoboranes 1, 3, and 4 are decomposed in a kinetically controlled manner at a noticeable rate only beyond 250° C; hydrolysis of the polymeric material gives the amines Et2NNH2 (from 1b), PhNH2 (from 3) and CH3ONH2 (from 4 a), respectively, indicating a rearrangement process during the thermolysis. The saltlike compounds (NH4N4 and (Et2NH2)N3, respectively, are the main products from the decomposition of the diazidoboranes 2a and 2b at 210°. The thermal decomposition of la in cyclohexene yields under participation of the solvent the diazadiborete derivative 6. From the photolytic decomposition of 1a and 1b, respectively, trisaminoboranes (as dismutation products) and the tetraaminodiazadiboretes 10 a and 10 b (as rearrangement products) are isolated.
    Notes: Die Bis(dialkylamino)azidoborane l a und l b, die Dialkylaminodiazidoborane 2 a und 2 b, Diäthylaminoazidophenylboran (3) und die Dialkoxyazidoborane 4 a und 4 b erhält man aus den entsprechenden Chlorboranen durch Azidierung mit LiN3 bzw. (im Falle von 4a) mit Bu3SiN3. Die Monoazidoborane 1, 3 und 4 zerfallen in kinetisch kontrollierbarer Weise mit nennenswerter Geschwindigkeit erst oberhalb 250°; neben N2 erhält man harzige Produkte, aus denen sich durch Verseifung die aus einer Umlagerungsreaktion hervorgegangenen Amine Ät2NNH2 (aus l b), PhNH2 (aus 3) bzw. CH3ONH2 (aus 4a) freimachen lassen. Der thermische Zerfall der Diazidoborane 2a und 2b bei 210° liefert neben N2 die salzartigen Azide (NH4)N3 bzw. (Nät2H2)N3. Der thermische Zerfall von l a in Cyclohexen führt unter Beteiligung des Lösungsmittels zum Diazadiboret-Derivat 6. Tetraaminodiazadiborete 10 a und 10 b sind neben Trisaminoboranen die Hauptprodukte des photolytischen Zerfalls von l a und l b.
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    Keywords: Chemistry ; Inorganic Chemistry
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    Topics: Chemistry and Pharmacology
    Notes: Wir berichteten vor einiger Zeit über die Pyrolyse von Silbertetrafluorphthalat (1) und äußerten die Vermutung, daß als Hauptprodukt isolierte Octafluorbiphenylen seine Bildung dem intermediären Auftreten des Tetrafluorbenz-ins verdankte. Um diese Vermutung zu bestätigen, wurde die Pyrolyse von 1 in Gegenwart eines potentiellen Benz-in-Abfängers durchgeführt. In Anlehnung an McNelis setzten wir dafür Tetraphenylcyclopentadienon (Tetracyclon) (2) ein.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 322-324 
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    Keywords: Chemistry ; Inorganic Chemistry
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    Topics: Chemistry and Pharmacology
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 788-798 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Method for Synthesis of Peptides: Activation of the Carboxyl Group with Dicyclohexylcarbodiimide using 1-hydroxybenzotriazoles as Additives1-Hydroxybenzotriazole and a number of substituted 1-Hydroxybenzotriazoles are suitable additives in the synthesis of peptides using the dicyclohexylcarbodiimide method1). The glc-racemisation test described by Weygand and coworkers2) was used to determine the influence of these additives on the racemisation during peptide synthesis. The newly employed additives decrease racemisation, prohibit the formation of N-acylurea and afford peptides in excellent yield and a high state of purity.
    Notes: 1-Hydroxy-benzotriazol sowie verschiedene kernsubstituierte 1-Hydroxy-benzotriazole eignen sich als Zusätze bei der Dicyclohexylcarbodiimid-Methode zur Synthese von Peptiden. Ihr Einfluß auf die Racemisierung bei Peptidsynthesen wurde unter Anwendung des gaschromatographischen Racemisierungstests von Weygand u. Mitarbb.2) untersucht. Die neuen Zusätze senken die Racemisierung, verhindern die N-Acyl-harnstoffbildung und führen in hoher Ausbeute zu sehr reinen Peptiden.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 426-439 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Stereochemistry of Sigmatropic 1,5-Hydrogen ShiftsAt 250° (S)-cis,trans-3-methyl-7-deutero-octa-4,6-diene (5) rearranges by a non-catalysed first order reaction to a mixture of (R)-trans,cis-3-methyl-7-deutero-octa-3,5-diene (3) and (S)-cis,cis-3-methyl-7-deutero-octa-3,5-diene (4). Therefore the sigmatropic 1,5-hydrogen shift proceeds in this system preferentially by way of a suprafacial transition state, which is at least 8 kcal/mol lower in energy than the antarafacial one.
    Notes: (S)-cis,trans-3-Methyl-7-deutero-octadien-(4.6) (5) lagert sich bei 250° in einer nichtkatalysierten Reaktion erster Ordnung in ein Gemisch aus (R)-trans,cis-3-Methyl-7-deutero-octadien-(3.5) (3) und (S)-cis,cis-3-Methyl-7-deutero-octadien-(3.5) (4) um. In diesem System durchläuft die sigmatrope 1.5-Wasserstoffverschiebung damit bevorzugt einen suprafacialen Übergangszustand, der um mindestens 8 kcal/Mol gegenüber dem antarafacialen Übergangszustand begünstigt ist.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 855-862 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Catalytic Hydroalumination of 1,5-HexadieneThe hydroalumination of 1,5-hexadiene normally yields (cyclopentylmethyl)dialkylaluminium instead of the expected dimetallated hexane derivative. Titanium tetrabutoxide catalyses the reaction and favours the formation of the dimetallated product. - When the reaction is carried out in the absence of a catalyst but in the presence of electron donors such as ethers or tertiary amines, the two-fold hydroaluminated product is also formed exclusively. In such cases the reaction velocity is, however, drastically reduced. Titanium tetrabutoxide has now been found to act as an extraordinarily effective catalyst for this reaction, even in the presence of complex-forming agents. Certain amines or tetrahydrothiophene even intensify the catalytic activity of the titanium (IV) compound.
    Notes: Die Hydroaluminierung von Hexadien-(1.5) führt normalerweise nicht zu dem erwarteten dimetallierten Hexanderivat, sondern zum Cyclopentylmethyl-dialkyl-aluminium. Titantetrabutylat katalysiert die Reaktion und lenkt sie in Richtung des dimetallierten Produktes. Bei Durchführung der Reaktion ohne Katalysator, jedoch in Gegenwart von Elektronendonatoren wie Äthern oder tertiären Aminen wird ebenfalls ausschließlich das zweifach hydroaluminierte Reaktionsprodukt gebildet. Die Reaktionsgeschwindigkeit wird dabei allerdings drastisch vermindert. Titantetrabutylat katalysiert nun die Reaktion auch bei Anwesenheit der Komplexbildner außerordentlich wirksam. Durch einige tertiäre Amine oder auch durch Tetrahydrothiophen wird die katalytische Aktivität der Titan (IV)-Verbindung sogar noch verstärkt.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 486-495 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydrazine Reactions, X Studies on Inversion-isomeric 1-Chloro-and 1-Aminoaziridines. Dependence of the 1H-C-14N-Coupling on the Konformation of the free Electron PairThe 1H-C-14N coupling depends on the conformation of the nitrogen lone-pair electrons. In 1-chloroaziridine for protons „cis“ to the nitrogen lone-pair electrons great values were found and for „trans“ protons smaller ones. The AA' BB'-system in the n.m.r. spectrum of 1-chloroaziridine is unsymmetrical. Irradiating of 14N frequency gives decoupling of 14N from other nuclei and the spectrum becomes symmetrical. In 1-amino-2-phenylaziridine the isomer with phenyl and amino group in „trans“ position is favoured. The variation of chemical shift in benzene solution of 1-amino- and 1-chloroaziridines are discussed.
    Notes: Die 1H-C-14N-Kopplung ist von der Konformation des freien Elektronenpaares abhängig und besitzt im 1-Chlor-aziridin für zum freien Elektronenpaar„cis“-ständige Protonen große, für „trans“-ständige kleine Werte. Das AA' BB'-System des NMR-Spektrums von 1-Chloraziridin ist daher unsymmetrisch und zeigt erst beim Einstrahlen der 14N-Frequenz infolge Spinentkopplung Symmetrie. 1-Amino-2-phenyl-aziridin liegt bevorzugt als das Inversionsisomere vor, in dem Phenyl- und Aminogruppe „trans“ zueinander stehen. Die Signalverschiebungen von 1-Amino-und 1-Chlor-aziridinen in Benzol werden diskutiert.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 534-538 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Structure of SphaerophysineSphaerophysine-formerly described as 1 or 2- is shown by n.m.r. and mass spectrometry to have structure 3 (N-(4-aminobutyl)-N-(3-methyl-2-butenyl)-guanidine). Dihydro-3 (7) has been synthesised.
    Notes: Sphaerophysin wurde bisher als 1-Isopentenylamino-4-guanidino-butan 1 oder 2 angesehen. Wir zeigen anhand von NMR- und Massenspektren sowie durch Synthese der Dihydro-verbindung, daß es die Struktur 3 eines N[4-Amino-butyl]-N-[3-methyl-buten-(2)-yl]-guanidins hat.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 564-572 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterosubstituted Acetylenes, XXV Chain-Extension of Aldehydes and Ketones by two Carbon Atoms with Ynamines: Synthesis of Substituted AcrylamidesThe addition of ynamines to carbonyl groups, especially of aldehydes and ketones, leads to derivatives of acrylamides by reduction of which with lithiumaluminiumhydride and hydrogenation amines are available. The stereochemistry of the condensation has been investigated. cis- acrylamides are stereospecifically obtained by a kinetically controlled reaction from aldehydes.
    Notes: Die Addition von Inaminen an Carbonylverbindungen, insbesondere Aldehyde und Ketone. Führt zu Acrylamidderivaten, aus denen mit Lithiumaluminiumhydrid und durch Hydrierung Amine erhältlich sind. Die Stereochemie der Addition wurde untersucht: Aus Aldehyden entsteht kinetisch gesteuert und stereospezifisch das cis-Acrylamid.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 648-651 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 659-662 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polycyclic Hydrocarbons by Cycli-alkylation, IV. Cycli-alkylations of Benzene and Partially Hydrogenated Polycyclic Aromatic Hydrocarbons with 1.2-Bis(bromomethyl)cyclohexaneThe reactions of benzene and partially hydrogenated aromatic hydrocarbons such as tetrahydronaphthalene and symm. octahydrophenanthrene with a mixture of cis- and trans 1.2-Bis (bromomethyl)cyclohexane in the presence of aluminiumchloride lead to the partially hydrogenated polycyclic hydrocarbons 2-6; the dehydrogenation with Pd/C yields the corresponding aromatic compounds.
    Notes: Die Reaktionen von Benzol and teilhydrierten Aromaten, wie Tetrahydronaphthalin und symm. Octahydrophenanthren, mit einem Gemisch aus cis- und trans-1.2-Bis-brommethyl-cyclohexan in Gegenwart von Aluminiumchlorid führen zu den partiell hydrierten polycyclischen Kohlenwasserstoffen 2-6, deren Dehydrierung mit Pd/C die entsprechenden Aromaten ergibt.
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  • 74
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 685-693 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Alkylidenetriphenylphosphoranes, XXV. A New Synthesis of α.β-Unsaturated Carboxylic AcidsThe reaction between alkylidenetriphenylphosphoranes (1) and α-bromo-or α-iodocarboxylic esters (2) (ratio 2:1) gives rise to the formation of α,β-unsaturated carboxylic esters (4), triphenylphosphine and phosphonium salts. The mechanism and the sterochemistry of this reaction are discussed.
    Notes: Triphenylphosphinalkylene (1) reagieren mit α-Brom-oder α-Jod-carbonsäureestern (2) im Molverhältnis 2:1 zu α.β-ungesättigten Carbonsäureestern (4), Triphenylphosphin und Phosphoniumsalzen. Der Mechanismus und die Stereochemie dieser Reaktion werden diskutiert.
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  • 75
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1463-1476 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Rearrangement Reactions, V. A Kinetic Study on the Mechanism of the Wolff-RearrangementFor the thermal Wolff-rearrangement in the presence of nucleophiles such as alcohols or amines, the nitrogen evolution is measured as a function of the nucleophile concentration. With triphenylacetyldiazomethane and diacyldiazomethanes no influence of benzyl alcohol or aniline on the decomposition constants was found, whereas with phenylbenzoyldiazomethane, 2-oxo-1-diazocyclohexane and -dodecane a linear increase with the nucleophile concentration is observed. Benzyl alcohol, aniline and N-methylaniline are more active than pyridine, benzylamine or polar compounds such as nitrobenzene or bromobenzene. This acceleration is evidently a consequence of proton activity of the nucleophiles and not of an addition according to 2 → 3. The same effect is also observed with diazo compounds which cannot undergo the Wolff-rearrangement.
    Notes: Für die thermische Wolff-Umlagerung in Gegenwart von Nucleophilen (Alkohole, Amine) wird die Geschwindigkeit der Stickstoffentwicklung in Abhängigkeit von der Nucleophil-Konzentration gemessen. Bei Triphenylacetyl-diazomethan (7) sowie Diacyl-diazomethanen wird kein Einfluß von Benzylalkohol oder Anilin auf die Zersetzungskonstanten beobachtet, bei Phenyl-benzoyl-diazomethan, 2-Oxo-1-diazo-cyclohexan und -dodecan dagegen ein linearer Anstieg mit der Nucleophil-Konzentration. Benzylalkohol, Anilin und N-Methyl-anilin sind wirksamer als Pyridin, Benzylamin oder rein polare Zusätze wie Nitro- und Brombenzol. Diese Beschleunigung ist offenbar eine Folge der Protonaktivität der Nucleophile und nicht einer Einlagerung gemäß 2 → 3. Sie tritt auch bei Diazoverbindungen auf, die zur Wolff-Umlagerung nicht befähigt sind.
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  • 76
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1512-1521 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Aromatic Erythrina-Alkaloids, XIII. A Direct Course to cis-15,16-Dimethoxyerythrinane-1,8-dioneThe enollactam 5 is obtained from ethyl dihydroresorcinol-2-acetate via the diketalamide 16. Cyclisation by heating with phosphoric acid yields the ketolactam 6; the overall yield of the five steps synthesis is 20%.
    Notes: Aus Dihydroresorcin-2-essigester wird über das Diketalamid 16 die Cyclisierungsvorstufe 5 gewonnen. Sie liefert beim Erhitzen mit Phosphorsäure das Ketolactam 6 mit einer Ausbeute von 20% über 5 Stufen.
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  • 77
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1168-1173 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Arylidene Isophorones Preparation and Properties of a Halochromic Polymethine SystemIsophorone (1) and araldehydes condense to give aryliden-isophorones 2-19. The yellow ary-dien-one systems of 2-19 form red polymethine cations like 21. Compounds of vinylogous carbonic acid structure yield red polymethine anions like 22. Differences between cation and anion are spectroscopically small with 6 relative to benzaurin (20).
    Notes: Aus Isophoron (1) und Araldehyden erhält man die Arylidenisophorone 2-19. Das gelbe Aryl-dien-on-System in 2-19 addiert leicht Protonen zu roten Polymethin-Kationen wie 21; vinyloge Carbonsäuren wie 6 bilden durch Dissoziation rote Polymethin-Anionen (22).Kation und Anion von z. B. 6 sind einander spektroskopisch ähnlicher als die analogen Salze des Benzaurins (20).
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1216-1224 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterosubstituted Acetylenes, XXX1). A new Mechanism of Nucleophilic Halogen Substitution at Acetylene Triple BondsThe combination of nucleophilic and directiospecific addition in β-position to halogen 1) (except fluorine) with subsequent onium rearrangement is proposed as a new mechanism of nucleophilic halogen substitution at the acetylene triple bond. The reactions of chloro-tertbutyl-acetylene (1) with phenolate and thiophenolate are described as examples. The β-adducts 2,5 und 6 are formed directiospecifically. 5 and 6 give rise photochemically and thermally to the thermodynamically more stable isomer 8 in which the chlorine atom and the thioether residue have migrated and changed their C-atoms. All thioether isomers produce the tert-butylethinyl-thioether 10 upon elimination of HCl.
    Notes: Die Kombination von nucleophiler directiospezifischer Addition in β-Stellung zum Halogen1) (außer Fluor) mit anschließender Onium-Umlagerung 2) und Halogen-Anion-α-Eliminierung wird als neuer Mechanismus der nucleophilen Halogensubstitution an der Acetylendreifachbindung vorgeschlagen. Als Beispiel für diese Reaktionsschritte werden die Umsetzungen von Chlor-tert.-butyl-acetylen (1) mit Phenolat und mit Thiophenolat beschrieben. Directiospezifisch entstehen die β-Addukte 2,5 und 6. Thermisch und photochemisch bildet sich aus 5 und 6 das thermodynamisch stabilere Isomere 8, in welchem Chlor und der Thioätherrest unter Vertauschung der C-Atome gewandert sind. Alle Thioäther-Isomeren liefern bei der HCl-Abspaltung den tert.-Butyläthiny-thioäther 10.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1273-1278 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition Metal Carbene Complexes, XIX. Synthesis of Cyclopropane Derivatives with Transition Metal Carbonyl Carbene ComplexesPhenyllmethoxycarbenepentacarbonylchromium(0) (1b) reacts on warming with trans-methyl crotonate (2) stereospecifically to give the isomeric methyl 2-methoxy-3-methyl-2-phenycyclopropane-1-carboxylates (3a, b) via transfer of the carbene ligand. The configuration of the isomers was determined by analysis of the 1H n.m.r. spectra.
    Notes: Phenylmethoxycarben-pentacarbonyl-chrom(0) (1b) reagiert bei erhöhter Temperatur unter Übertragung des Carbenrestes mit trans- Crotonsäure-methylester (2) stereospezifisch zu den isomeren 2-Methoxy-3-methyl-2-phenyl-cyclopropan-carbonsäure-(1)-methylestern (3a, b). Die Konfiguration der Isomeren wurde durch Analyse der 1H-NMR-Spektren bestimmt.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1306-1306 
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    Keywords: Chemistry ; Inorganic Chemistry
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    Topics: Chemistry and Pharmacology
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  • 81
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    Berichte der deutschen chemischen Gesellschaft 103 (1970) 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1334-1346 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photochemistry of Small Rings, 19. Photolysis of Spiro-pyrazoles to Cyclopropabenzenes and their ReactionsPhotolysis of cyclopentadiene-spiro-pyrazoles (9) in benzene yields 1 H-cyclopropabenzenes (10) in a novel reaction. The latter compounds can be rearranged thermally to benzofuranes (11). Degradation reactions of diphenylcyclopropabenzene 10c to give 2′-p-terphenylylacetic acid (14c) together with the spectroscopic data prove the structure of the cyclopropabenzenes.  -  The formation of 10 from 9 involves n→π*-excitation, followed by ring enlargement to indazoles (24) which eliminate nitrogen in a familiar manner. The excited states of 9 and 24 are triplets.
    Notes: Die Photolyse von Cyclopentadien-spiro-pyrazolen (9) in Benzol liefert in einer neuartigen Reaktion 1 H-Cyclopropabenzole (10). Diese können thermisch in Benzofurane (11) umgelagert werden. Abbaureaktionen des Diphenyl-cyclopropabenzols 10c zu p-Terphenylyl-(2′)-essigsäure (14c) zusammen mit den spektroskopischen Daten beweisen die Struktur der Bicyclen 10.  -  Die Bildung von 10 aus 9 verläuft über eine n→π*-Anregung, gefolgt von einer Ringerweiterung zu Indazolen (24), die in bekannter Weise Stickstoff eliminieren. Die Anregungszustände von 9 und 24 sind Tripletts.
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    Description / Table of Contents: Reactions of Short-Life Radicals, VII. The Stereochemical Route of Free-Radical Additions to Conjugated Dienes: Hydrostannation and Isomerization of Penta-1,3-dieneThe radical addition of Me3SnH and Et3SnH to both of the pure stereoisomers of penta-1,3-diene proceeds by a highly stereospecific mechanism, whereby an extremely high configurational stability of the intermediate allyl radicals 9 is indicated. Besides 1,2- and 1,4-adducts small amounts of 4,1-adducts are formed: altogether 6 of the 8 possible isomers 1-8 are obtained. At 80° the cis-diene reacts 2.6 or 2.9 times faster than the trans-isomer. At 20° and 40° only the transoid conformation is involved in the reaction of cis-isomer, whereas in the case of the trans-diene both cisoid and transoid configurations are involved. The attack of organotin radicals at C-4 (that is, at the internal C=C double bond) is much more readily reversible than that at C-l and leads (primarily) to cis-trans-isomerization of the diene; this is highly dependent on the molar ratio of diene to hydride. By means of capillary gas chromatography it was possible to observe each stage of the addition and isomerization processes.
    Notes: Die beiden Stereoisomeren von Pentadien-(1.3) addieren (CH3)3SnH und (C2H5)3SnH radikalisch hochgradig stereospezifisch, woraus eine beträchtliche Konfigurationsstabilität der intermediär auftretenden Allylradikale 9 folgt. Neben 1.2- und 1.4- entstehen wenig 4.1-Addukte, insgesamt 6 der 8 möglichen Isomeren 1-8. Das cis-Dien reagiert bei 80° 2.6 bzw. 2.9 mal schneller als das trans-Isomere. Bei 20° und 40° ist nur die transoide Konformation des cis-Isomeren beteiligt, beim trans-Dien dagegen sowohl cisoide als auch transoide. Der Angriff von Stannylradikalen an C-4, also an der mittelständigen C=C-Gruppe, ist weit stärker reversibel als derjenige am endständigen C-l und bedingt so (hauptsächlich) eine cis-trans-Isomerisierung des Diens. Diese hängt stark vom Molverhältnis Dien : Hydrid ab. Mittels Kapillar-GC konnten Additionen und Isomerisierung in jedem Stadium verfolgt werden.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1412-1419 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Identification and Preparation of Metalated NitroarenesPhenyllithium is unable to metalate nitrobenzene in THF, but instead is oxidized quantitatively to phenol at low temperatures. With 2-bromo-1-nitrobenzene and its methyl homologues a bromo-lithium exchange is effected to give high yields of the deeply coloured title compounds. They are stable only below -100° and are trapped as carboxylic acids with carbon dioxide. The halogen-metal exchange competes with the reduction of the nitro group, the latter reaction being favoured at higher temperatures and in solvents of low polarity. The redox reactions at the nitro group predominate with 3-and 4-bromo-1-nitrobenzene even under optimum conditions.
    Notes: Nitrobenzol wird durch Lithiumorganyle nicht metalliert. Dagegen oxydiert es Phenyllithium in Tetrahydrofuran(THF) schon bei tiefer Temperatur quantitativ zu Phenol. Der Brom-Lithium-Austausch an 2-Brom-1-intro-benzol und seinen Methylhomologen führt in hohen Ausbeuten zu den unterhalb von -100° stabilen, tieffarbigen Titelverbindungen, die man durch Carboxylierung nachweist. Die mit dem Halogen-Metall-Austausch konkurrierende Reduktion der Nitrogruppe tritt bei höherer Temperatur und in weniger polaren Lösungsmitteln stärker hervor; sie überwiegt bei 3- und 4-Brom-1-nitro-benzol auch unter optimalen Bedingungen.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1477-1485 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Diazo Compounds, VII. Comparative Kinetic Investigations on the Thermal Stability of Aliphatic Diazo CompoundsThe thermal stabilities of 16 aryl-, carbonyl-, sulfonyl-, phosphinyl- and phosphono-substituted diazomethanes are compared. From kinetic measurements on the decomposition of the diazo compounds in mesitylene the comparison values τ100, T 0.1 and k100 as well as the activation energy Ea of the N2-elimination were determined (see table 1). The following series of substituents with increasing stabilizing effect was derived:C6H5 〈 C6H5CO 〈 CH3CO 〈 Aryl-SO2 〈 (C6H5)2PO 〈 C2H5OCO 〈 (C2H5O)2PO 〈 H Carbonyl diazo compounds are thermally less stable than their PO-analogs (see figure 1), because of the mesomerism C ↔ D resulting from the interaction of the CO- and CN2-groups.
    Notes: Die thermischen Stabilitäten von 16 aryl-, carbonyl-, sulfonyl-, phosphinyl- und phosphono-substituierten Diazomethanen werden verglichen. Aus der Zersetzungskinetik in Mesitylen werden die Vergleichsgrößen τ100, T0.1 bzw. k100 sowie die Aktivierungsenergie Ea der N2-Abspaltung bestimmt. (s. Tab. 1). Eine Stabilisierungsreihe für die folgenden Substituenten wird abgeleitet: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 6} {\rm h}_{\rm 5} {\rm 〈 C}_{\rm 6} {\rm H}_{\rm 5}{\rm CO 〈 CH}_{\rm 3} {\rm CO 〈 Aryl - SO}_{\rm 2} {\rm 〈 (C}_{\rm 6} {\rm H}_{\rm 5} {\rm)}_{\rm 2} {\rm PO 〈 C}_{\rm 2} {\rm H}_{\rm 5} {\rm OCO 〈 (C}_{\rm 2} {\rm H}_{\rm 5} {\rm O)}_{\rm 2} {\rm PO 〈 H} $$\end{document}Carbonyl-diazoverbindungen sind thermisch instabiler als ihre PO-Analogen (s. Abbild.), bedingt durch mesomere Wechselwirkungen zwischen CO- und CN2-Gruppe gemäß C↔D.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1522-1535 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Aromatic Erythrina-Alkaloids, XIV. Application of the Glyoxylester Synthesis to DihydroresorcinolThe monocycloketal 7 of dihydroresorcinol yields, via glyoxylester synthesis, the condensation product 10. On treatment with dilute phosphoric acid, 10 hydrolyses to give the partially hydrogenated ketoisatin derivative 14a which is stabilised by conjugation and cannot be cyclised. In the presence of crystalline phosphoric acid 10 forms a violet cation, Pictet-Spengler cyclisation of which leads to a mixture of stereoisomeric spiroisoquinolines (22). From the mixture two racemates are isolated, the n. m. r. analysis of which permits the assignment of cis- and trans-configurations according to the formulae 22A and 22B.
    Notes: Aus dem Monocycloketal 7 des Dihydroresorcins wird auf dem Weg der Glyoxylestersynthese die Cyclisierungsvorstufe 10 gewonnen. Sie hydrolysiert unter der Einwirkung von verdünnter phosphorsäure zu dem Partiell hydrierten Ketoisatin-Derivat 14a, das durch Konjugation stabilisiert und nicht cyclisierbar ist. Mit kristalliner Phosphorsäure entsteht aus 10 ein violettes Kation, das durch Ringschluß nach Pictet-Spengler zu einem Gemisch stereoisomerer Spiroisochinoline 22 abreagiert. Nach Auftrennung in zwei Racemate wird durch NMR-Analyse die sterische Zuordnung zur cis- und trans-Reihe entsprechend den Formulierungen 22A und 22B ermittelt.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1572-1577 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of 2,2′-Bisoxazolyls and 2,2′ -Bisthiazolyls, of Arylene-bis-2-oxazolyl and Arylenebis-2-thiazolyl DerivativesThe reaction of desylamine hydrochloride with carboxylic acid chlorides and dicarboxylic acid chlorides yields ms- (acylamino) desoxybezoins (2a, b) and amides of N, N′ -bis-desyldicarboxylic acids (2c,-f), respectively. These compounds are converted by condensation with phosphorus pentachloride to derivatives of oxazole (3) and by condensation with phosphorus pentasulfide to derivatives of thaizole(4).
    Notes: Durch Umsetzung von Desylaminhydrochlorid mit Carbonsäurechloriden bzw. mit Dicarbonsäuredichloriden gelangt man zu ms-Acyalmino -desoxybenzoinen (2a, b) bzw. zu N. N′-Bis-desyl- dicarbonsäurediamiden (2c-f). Diese lassen sich mit Phosphorpentachlorid zu Oxazolderivaten 3, mit Phosphorpentasulfid zu Thiazolderivaten 4 kondensieren.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1631-1636 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Monosaccharides Containing Nitrogen in the Ring, XXVIII. Synthesis and Dimerization of 5-Benzylamino-1,2-O-isopropylidene-5-deoxy-L-ido-hexodialdo-1,4(β)-3,6(α,β)-difuranoseSelective hemihydrogenation of 5-benzylamino-1,2-O-isopropylidene-5-deoxy-β-L-idofuranuronic acid nitrile (1) yields 5-benzylamino-1,2-O-isopropylidene-5-deoxy-L-ido-hexodialdo-1,4(β)-3,6(α,β)-difuranose (2), which can be dimerized to 5. 5 represents a symmetrical heptacyclic system of five- and six-membered rings containing a central piperazine ring.
    Notes: Selektive Halbhydrierung des 5-Benzylamino-1.2-O-isopropyliden-5-desoxy-β-L-idofuranuron-säurenitrils (1) liefert 5-Benzylamino-1.2-O-isopropyliden-5-desoxy-L-ido-hexodialdo-1.4(β)-3.6(α, β)-difuranose (2), die zu 5 dimerisiert werden kann. In 5 liegt ein symmetrisches heptacyclisches Ringsystem mit zentralem Piperazinring vor.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1621-1630 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Monosaccharides Containing Nitrogen in the Ring, XXVII. Pyrolytic Rearrangement of 4-Amino-4-deoxy-L-xylose to 4-Amino-4-deoxy-L-lyxosePyrolysis of the periodate degradation product 2 results in the rearrangement of the L-xylo-to the L-lyxo-configuration and the formation of 4-amino-4-N, 5-O-carbonyl-2,3-O-isopropy-liden-4-deoxy-α-L-lyxofuranose (5). Free 4-amino-4-deoxy-L-lyxose is formed from 5 via the bisulfite adduct 13, which exists as an equilibrium mixture of the pyrrolidine-forms 14 ⇋ 15 ⇋ 18 The bis-pyrrolidine-form 18 predominates under anhydrous conditions. The dimeric structure of 18 is established by mass spectra of the pentaacetate 16 and the TMS-ether 17.
    Notes: Durch Pyrolyse des Perjodat-Spaltproduktes 2 erfolgt Umlagerung der L-xylo-in die L-lyxo-Konfiguration, und es wird 4-Amino-4-N.5-O-carbonyl-2.3-O-isopropyliden-4-desoxy-α-L-lyxofuranose (5) erhalten. Aus 5 ist über das Schwefligsäure-Addukt 13 freie 4-Amino-4-desoxy-L-lyxose darstellbar, die im Gleichgewicht der Pyrrolidin-Formen 14 ⇋ 15 ⇋ 18 vorliegt. Die Bis-Pyrrolidin-Form 18 überwiegt stark in der wasserfreien Substanz. Die dimere Struktur von 18 ergibt sich aus den Massenspektren des Pentaacetats 16 und des TMS-Äthers 17.
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    Berichte der deutschen chemischen Gesellschaft 103 (1970) 
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    Keywords: Chemistry ; Inorganic Chemistry
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    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1664-1673 
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    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with N-Halogenphosphoranyliden-thiophosphoryldihalogenide AmidesThe reaction of S=PX2N=PF3 (X=F, Cl) with Si—N-compounds afforded the new compounds 1-11. It was proved that substitutions occurred only at the -N=PF3 group and that isomeric compounds were not formed. The reaction of S=PCl2N=PF3 and S=PFClN=PF3 with excess PF3Cl2 resulted in the formation of S=PCl2N=PFCl2 (12). The compounds 1, 2 are cleaved with water-free HBr at the P—N-bond to form the compounds 13, 14. The reaction of SPF2N=PF3 with amines yielded various products. The compounds 1-12 are much more stable towards hydrolysis than the starting compounds. 1H-, 19F-n.m.r., i.r., and mass spectra are reported and partially discussed.
    Notes: Durch Umsetzung von S=PX2N=PF3 (X=F, Cl) mit Si-N-Verbindungen erhielten wir die neuen Verbindungen 1-11. Wir konnten wahrscheinlich machen, daß die Substitutionen an der - N = PF3-Gruppe erfolgen und daß die isomeren Verbindungen dabei nicht ent-stehen. Die Reaktion von S=PCl2N=PF3 oder S=PFClN = PF3 mit überschüssigem PF3Cl2 führt zu S=PCl2N=PFCl2 (12). Die Verbindungen 1, 2 lassen sich mit wasserfreiem HBr an der P —N-Bindung spalten, wobei die Verbindungen 13, 14 entstehen. Die Umsetzung von S=PF2N=PF3 mit Aminen ergibt verschiedene Produkte. Die Verbindungen 1-12 sind gegen Hydrolyse stabiler als die Ausgangsverbindungen. 1H-, 19F-NMR-, IR- und Massenspektren werden mitgeteilt und teilweise diskutiert.
    Additional Material: 1 Ill.
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  • 92
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1792-1796 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Glycosides of Amino Sugars, II. Synthesis of 2-amino-2-deoxy-α-D-glucopyranosidesThe synthesis of glycosides and disaccharides of 2-amino-2-deoxy-D-glucose has been explored using trifluoroacetyl as the N-blocking group. Because of its high tendency for neighboring group participation only β-D-glycosides were formed. The corresponding α-disaccharide could be obtained as the main product when employing 2.4-dinitrophenyl as the N-protecting group.
    Notes: Die N-Trifluoracetyl-Schutzgruppe wurde zur Synthese von Glykosiden und Disacchariden der 2-Amino-2-desoxy-D-glucose benutzt. Sie zeigte eine hohe Tendenz zur Nachbargruppen-beteiligung unter Bildung von -β-D-Glykosiden. Das entsprechende α-Disaccharid wurde als Hauptprodukt bei Verwendung der N-2.4-Dinitrophenyl-Schutzgruppe erhalten.
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  • 93
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Isolation, Structure, and Synthesis of 5,6,7,4′-Tetrahydroxy-3′-methoxyflavone (Batatifoline), a new Flavone from Mikania batatifolia D.C.The flavone batatifoline has been isolated from Mikania batatifolia D. C. (Compositae). Its structure has been confirmed as 5,6,7,4′-tetrahydroxy-3′-methoxyflavone (1) by synthesis of the isomers 1 and 5,6,3′,4′-tetrahydroxy-7-methoxyflavone (5, Pedalitine).
    Notes: Aus Mikania batatifolia D. C. (Compositae) wurde das Flavon Batatifolin isoliert und ihm durch Synthese der Isomeren 5.6.7.4′-Tetrahydroxy-3′-methoxy-flavon (1) und 5.6.3′.4′-Tetra-hydroxy-7-methoxy-flavon (5, Pedalitin) die Struktur 1 zugeordnet.
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  • 94
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1886-1893 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polyacetylenic Compounds, 175. Synthesis and Biogenesis of Anthemis-thioethersThe configurations of four isomeric naturally occuring thioethers are established by synthesis and a detailed analysis of the n. m. r. spectra. By feeding of 3H-labelled 1-4 the biogenesis of a phenylthioether is further confirmed.
    Notes: Die Konfigurationen von vier natürlich vorkommenden Thioäthern werden durch Synthese und eine eingehende Analyse der NMR-Spektren sichergestellt. Durch Verfütterung von 3H-markierten 1-4 wird die Biogenese eines Phenylderivates weiter gesichert.
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  • 95
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 2024-2033 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Racemization in Peptide SynthesesVarious gaschromatographic racemization tests indicate, that 3-hydroxy-4-oxo-3,4-dihydro-1,2,3-benzotriazine as additive to DCCD decreases racemization in the DCCD-method to a minimum, compared with a series of N-hydroxy-compounds. It is also possible to prepare the intermediate activated esters without racemization. Addition of weak tertiary bases has a favourable effect on the yield and racemization in the preparation of N-acylpeptide-N-hydroxysuccinimide esters by the DCCD-method.
    Notes: Durch Anwendung mehrerer gaschromatographischer Racemisierungstests wurde gefunden, daß bei der DCCD-Methode1) aus einer Reihe von N-Hydroxyverbindungen als Zusatz zum DCCD das 3-Hydroxy-4-oxo-3.4-dihydro-1.2.3-benzotriazin die Racemisierung am wirkungsvollsten senkt. Auch eine racemisierungsfreie Voraktivierung ist mit dieser Verbindung möglich. Bei der Herstellung von N-Acyl-peptid-[N-hydroxy-succinimidestern] nach der DCCD-Methode wirkt sich ein Zusatz schwacher tert. Basen günstig auf Ausbeute und Racemisierung aus.
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  • 96
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 2077-2083 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ions, II. Wittig Olefination with Phosphonium FluoridesPhosphonium fluorides are available by ion exchange and can be used for the Wittig reaction without an auxiliary base.
    Notes: Phosphoniumfluoride sind durch Ionenaustausch zugänglich und gehen ohne Hilfsbase die Wittig-Reaktion ein.
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  • 97
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organic Phosphorus Compounds, 65. The Selective Elimination of Allyl Groups from Allylphosphonium, -arsonium and -sulfonium Salts and from Allyl sulfones by CyanolysisKCN cleaves allylphosphonium, -arsonium, and -sulfonium salts to give methacrylonitrile and tertiary phosphines, tertiary arsines or thioethers, respectively. Phosphonium and arsonium salts with four different ligands can be built up by alternate cyanolysis and quaternization. Allylammonium salts do not undergo the reaction, nor do allylphosphine oxides and dialkyl allylphosphonates. On the other hand, ally sulfones react with KCN to afford good yields of methacrylonitrile and sulfinic acids.
    Notes: KCN spaltet Allylphosphonium-, -arsonium- und -sulfoniumsalze in Methacrylnitril und tertiäre Phosphine, tertiäre Arsine und Thioäther auf. Durch alternierende Cyanolyse und Quartärisierung können Phosphonium- und Arsoniumsalze mit vier verschiedenen Liganden aufgebaut werden. Allylammoniumsalze, Allylphosphinoxide und -phosphonsäureester können nicht gespalten werden. Dagegen liefern Allylsulfone mit KCN in guten Ausbeuten Methacrylnitril und Sulfinsäuren.
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  • 98
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    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 2768-2774 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Stereochemistry and Solvolysis of some 3,4-Disubstituted ChromansReduction of 3-bromachromanone-(4) and of 3-bromo-2,6- dimethylchromanone-(4) yields the cis-3-bromo-4- hydroxychromans 1 and 2 which we converted to the trans-3,4-dihalogenochromans 8-11. Hydrolysis of 8-11 produces the trans-3-bromo-4-hydroxychromans 3 and 4; Solvolysis with alkohols yields the trans -3-bromo-4-alkoxychromans 5-7; by reaction with phenol we got the 3-bromo-4-arylchroman 12.
    Notes: Reduktion von 3-Brom-chromanon-(4) und 3-Brom-2.6 - dimethyl-chromanon-(4) liefert die 3c-Brom-4r -hydroxy-chromane 1 und 2, welche in die 3t.4r-Dihalogen-chromane 8-11 umgewandelt wurden. Die Hydrolyse von 8-11 ergibt die 3t-Brom- 4r-hydroxy-chromane 3 und 4; die Solvolyse mit Alkoholen führt zu den 3t- Brom-4r-alkoxy-chromanen 5-7; bei der Umsetzung mit Phenol haben wir dagegen das 3-Brom-4-aryl-chroman 12 erhalten.
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  • 99
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 2784-2793 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hindered Rotation about the Arsenic and Antimony Nitrogen BondProton n. m. r. of aminoarsines and aminostibines of the type [(CH3)3C]2El-N[M(CH3)3]2 (El = As, Sb; M = Si, Ge) has been measured as a function of temperature. At 35° 4a, 4d, and 6c possess gauche-configuration with hindered rotation about the El—N bond. The corresponding ΔG≠ -values are 〉 23.2 kcal/Mol for 4a, 22.8 kcal/Mol for 4d and 19.6 kcal/ Mol for 6c. Comparison of 4a, 4d, and 6c with 6a, 6b, 7, and 8 supports the hypothesis that steric interactions and not (p→d)π-bonds between the El-N bond cause this hindered rotation. The proton n. m. r. spectra of 4b, 4c, 4e, and 5 give evidence that in the case of 4b, 4c, and 4e rotamers with different population are formed at 35°, whereas in the case of 5 only one rotamer is formed at 35°.
    Notes: Temperaturabhängige 1 H-NMR-Untersuchungen an Aminoarsinen und Aminostibinen des Typs [(CH3)3C]2El-N[M(CH3)3]2(El = As, Sb; M = Si, Ge) zeigen, daß 4a, 4d und 6c bei 35° in der gauche-Form mit rotationsgehinderter El-N-Bindung vorliegen. Die entsprechenden ΔG≠-Werte betragen für 4a 〉 23.2 kcal/Mol, für 4d 22.8 kcal/Mol und für 6c 19.6 kcal/Mol. Die Hypothese, daß diese Rotationsbehinderung auf sterische und nicht auf (p→d)π-Wechselwirkung zurückzuführen ist, wird durch die Vergleichssubstanzen 6a, 6b, 7 und 8 erhärtet. Für 4b, 4c, 4e und 5 geben die 1H-NMR-Spektren einen Hinweis darauf, daß 4b, 4c und 4e bei 35° Rotamere unterschiedlicher Population, 5 ausschließlich ein Rotameres bildet.
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  • 100
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 2836-2844 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Substituted Rheniumcarbonyl Chlorides with Ligands Containing OxygenPolymeric [Re(CO)3Cl]x is extremely reactive even toward very weak ligands containing oxygen. Thus monomeric and dimeric compounds have been obtained with aliphatic alcohols. The resulting complexes contain sp3-hybridized oxygen-metal bonds. Compounds of the same type are also form ed with ethers such as diisopropylether and dioxane. With monodentate ketones predominantly complexes of the dimeric type [Re(CO)3LKetCl]2 have been obtained. Only with acetone has a monomeric compound Re(CO)3L2Cl been isolated. 1,2- and 1,3- diketones generally act as bidentate ligands yielding stable 5- or 6-membered ring complexes, which, however, are not innercomplexes, as they contain only Re-O-π-bonds. -The Structure of the compounds has been elucidated by i. r. and mass spectra as well as by molecular weight measurements.
    Notes: Polymeres [Re(CO)3Cl]x ist selbst gegenüber sehr schwachen sauerstoffhaltigen Liganden äußerst reaktiv. So wurden mit aliphatischen Alkoholen ein- und zweikernige Verbindungen, z. B. Re(CO)3L′AlCl (L′Al = HOC2H4OH) bzw. [Re(CO)3LAlCl]2 (LAl = i-C3H7OH, i-C4H9OH), erhalten. Die Bindung erfolgt über sp3-hybridisierten Sauerstoff an das Metall. Komplexe des gleichen Typs entstehen auch mit äthern, wie Diisopropyläther und Dioxan. Mit monofunktionellen Ketonen wurden vorwiegend Komplexe vom zweikernigen Typ [Re(CO)3LKetCl]2 mit „ylid“-artiger Bindung der Liganden an das Metallatom gebildet. Lediglich mit Aceton wurde eine einkernige Verbindung Re(CO)3L2Cl isoliert. 1.2- und 1.3- Diketone fungieren im allgemeinen als zweizählige Liganden unter Ausbildung stabiler Fünf-bzw. Sechsring-Chelatkomplexe, die jedoch nicht Innerkomplexe sind, d. h. nur Re-O-π-Bindungen enthalten. -Die Struktur der Verbindungen wurde durch IR-Spektren, Massenspektren und Molgewichtsbestimmungen sichergestellt.
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