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  • 1
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    Perspectives on European Earthquake Engineering and Seismology : Volume 1 (2014)
    Cham : Springer
    Details
    Keywords: Engineering ; Natural disasters ; Geotechnical engineering ; Civil engineering ; Engineering ; Civil Engineering ; Natural Hazards ; Geotechnical Engineering & Applied Earth Sciences
    Description / Table of Contents: Preface --- 1. The Full-Scale Laboratory: The Practice of Post-Earthquake Reconnaissance Missions and Their Contribution to Earthquake Engineering --- 2. Rapid Earthquake Loss Assessment after Damaging Earthquakes --- 3. Existing Buildings: The New Italian Provisions for Probabilistic Seismic Assessment --- 4. Seismic Response of Precast Industrial Buildings --- 5. The Role of Site Effects at The Boundary Between Seismology and Engineering: Lessons from Recent Earthquakes --- 6. Seismic Analysis and Design of Bridges with an Emphasis to Eurocode Standards --- 7. From Performance- and Displacement-Based Assessment of Existing Buildings per EN1998-3 to Design of New Concrete Structures in Fib MC2010 --- 8. Testing Historic Masonry Structural Elements and/or Building Models --- 9. Earthquake Risk Reduction: From Scenario Simulators Including Systemic Interdependency to Impact Indicators --- 10. Physics-Based Earthquake Ground Shaking Scenarios in Large Urban Areas --- 11. A Seismic Performance Classification Framework to Provide Increased Seismic Resilience --- 12. Towards Displacement-Based Seismic Design of Modern Unreinforced Masonry Structures --- 13. Pushover Analysis for Plan Irregular Building Structures --- 14. Recent Development and Application of Seismic Isolation and Energy Dissipation and Conditions for Their Correct Use --- 15. Conservation Principles and Performance-Based Strengthening of Heritage Buildings in Post-Event Reconstruction --- 16. Earthquake Risk Assessment: Present Shortcomings and Future Directions --- 17. The Role of Pile Diameter on Earthquake-Induced Bending --- 18. Predictive Models for Earthquake Response of Clay and Quick Clay Slopes.- 19. Recent Advances in Seismic Soil Liquefaction Engineering --- 20. Seismic Hazard and Seismic Design and Safety Aspects of Large Dam Projects
    Pages: Online-Ressource (VIII, 650 pages) , 373 illustrations, 263 illustrations in color
    ISBN: 9783319071183
    URL: https://link.springer.com/openurl?genre=book&isbn=978-3-319-07118-3
    Language: English
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    E-BOOK
  • 2
    Unknown
    Perspectives on European Earthquake Engineering and Seismology : Volume 1 (2014)
    Cham : Springer
    Details
    Keywords: Engineering ; Natural disasters ; Geotechnical engineering ; Civil engineering ; Engineering ; Civil Engineering ; Natural Hazards ; Geotechnical Engineering & Applied Earth Sciences
    Description / Table of Contents: Preface --- 1. The Full-Scale Laboratory: The Practice of Post-Earthquake Reconnaissance Missions and Their Contribution to Earthquake Engineering --- 2. Rapid Earthquake Loss Assessment after Damaging Earthquakes --- 3. Existing Buildings: The New Italian Provisions for Probabilistic Seismic Assessment --- 4. Seismic Response of Precast Industrial Buildings --- 5. The Role of Site Effects at The Boundary Between Seismology and Engineering: Lessons from Recent Earthquakes --- 6. Seismic Analysis and Design of Bridges with an Emphasis to Eurocode Standards --- 7. From Performance- and Displacement-Based Assessment of Existing Buildings per EN1998-3 to Design of New Concrete Structures in Fib MC2010 --- 8. Testing Historic Masonry Structural Elements and/or Building Models --- 9. Earthquake Risk Reduction: From Scenario Simulators Including Systemic Interdependency to Impact Indicators --- 10. Physics-Based Earthquake Ground Shaking Scenarios in Large Urban Areas --- 11. A Seismic Performance Classification Framework to Provide Increased Seismic Resilience --- 12. Towards Displacement-Based Seismic Design of Modern Unreinforced Masonry Structures --- 13. Pushover Analysis for Plan Irregular Building Structures --- 14. Recent Development and Application of Seismic Isolation and Energy Dissipation and Conditions for Their Correct Use --- 15. Conservation Principles and Performance-Based Strengthening of Heritage Buildings in Post-Event Reconstruction --- 16. Earthquake Risk Assessment: Present Shortcomings and Future Directions --- 17. The Role of Pile Diameter on Earthquake-Induced Bending --- 18. Predictive Models for Earthquake Response of Clay and Quick Clay Slopes.- 19. Recent Advances in Seismic Soil Liquefaction Engineering --- 20. Seismic Hazard and Seismic Design and Safety Aspects of Large Dam Projects
    Pages: Online-Ressource (VIII, 650 pages) , 373 illustrations, 263 illustrations in color
    ISBN: 9783319071183
    URL: https://link.springer.com/openurl?genre=book&isbn=978-3-319-07118-3
    Language: English
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    E-BOOK
  • 3
    Electronic Resource
    Electronic Resource
    Circling behavior induced by phencyclidine in mice and its inhibition by naloxone (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 73-74 
    Details
    ISSN: 1420-9071
    Keywords: Mice ; circling behavior ; phencyclidine ; naloxone ; hyperactivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Phencyclidine (PCP), when given to mice, induces general hyperactivity and rapid circling, similar to that caused by morphine. These effects are partially antagonized by naloxone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02005882
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  • 4
    Electronic Resource
    Electronic Resource
    Antagonistic effect of progesterone towards estradiol dipropionate-induced changes in glycogen content in uterus and vagina of P-mice (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 1455-1456 
    Details
    ISSN: 1420-9071
    Keywords: Mice ; uterus ; vagina ; sex steroids ; glycogen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Estradiol dipropionate induces an increase (3-fold) in the uterine glycogen content and a decrease (4-fold) in the vaginal glycogen content of Parkes (P) mice. Progesterone antagonizes this estradiol dipropionate-induced response in both the uterine and vaginal tissue. The degree of this antagonism is more pronounced in the uterus than in the vagina.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01950032
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  • 5
    Electronic Resource
    Electronic Resource
    Incorporation of32P into renal phospholipids of mice during postnatal growth (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 1184-1186 
    Details
    ISSN: 1420-9071
    Keywords: Mice ; phospholipids ; kidney growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary During the first 40 days of life the rate of incorporation of32P into total phospholipids and into phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, sphingomyelin, diphosphatidylglycerol, phosphatidic acid and phosphatidylinositol of mouse kidney was by some 25–35% higher than in older animals. Results suggest a different involvement of cellular membranes during of normal and compensatory renal growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01951720
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  • 6
    Electronic Resource
    Electronic Resource
    L3T4(CD4)-, Lyt-2(CD8)- and Mac-1(CD11b)-phenotypic leukocytes in murine cryptococcal meningoencephalitis (1995)
    Springer
    Mycopathologia 131 (1995), S. 159-166 
    Details
    ISSN: 1573-0832
    Keywords: Cryptococcus ; Immunity ; Immunohistology ; Meningoencephalitis ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract An immunohistological study of L3T4(CD4)+ and LYT-2(CD8)+ lymphocytes, Mac-1(CD11b)+ monocytes and granulocytes in experimental murine cryptococcal meningoencephalitis was conducted. To assess the concomitant inflammatory reaction in an extracerebral site, livers were examined in parallel. Mice were infected i.v. withCryptococcus neoformans, group A/D, and organs were examined immunohistologically for CD4-, CD8- and monocyteand granulocyte-specific CD11b-phenotypic leukocytes over a period of 60 days. Intracerebrally, agglomerations of cryptococci formed pseudocysts that were surrounded by CD4+ and CD8+ lymphocytes at the end of the second week post-infection, followed by the invasion of monocytes and granulocytes into the lesions. After the fourth week post-infection, most of the invaded lesions were transformed into glious scars. Meningitis was usually marked and showed a homogenous distribution of CD4-, CD8- and CD11b-phenotypic cells, with a predominance of monocytes and CD4+ lymphocytes. Inflammatory infiltrates in the liver were found already 4 days post-infection. CD4+ lymphocytes and monocytes were distributed homogenously in the infiltrates, with a lower number of CD8+ lymphocytes being located rather in the periphery of the infiltrates. Comparing leukocyte kinetics in brain and liver, an important observation was the delayed immigration of immune cells at the intracerebral cryptococcal lesions as compared with the liver, and the different migration patterns of T-lymphocyte subgroups and macrophages. These results suggest that there are differential leukocyte migration patterns in the liver and brain following disseminated cryptococcosis. The immunological aspects of the observed leukocyte kinetics are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01102895
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  • 7
    Electronic Resource
    Electronic Resource
    Evaluating birth frequencies and embryonic lethality in transgenesis following pronuclear injection of HIV DNA (1995)
    Springer
    Journal of biomedical science 2 (1995), S. 146-153 
    Details
    ISSN: 1423-0127
    Keywords: Transgene ; Mice ; Embryogenesis ; HIV ; Toxicity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The likelihood that expression of a foreign gene in a mammalian cell is deleterious to viability is confronted whenever novel transgenic animals are made. A pathological response to transgene expression is even desired in transgenic mouse models of human disease. The derivation of HIV-transgenic mice in our laboratory using multiple recombinant forms of an HIV provirus has resulted in mixed success best explained by the variable toxicity of the different transgenes. Employing a standardized approach to pronuclear injections, experimental variation amongst recombinant HIV transgenes was documented in terms of the percentage of pregnancies following embryo transfer into pseudopregnant mice and the percentage of transplanted embryos leading to term births in these pregnant females (giving rise to an index of birth success, SI). Results compiled over 5 years suggested that the SI reflected transgene toxicity, in this case of HIV gene products early in embryogenesis. These observations have guided the design of productive transgenes for mouse models of HIV-related diseases and may be generally applicable in transgenesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02253065
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  • 8
    Electronic Resource
    Electronic Resource
    Neutralizing antibody provided protection against enterovirus type 71 lethal challenge in neonatal mice (2000)
    Springer
    Journal of biomedical science 7 (2000), S. 523-528 
    Details
    ISSN: 1423-0127
    Keywords: Enterovirus type 71 ; Experimental infection ; Mice ; Neutralizing antibody ; Vaccine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Experimental infection with enterovirus type 71 (EV71) induced death in neonatal mice in an age- and dose-dependent manner. The mortality rate was 100% following intraperitoneal inoculation 1-day-old ICR mice and this gradually decreased as the age at the time of inoculation increased (60% in 3-day-old mice and no deaths occurred in mice older than 6 days of age). A lethal dose greater than 108 PFU was necessary. Lethargy, failure to gain weight, rear limb tremors and paralysis were observed in the infected mice before death. EV71 was isolated from various tissues of the dead mice. Using a reverse transcription polymerase chain reaction technique with a specific primer pair, a 332-bp product was detected in the tissues that produced a culture positive for EV71. Protection against EV71 challenge in neonatal mice was demonstrated following passive transfer of serum from actively immunized adult mice 1 day after inoculation with the virus. Pups from hyperimmune dams were resistant to EV71 challenge. Additionally, maternal immunization with a formalin-inactivated whole-virus vaccine prolonged the survival of pups after EV71 lethal challenge.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02253368
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  • 9
    Electronic Resource
    Electronic Resource
    Transgenic markers for mammalian chimeras (1988)
    Springer
    Development genes and evolution 197 (1988), S. 63-65 
    Details
    ISSN: 1432-041X
    Keywords: Chimeras ; In situ hybridization ; Mice ; Transgenic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary We describe the construction of aggregation chimeras between normal and transgenic embryos containing multiple copies of mouse β-globin genes. The transgenic component of the chimeras is then detected in tissue sections by a DNA-DNA in situ hybridization technique, using a biotinylated DNA β-globin probe and an avidin-linked alkaline phosphatase detection system. The general advantages of transgenic markers for chimeras are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00375928
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  • 10
    Electronic Resource
    Electronic Resource
    Effect of aminoglutethimide on murine fetal hepatic erythroid colony formation (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 498-500 
    Details
    ISSN: 1420-9071
    Keywords: Mice ; pregnant ; aminoglutethimide phosphate ; mice ; liver ; fetal ; erythroid colony-forming cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pretreatment of pregnant mice with aminoglutethimide phosphate, an inhibitor of glucocorticoid synthesis, increases the content of fetal liver erythroid colony-forming cells (CFU-E), as assessed by the formation of erythroid colonies in vitro by fetal liver cells in plasma clots containing exogenous erythropoietin. In addition, the inability of aminoglutethimide to influence erythroid colony formation in vitro suggests that endogenous glucocorticoids exert a suppressive effect on the number of functional CFU-E in the fetal liver.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01966168
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  • 11
    Electronic Resource
    Electronic Resource
    Sperm enzyme activity analysis in individual sperm for detection of heritable mutations in mammals (1988)
    Springer
    Cellular and molecular life sciences 44 (1988), S. 253-254 
    Details
    ISSN: 1420-9071
    Keywords: Mice ; heritable mutations ; sperm enzyme activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Male mice were injected i.p. with 2.5 mg/kg mitomycin C, 100 mg/kg ethyl nitrosourea or saline and mated with untreated virgin females five weeks later. Sperm from 64 of the F1 male progeny were analyzed histochemically for acrosin, succinic dehydrogenase and alpha-glycerophosphate dehydrogenase activity. The frequency of F1 males with sub-normal sperm enzyme activity was significantly higher among progeny from treated males than in controls. These results show that analysis of sperm enzyme activity in F1 males is a practical method for detection of transmitted mutations induced in a treated parent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01941727
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  • 12
    Electronic Resource
    Electronic Resource
    Heterosis among lines of mice selected for body weight (1985)
    Springer
    Theoretical and applied genetics 71 (1985), S. 52-56 
    Details
    ISSN: 1432-2242
    Keywords: Heterosis ; Reproduction ; Mice ; Body weight
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To examine the effect of selection for body weight on levels of heterosis for reproductive traits, crosses were made between three groups of six lines of mice, one group unselected (controls) and the other two selected for high (large lines) and low (small lines) 6-week body weight, respectively. The coefficient of inbreeding of each line was about 0.60. In a comparison of purebred and crossbred progeny, both out of purebred mothers, there was on average 4% heterosis for number born, 3% for percentage weaned and 8% for numbers weaned. In a comparison of purebred and crossbred mothers, each mated to males of an unrelated strain and dissected on the 17th day of gestation, crossbreds had on average 1.6 more live embryos, which was 22% of the purebred mean. This comprised an increase of 0.6 corpora lutea, of 0.4 in survival to implantation and of 0.6 in subsequent survival to 17 days. The heterosis was similar whether the mothers had parents of the same or different size.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00278253
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  • 13
    Electronic Resource
    Electronic Resource
    Growth and body composition changes in mice selected for high post-weaning weight gain on two levels of feeding (1987)
    Springer
    Theoretical and applied genetics 73 (1987), S. 926-931 
    Details
    ISSN: 1432-2242
    Keywords: Selection ; Feeding levels ; Growth ; Body composition ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Two lines of mice were selected for high post-weaning weight gain (3 to 6 weeks) adjusted for 3 week weight. One line (F) was grown on freely available food and the other (S) on a feeding scale set at the same level for all mice. Food intake of the S line averaged 80% of the F line. The realised heritabilities after 6 generations of selection were 0.38±0.06 and 0.33±0.07 for the F and S lines, respectively. In generation 7, mice from the F and S lines and from an unselected control line (C) were compared on both free and set levels of feeding from 3 weeks to 9 weeks of age. Measurements taken were growth rate, appetite, food conversion efficiency (weight gain/food intake) and body composition (fat, protein, ash, water). The F and S lines grew more rapidly and efficiently than the C line on both levels of feeding, each line performing best on the level of feeding on which it was selected. The average genetic correlation between growth rates of the same line on the two feeding levels was 0.54±0.10. The F line grew 19% faster and was 9% more efficient than the S line on free feeding but the S line grew 15% faster and was 15% more efficient than the F line on set feeding. Relative to the C line, food intake per day on free feeding was 4% higher in the F line and 6% lower in the S line. There was no difference between the lines in food intake/g body weight. The rate of deposition of all body components increased in both selection lines. In the F, S and C lines respectively, efficiencies of gains in body components (102x gain/food) were 1.79, 1.31 and 1.06 for fat, 1.53, 1.63 and 1.22 for protein and 5.88, 6.45 and 4.98 for protein + water. Apparently energy lost as heat was reduced in both the F and S lines. The partitioning of energy retained was altered in favour of more fat in the F line and more protein in the S line.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00289400
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  • 14
    Electronic Resource
    Electronic Resource
    Correlated responses in development and distribution of fat depots in mice selected for body composition traits (1989)
    Springer
    Theoretical and applied genetics 78 (1989), S. 217-223 
    Details
    ISSN: 1432-2242
    Keywords: Correlated responses ; Fat depots ; Lean tissue ; Body composition ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Development of adipose tissue in five depots was investigated in mice selected for high or low 12-week epididymal fat pad weight as a percentage of body weight (HF and LF lines), or high or low 12-week hind carcass weight as a percentage of body weight (HL and LL lines). An unselected control line (RC) was maintained. Hind carcass (HC) and fat pads from subcutaneous hindlimb, subcutaneous forelimb, gonads, kidneys and mesentery were dissected and weighed at 4, 6, 9, 12 or 15 weeks of age. Generally, body weight (BW), daily gain (DG), feed intake (FI), feed efficiency (FE) and feed intake/metabolic body weight (FC) were higher (P≤0.05) in HF than in LF, and in LL than in HL. HF had more fat (as a percentage of BW) than LF in all depots (P≲-0.01), and asymmetry (P≤0.01) was detected for gonadal fat. LL consistently had a higher (P≤0.01) fat percentage than HL, and asymmetry (P≤0.01) was observed for perirenal fat. At age of selection, ranking of fat depot weights as a percentage of total fat depot weight was not changed by selection; however, gonadal fat accounted for more of the total fat in HF and LL compared with RC, while the opposite was found in LF and HL. HC percentage was higher (P≤0.01) in HL than LL, and higher (P≤0.01) in LF than HF. Growth rate of each fat depot relative to BW was not affected by selection. These results demonstrated that selection for proportion of fat in one depot or for HC percentage changed fat percentage in other depots. However, the rate of fat deposition in each depot relative to body weight gain was not altered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00288802
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  • 15
    Electronic Resource
    Electronic Resource
    Long-term restricted index selection in mice designed to change fat content without changing body size (1995)
    Springer
    Theoretical and applied genetics 91 (1995), S. 340-345 
    Details
    ISSN: 1432-2242
    Keywords: Selection index ; Restricted index ; Fat ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The objective of this study was to determine if low secondary selection differentials, caused by selecting within full-sib families, may have accounted for the failure of an intended restricted selection index to reduce epididymal fat pad weight (EF) without changing body weight (BW) in mice. Replicate lines that had been selected within full-sib families for high (HE) or low (LE) EF, while holding BW constant, were crossed. After two generations of random mating, two replicates were sampled and selection initiated for the same restricted index criteria except that mass selection was used to increase the selection differentials. In both phases of selection the HE restricted index selection, designed to increase EF without altering BW, was in agreement with expectation. In contrast, the LE index, designed to decrease EF without changing BW, did not agree with theory since BW increased while EF decreased only slightly. Therefore, reduced selection differentials could not explain the deviation from theory. A possible explanation may reside in the restricted selection index being more sensitive to changes in genetic parameters due to shifts in gene frequency as a consequence of the selection applied. However, linkage disequilibrium and genetic drift can not be ruled out as contributing factors to the asymmetry of response.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00220897
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  • 16
    Electronic Resource
    Electronic Resource
    Comparison of lifetime performance in mice under crisscross, repeat hybrid male cross and random mating systems (1985)
    Springer
    Theoretical and applied genetics 69 (1985), S. 447-455 
    Details
    ISSN: 1432-2242
    Keywords: Crossbreeding ; Lifetime performance ; Mating system ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Mating systems that capitalize on heterosis in dairy cattle are the criss-cross (CC), the repeat hybrid male cross (RHMC) and random mating within a synthetic population (SYN). When performance is determined solely by direct additive genetic and dominance genetic effects, expected performance under CC (averaged over four generations after F1 generation), relative to that under RHMC (or SYN) is (59 G1+69 G2 +82 H)/64(G1+G2+H), where Gi is direct additive genetic effect of breed i and H is direct heterosis. Five CC, five RHMC and one SYN population of mice were prepared to test 533, 534 and 410 females, respectively for performance during lifetime (155 days after mating). Each female was pair-mated at day 42 with a male from the SYN population and the number of lactations during the lifetime (NL), total number (TN) and weight (TW in g) of young born alive during lifetime, total number (AN) and weight (AW in g) of young raised to weaning (18 days), and actual length of reproductive life (RL in days) were recorded. Observed performance averaged over four generations was, under CC, RHMC and SYN, 4.74, 4.62 and 4.56 for NL, 49.9, 48.2 and 48.8 for TN, 86.0, 83.6 and 85.1 g for TW, 47.5, 45.5 and 46.3 for AN, 512.1, 517.9 and 521.1 g for AW, and 120.0, 117.6 and 116.7 for RL, respectively. Heterosis due to the female (H) was 10, 30, 33, 34, 43 and 9% for NL, TN, TW, AN, AW and RL, respectively. Direct additive genetic values were estimated for each pair of lines involved with CC or RHMC. These values were used in the formula to calculate expected performance in each mating system. The ratio of CC to RHMC for the expected and observed performance was 1.01 and 1.01 for NL, 1.04 and 1.04 for TN, 1.04 and 1.03 for TW, 1.04 and 1.04 for AN, 1.05 and 0.99 for AW, and 1.01 and 1.02 for RL, respectively. The ratio of CC to SYN for the observed performance was 1.04 for NL, 1.02 for TN, 1.01 for TW, 1.03 for AN, 0.98 for AW, and 1.03 for RL. As expected, the observed mean performance under CC was slightly larger than that under RHMC or SYN.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00251082
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  • 17
    Electronic Resource
    Electronic Resource
    Selection for fertility in mice — the selection plateau and how to overcome it (1985)
    Springer
    Theoretical and applied genetics 70 (1985), S. 72-79 
    Details
    ISSN: 1432-2242
    Keywords: Mice ; Selection experiments ; Plateau ; Fertility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A long-term experiment for increasing the traits first day litter size (LS1) and litter weight (LW1) was conducted with two populations for 33 generations. The selection plateau was reached in population DU-C (selection and estrus synchronization (h2 = 0.02±0.01); in population DU-K (selection) the plateau (h2 = 0.05±0.2) was nearly reached. Selection progress per generation was in LS1 b = 0.11±0.02; b = 0.12±0.04 (1st to 18th generation DU-K, DU-C) and b = 0.10±0.03; b = 0.07±0.05 (19th to 33rd generation, DU-K, DU-C) in LW1 b = 0.16±0.04 g; 0.19±0.07 g (DU-K, DU-C) b = 0.20±0.09 g; 0.001±0.09 g (DU-K, DU-C). Reverse and relaxe selection as well as systematic inbreeding was applied for 10 generations. Reverse selection yielded h2 = 0.28±0.11 (R-DU-K) and h2 = 0.17±0.05 (R-DU-C) and showed that there was still additive genetic variance. Relaxe selection did not cause alterations in the selection parameters, whereas inbreeding lead to inbred depressions (b = LS1 = −0.42±0.15; −0.45±0.12; b = LW1 = −1.13±0.20; −0.82±0.18 I-DU-K, I-DU-C). The plateau was based upon the heterozygote advantage. Several methods for overcoming the plateau were applied. A new selective useful variance could be created by crossing the plateau populations (h2 = 0.14±0.04). A short-term progress in overcoming the plateau (1st to 3rd generation) could be obtained by litter size standardization (LS = 388). Tandem selection (selection for body weight — BW42) as well as crossing of inbred strains were not suitable for overcoming the selection plateau. Altering the environmental conditions as a possibility for overcoming the plateau has been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00264485
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  • 18
    Electronic Resource
    Electronic Resource
    Heterosis among lines of mice selected for body weight (1985)
    Springer
    Theoretical and applied genetics 71 (1985), S. 44-51 
    Details
    ISSN: 1432-2242
    Keywords: Heterosis ; Mice ; Selection ; Growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary To examine the effect of selection on levels of heterosis, crosses were made between three groups of six lines of mice, one group unselected (controls) and the other two selected for high (large lines) and low (small lines) 6-week body weight, respectively. The coefficient of inbreeding of each line was about 0.60. Each line was crossed reciprocally to one line from each of the parental groups, as well as producing purebred progeny. Heterosis for 3-week weight, 6-week weight and 3–6 week gain averaged 0.0%, 2.4% and 4.2%, respectively, and was higher for males than for females. Heterosis was more extensive in crosses involving large or control lines than in crosses with small lines. There was no detectable heterosis in several measures of developmental rate, such as age at vaginal opening. Food conversion efficiency and carcass composition were measured on a sample of the animals. Food consumption, gonadal fat pad weight, and hindquarters weight, each expressed as a proportion of body weight, exhibited −4.0%, 5.6%, and 2.3% heterosis, respectively.
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    URL: http://dx.doi.org/10.1007/BF00278252
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    Partitioning of genetic effects on lifetime performance of mice (1985)
    Springer
    Theoretical and applied genetics 71 (1985), S. 250-257 
    Details
    ISSN: 1432-2242
    Keywords: Mice ; Lifetime ; Performance ; Additive ; Maternal ; Heterosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A total of 2,457 lifetime performance records of 29 genetic groups of mice was analyzed using multiple regression of records on the proportion of gene contribution from 6 lines (designated as Lines MP, mQ, WP, wQ, CP and cQ). Genetic effects were partitioned into line additive, line maternal, direct heterosis, maternal heterosis and paternal heterosis effects. The line additive and line maternal effects were expressed as deviations from Line cQ. Seventeen of 25 line additive effects differed significantly (P〈0.05) from Line cQ whereas only 4 of 25 line maternal effects deviated significantly from Line cQ. Deviations in line additive effects from cQ were negative in all lines examined whereas deviations in line maternal effects from cQ were all positive, indicating a negative relationship between line additive and line maternal effects. Direct heterosis effects were all positive and significant (P 〈 0.01) except in the MPxWP cross which was produced by mating Lines MP and WP of the same base population (P). Maternal heterosis effects were significant in 10 of 20 cases whereas paternal heterosis effects were significant in 13 of 20 cases. Although direct heterosis is a major component of total heterosis effects (sum of direct, maternal and paternal heterosis), the results suggest that parental heterosis may need to be considered in producing multiple way crosses. The fitting of line additive, line maternal, direct heterosis, maternal heterosis and paternal heterosis effects in the multiple regression model effectively accounted for all genetic effects in lifetime performance.
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    URL: http://dx.doi.org/10.1007/BF00252063
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    Maturing patterns of organ weights in mice selected for rapid postweaning gain (1986)
    Springer
    Theoretical and applied genetics 73 (1986), S. 148-157 
    Details
    ISSN: 1432-2242
    Keywords: Mice ; Correlated responses ; Organ growth ; Degree of maturity ; Allometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Correlated responses to selection for increased 3–6 week postweaning gain in male mice were estimated for seven internal organs (testes, spleen, liver, kidneys, heart, small intestine (S intest) and stomach) weighed at specific degrees of maturity in body weight (37.5, 50.0, 62.5, 75.0, 87.5 and 100%). Correlated responses in organ weights were generally large, but the magnitude and direction of response depended upon whether 1) comparisons were made at the same age, degree of maturity or body weight and 2) absolute or proportional organ weights were used. The selected line (M16) weighed more and had larger organ weights than controls (ICR) when compared at either the same degree of maturity or the same age, indicating positive genetic correlations between body weight and the respective organ weights. Positive correlated responses were found in spleen weight/body weight at all degrees of maturity and in liver and S intest weights as a proportion of body weight at some degrees of maturity. Testes, kidneys, heart and stomach weights as a proportion of body weight had negative correlated responses, though this was consistent only for kidneys across all degrees of maturity. Correlated responses in organ weights adjusted for body weight by covariance analysis were positive for spleen, S intest and stomach and negative for testes and kidneys. Based on the constrained quadratic model, degree of maturity in organ weight relative to degree of maturity in body weight responded positively for testes, kidneys and S intest and negatively for spleen and liver. Selection for increased growth caused negative correlated responses in allometric growth of testes, kidneys, S intest and stomach.
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    URL: http://dx.doi.org/10.1007/BF00273732
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    Selection for weight gain in mice at two ages and under ad libitum and restricted feeding (1988)
    Springer
    Theoretical and applied genetics 75 (1988), S. 415-423 
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    ISSN: 1432-2242
    Keywords: Mice ; Selection ; Gain ; Feed restriction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Direct and correlated responses in weight gain and body weights were assessed for nine generations of within-family selection. Four selection criteria were used: gain between 28 and 38 or 48 and 58 days of age, and under two feeding regimes, i.e. ad libitum consumption or 80% of the control line. Direct responses to selection and realized heritabilities in the ad libitum lines were greater in the first period. Weight gain under ad libitum feeding at later ages appeared to have a lower genetic variability. In the restricted lines the responses and realized heritabilities were higher in the second period. Selection under restricted feeding in both periods led to animals that had lower weight gains than the control line when compared under ad libitum feeding.
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    URL: http://dx.doi.org/10.1007/BF00276744
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    Selection for weight gain in mice at two ages and under ad libitum and restricted feeding (1988)
    Springer
    Theoretical and applied genetics 75 (1988), S. 424-431 
    Details
    ISSN: 1432-2242
    Keywords: Mice ; Selection ; Body composition ; Gain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Correlated responses in feed efficiency, feed consumption and body composition were investigated after nine generations of selection for weight gain in two age intervals, 28 to 38 or 48 to 58 days old, and under ad libitum feed consumption or intake restricted to 80% of the control lines. Correlated responses in feed efficiency and feed consumption in the ad libitum lines were positive in the early period and negative in the late period. Restricted lines had a positive response in feed efficiency and a negative response in consumption in both periods of selection. Changes in body composition in the early period were the same in all selected lines: a lower crude protein percentage at the start of the period and a lower ash percentage at the end of the period. Body composition at the start of the late period was not altered by selection, while at the end of the period ad libitum lines had higher dry matter percentages and restricted lines had lower fat and higher ash percentages. Body composition at 100 days old was not affected by selection except for dry matter percent, which was lower in the restricted lines.
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    URL: http://dx.doi.org/10.1007/BF00276745
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    Phenotypic and genetic variability of estimated growth curve parameters in mice (1988)
    Springer
    Theoretical and applied genetics 76 (1988), S. 148-156 
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    ISSN: 1432-2242
    Keywords: Growth curve ; Genetic parameters ; Heritability ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Data from 1,919 outbred ICR mice were used to examine the potential usefulness of growth curve parameters as selection criteria for altering the relationship between body weight and age. A logistic growth function was used to model growth through 12 weeks of age. Estimates of asymptotic weight (A), maximum growth rate (r) and age at point of inflection (t*) were obtained by nonlinear least-squares. A log transformation was also used to stabilize residual variance. Phenotypic and genetic parameters were estimated for the estimated growth curve parameters and for body weights at 2, 3, 4.5, 6, 8 and 12 weeks of age. Heritabilities of estimated growth curve parameters (obtained with and without a log transformation, respectively) were: A (0.28±0.07, 0.28±0.07), r (0.35±0.07, 0.53±0.09) and t* (0.41±0.08, 0.44±0.08). Estimated genetic correlations suggest that t* may be useful in selecting for rapid early growth without increasing mature weight.
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    URL: http://dx.doi.org/10.1007/BF00288846
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    Divergent selection for in vitro developmental capacity of preimplantation mouse embryos (1988)
    Springer
    Theoretical and applied genetics 76 (1988), S. 467-472 
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    ISSN: 1432-2242
    Keywords: Selection ; Embryo development ; Embryo culture ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Replicated divergent selection was conducted for two generations in ICR mice for in vitro developmental capacity (IVDC; percentage of fertilized one-cell zygotes developing to blastocysts in vitro per female donor). Realized heritabilities based on high and low selection were 0.03±0.08 and −0.11±0.09 in replicate 1, and 0.10±0.11 and 0.08±0.10 in replicate 2. No differences were detected between selection lines (P〉0.2) or replicates (P〉0.1). Estimate of heritability in the base population based on 332 daughter-dam pairs was 0.14±0.18. These results indicate that additive genetic variance contributes little to the phenotypic variance in this trait. Considerable phenotypic variation in IVDC was observed (mean=49.3; SD=31.0), with a range of IVDC from 0%–100%. Utilization of donor female as a blocking factor is suggested for designs of experiments with preimplantation embryos to increase precision and power of statistical analyses.
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    URL: http://dx.doi.org/10.1007/BF00265352
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    Selection for components related to body composition in mice: direct responses (1987)
    Springer
    Theoretical and applied genetics 74 (1987), S. 793-801 
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    ISSN: 1432-2242
    Keywords: Mice ; Fat ; Lean tissue ; Selection ; Heritability ; Genetic correlation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Replicated within full-sib family single-trait selection was conducted for 10 generations in mice for (1) high or low 12-week epididymal fat pad percentage (100 x epididymal fat pad weight/body weight) or (2) high or low 12-week hind carcass percentage (100 x hind carcass weight/body weight). Pooled realized heritabilities based on high, low and divergent selection were 0.66±0.09, 0.65±0.13 and 0.66±0.05 for epididymal fat pad percentage and 0.48±0.08, 0.33±0.08 and 0.40±0.04 for hind carcass percentage. The pooled realized genetic correlation (rG R) between epididymal fat pad percentage and hind carcass percentage based on divergence was −0.67±0.04. Other estimates of (rG R) were: epididymal fat pad percentage with body weight (0.57±0.05); epididymal fat pad percentage with epididymal fat pad weight (1.17±0.05); hind carcass percentage with body weight (−0.61±0.09); hind carcass percentage with hind carcass weight (−0.05±0.11). Indirect measures of fat and lean tissue percentages were highly heritable, and (rG R) between them would be desirable from the standpoint of analogous types of traits in livestock. In the same context, undesirable (rG R)'s were found between epididymal fat pad percentage and body weight and between hind carcass percentage and body weight.
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    URL: http://dx.doi.org/10.1007/BF00247559
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    Selection for fertility in mice using different methods of litter size manipulation (1987)
    Springer
    Theoretical and applied genetics 75 (1987), S. 147-150 
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    ISSN: 1432-2242
    Keywords: Mice ; Selection experiments ; Maternal effects litter size manipulation ; Fertility
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A short-term selection experiment for increasing the first-day litter size (LS1) and 28-day litter weight (LW28) was conducted with three populations of mice over 8 generations. Different methods of litter size manipulation were used for the populations — in S the litter size was standardized to 8 (4 ♂ ♂, 4 ♀♀) on the first day, in LA it was adjusted to the average size of all litters born on the same day and NL had the natural litter size. To eliminate temporary environmental effects, a control population was kept in each case. The selection results per generation were, for LS 1 b=0.30 (S, NL) and 0.20 (LA), and for LW28 b=5.62 g (S), 5.26 g (NL), and 4.32 g (LA). The heritability obtained was between 0.18 and 0.13 for LS 1 and from 0.42 to 0.12 for LW28. The populations differed in the correlated responses for body weight parameters (litter weight gain). The implantation rate increased in populations S and NL (b=0.19, 0.37), but not in population LA. Postnatal mortality went down (b=-0.07) and the dam's milk production rose (b=1.11 g) only in population LA. The estimated partial regression coefficient linking body weight at mating (BWM) for the dam and the daughter's litter size showed an effect on the litter size.
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    URL: http://dx.doi.org/10.1007/BF00249156
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    Selection for components related to body composition in mice: correlated responses (1987)
    Springer
    Theoretical and applied genetics 75 (1987), S. 177-188 
    Details
    ISSN: 1432-2242
    Keywords: Correlated responses ; Mice ; Body composition ; Growth ; Fat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Correlated responses were estimated in each of two replicate lines of mice selected within full-sib families for high (HF) or low (LF) 12-week epididymal fat pad weight as a percentage of body weight (epididymal fat pad percentage), or high (HL) or low (LL) 12-week hind carcass weight as a percentage of body weight (hind carcass percentage). Two replicate control lines (RC) were maintained. Correlated traits were measured in each of the 10 generations of selection. Realized (rG R) and offspring-sire genetic correlations generally were in agreement. In HF and LF, 3–6 week postweaning gain (rG R = 0.36±0.04) and feed intake (rG R = 0.50±0.13) had positive correlated responses, but feed efficiency and feed intake/metabolic body size did not change. Positive correlated responses were found for subcutaneous fat pad percentage, body weight-adjusted subcutaneous fat pad weight and fat percentage in the hind carcass (rG R's were 1.04±0.13, 0.93±0.13 and 0.90±0.08). In the hind carcass, fat-free dry (protein + ash) percentage showed a small negative correlated response, and fat-free dry weight did not change. In HL and LL, the correlated responses for the above traits were generally opposite to those observed in HF and LF. Litter size, percentage of infertile matings, and preweaning mortality showed no consistent correlated responses in any of the lines, but an index of fitness combining the three traits showed a decrease in all four selection treatments.
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    URL: http://dx.doi.org/10.1007/BF00249161
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    Morphologic analysis of long-term bone marrow cultures that support B-lymphopoiesis or myelopoiesis (1985)
    Springer
    Cell & tissue research 239 (1985), S. 375-382 
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    ISSN: 1432-0878
    Keywords: B-lymphocytes ; Long-term bone marrow cultures ; Stromal cells ; Hemopoietic microenvironment ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A comparative morphological analysis of the Whitlock-Witte long-term B-cell culture and the predominantly myeloid Dexter long-term bone marrow culture demonstrates that similarities and differences exist between the two systems. Cells from the long-term B-cell cultures have a characteristic lymphoid morphology, whereas those from the Dexter cultures are predominantly granulocytes and macrophages along with a few undifferentiated blast cells. A multilayered stromal cell layer is a common feature of both systems. Scanning electron micrographs show the cells in this layer to be large, irregularly shaped and flattened. The data further indicate that there are unique features in the relationship between developing B cells and stromal cells in the long-term B-cell cultures. Large, mononuclear cells are present that have numerous membrane infoldings within which numerous lymphoid cells lie. The relationship of these cells to macrophages and epithelial/reticular cells is discussed.
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    URL: http://dx.doi.org/10.1007/BF00218018
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    Morphological changes in the submandibular glands and in the X zone of the adrenal gland following ovariectomy in mice (1986)
    Springer
    Cell & tissue research 246 (1986), S. 549-556 
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    ISSN: 1432-0878
    Keywords: Submandibular gland ; Adrenal X zone ; Ovariectomy ; Morphometrical analysis ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphological changes in submandibular glands of female mice following ovariectomy were studied morphometrically by light microscopy and ultrastructurally by electron microscopy. The X zone of the adrenal gland was examined in order to assess possible changes that might be expected to occur after ovariectomy. In submandibular glands, 1 to 4 weeks after ovariectomy, no changes were observed in percentages of the acinar, intercalated duct, and granular convoluted tubular areas occupying photomicrographs. However, an increase in the granular content of both intercalated duct and granular convoluted tubular cells was recognized. By contrast, the glandular picture 4 months after ovariectomy changed remarkably, resembling that of the male mouse both morphometrically and in terms of fine structure. In the adrenal cortex of control female mice, the X zone became thinner with aging. As compared with this, the X zone of ovariectomized mice at any time after the operation was thicker than that of controls. These observations suggest that the absence of ovarian hormones in the ovariectomized mouse may lead to prolonged functioning of X zone cells, which in turn may cause masculinization of the submandibular gland.
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    URL: http://dx.doi.org/10.1007/BF00215195
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    Histological changes in spleen and lymph nodes of mice administered cyclophosphamide and levan (1986)
    Springer
    Cell & tissue research 245 (1986), S. 183-188 
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    ISSN: 1432-0878
    Keywords: Spleen ; Lymph nodes ; Mice ; Cyclophosphamide ; Levan ; Light microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Morphological changes in spleen and lymph nodes of C57B1 mice induced by the cytotoxic agent cyclophosphamide and the polysaccharide levan, separately and in combination were studied. In the spleen, an early decrease (phase 1) and a late increase (phase 2) in weight were found to result from all drug administrations. The hypocellularity of phase 1 was due to a depletion in the white pulp affecting mainly the B-region. Splenic weight decrease was parallel to B-cell depletion and most marked in animals exposed to cyclophosphamide with levan. The splenomegaly observed during phase 2 with all treatments was due to extramedullary hematopoiesis in the red pulp. In the lymph nodes, administration of cyclophosphamide and levan produced opposite effects on the B-cell region: cyclophosphamide eliminated the germinal centers for 8 days, but levan seemed to enhance B-cell activity. In animals given both cyclophosphamide and levan, inhibition of B-cell activity began earlier than with cyclophosphamide alone. Levan does not antagonize the suppressive effect of cyclophosphamide on the B-cell component at the early phase when the drugs are given together.
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    Retarded myogenic cell replication in regenerating skeletal muscles of old mice: an autoradiographic study in young and old BALBc and SJL/J mice (1995)
    Springer
    Cell & tissue research 280 (1995), S. 277-282 
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    ISSN: 1432-0878
    Keywords: Key words: Skeletal muscle ; Regeneration ; Ageing ; Strain-specific muscle precursor replication ; Autoradiography ; Mice ; BALBc (SJL/J)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract. The patterns of skeletal muscle precursor cell replication after crush injury were compared by the use of autoradiographic techniques, in young (4-week-old) and old (39-week-old) BALBc and SJL/J mice. Similar comparisons were made between cut and crush lesions in old BALBc muscle. Muscle precursor cell replication commenced at 18–24 h after injury in both young and old muscles from both strains of mice. In young BALBc muscle the peak of myogenic activity at 60 h was 36 h earlier than in old mice. SJL/J muscle responded more rapidly than did BALBc: in young SJL/J the peak myogenic activity was at 46 h (14 h earlier than in young BALBc muscle), and in old SJL/J muscle the peak activity at 72 h was 24 h earlier than in old BALBc muscle. In all mice (both young and old) myogenic cell replication was substantially reduced by 120 h after injury. A comparison of the timing of muscle precursor cell replication in cut and crush lesions in old BALBc mice revealed a more rapid response in the cut lesion; this difference between the lesions is comparable with data from identical lesions in 6–8-week-old BALBc mice (McGeachie and Grounds 1987). However, the peak of myogenic replication in the older mice in the present study was some 26–36 h later than in the younger 6–8-week-old mice. These experiments show that, whilst muscle precursor cell replication commences at approximately the same time (about 24 h) after injury in young and old mice, the peak level of activity is delayed by some 24–36 h in old mice. In addition, the SJL/J mouse strain responds more rapidly and prolifically to muscle injury than does the BALBc strain.
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    Sertoli cells in the testis and epithelium of the ductuli efferentes are targets for 3H 1,25 (OH)2 vitamin D3 (1987)
    Springer
    Cell & tissue research 247 (1987), S. 453-455 
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    ISSN: 1432-0878
    Keywords: 1,25(OH)2 vitamin D3 ; Testis ; Ductuli efferentes ; Sertoli cells ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Evidence from results of autoradiographic studies in mice indicates that nuclei of Sertoli cells and of epithelial cells in the ductuli efferentes contain receptors for 1,25(OH)2 vitamin D3.
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    URL: http://dx.doi.org/10.1007/BF00218327
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    Myosin content and vasoconstrictive ability of the proximal and distal (renin-positive) segments of the preglomerular arteriole (1987)
    Springer
    Cell & tissue research 248 (1987), S. 579-588 
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    ISSN: 1432-0878
    Keywords: Afferent glomerular arteriole ; Renin ; Myosin ; Juxtaglomerular cells ; Tubulo-glomerular feedback ; Rats ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The PAP-technique and antibodies to myosin were used to demonstrate the prerequisites for vasoconstriction in the juxtaglomerular part of the preglomerular arteriole as compared with its proximal segment in rats and mice. In contrast with the myosin-positive/renin-negative proximal part of the afferent arteriole no myosin-like activity could be demonstrated in its distal, renin-positive part. In accordance, no thick myofilaments were found in fully differentiated juxtaglomerular epithelioid cells replete with mature secretory granules. Stimulation of the renin-angiotensin system was followed by an increase of the reninpositive/myosin-negative portions of the preglomerular arteriole. Marked interspecies and internephron variations in the length of this vessel segment under control and stimulated conditions were observed. The juxtaglomerular part of the preglomerular arteriole close to the macula densa seems therefore to have only limited capabilities for vasoconstriction. This finding may be of importance regarding the tubulo-glomerular feedback, a mechanism allegedly triggered by the so-called ‘macula densa-signal’. It is suggested that this non-contractile segment of the afferent arteriole may represent the renal vascular receptor responsible for the increase of renin secretion during pressure reduction. Unlike the afferent arterioles, most of the efferent arterioles showed the highest level of their weak but distinct myosin-like immunoreactivity in the juxtaglomerular region, indicating some efferent juxtaglomerular vasoconstrictive ability.
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    Disorganization of stroma alters epithelial differentiation of the glandular stomach in adult mice (1986)
    Springer
    Cell & tissue research 243 (1986), S. 65-68 
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    ISSN: 1432-0878
    Keywords: Epithelial differentiation ; Stomach ; Duodenum ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The response of adult epithelium in contact with heterologous mesenchymes/stromas was studied in three digestive organs (forestomach, glandular stomach, and duodenum). After various tissues were implanted beneath the epithelial layer of adult mice, the epithelial differentiation was examined after sacrifice of animals at intervals up to 24 weeks. In the forestomach and duodenum, the epithelial differentiation was not affected at all by the tissue implantation. In the glandular stomach, in contrast, epithelial cells exhibited altered differentiation in which chief and parietal cells disappeared and were replaced by columnar epithelial cells with PAS-positive granules. These epithelial cells often formed immature villi. Such differentiation-altered columnar epithelium (DACE) was induced by implanting any type of tissue and even by sham operation, indicating that it was induced by disorganization of the tissue-implanted stroma. The size of DACE was significantly influenced by the stage of implanted tissue; 14.5-day fetal mesenchyme induced the largest DACE, and was followed by 16.5-day fetal mesenchyme, adult stroma, and sham operation. These results suggest the importance of stromal organization in maintaining epithelial differentiation in the glandular stomach.
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    Co-housing in a stable hierarchical group is not aversive for dominant and subordinate individuals (2000)
    Springer
    Neuroscience and behavioral physiology 30 (2000), S. 195-200 
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    ISSN: 1573-899X
    Keywords: Mice ; dominance ; subordinacy ; stress ; aggression ; locomotor activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The behavior of individaals and their responses to external stimuli are controlled by the microsocial environment, which for most mammals is associated with dominant-subordinate relationships. Physiological and behavioral differences between dominant and subordinate individuals may be ‘primary’ (genetically determined) or ‘secondary’ (due to position in the group's hierarchical structure). A series of experiments was conducted to investigate the physiological (pain response threshold), immunological (thymus, spleen weights, primary immune response), and behavioral (motor activity, behavior in a shuttle box test) characteristics of dominant and subordinate individuals in groups of three laboratory mice formed on the basis of linear hierarchy. Assessment of the effects of group conditions was made using a conditioned reflex location preference test. The results showed: 1) there are no statistically significant differences in physiological and behavioral (except for motor activity) parameters between dominant and subordinate mice; 2) co-housing of dominant and subordinate individuals in groups with stable hierarchical relationships was not aversive for them.
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    Issues in the genetics of social behavior: Revisited (1996)
    Springer
    Behavior genetics 26 (1996), S. 463-470 
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    ISSN: 1573-3297
    Keywords: Mice ; agonistic behavior ; aggression ; homogeneous set ; standard tester ; social behavior
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Though social behavior has not been overlooked by behavior geneticists, the number of studies is small when compared to those on individual traits. One reason for the neglect may be the difficulty of making connections between genes and social behaviors, which by definition involve the interaction of two or more organisms. Fuller and Hahn (1976) addressed this issue and described three means of establishing social groups that would facilitate genetic analysis. We survey the literature on agonistic behavior in mice from 1976 through 1994 and describe interesting uses of those three methods. One of those methods (the standard tester design) often employs a “noninteractive” social partner. We present data showing that the standard tester design may be more valuable when using an evocative and interactive standard tester.
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    Effect of laser therapy on wound contraction and cellularity in mice (1986)
    Springer
    Lasers in medical science 1 (1986), S. 125-130 
    Details
    ISSN: 1435-604X
    Keywords: Wound contraction ; Fibroblasts ; Infrared laser ; Helium-neon laser ; Mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Physics , Technology
    Notes: Abstract The effect was investigated of combined pulsed infrared and continuous wave heliumneon mid-laser therapy on wound contraction and wound bed cellularity, and the effects were compared of variation in the infrared pulsing frequency. The laser used was the Space Mix-5 Mid-Laser and the wounds studied were full-thickness excised skin lesions made in the flank skin of CD1 adult female mice, which were maintained under general anaesthesia during both excision and irradiation. Treatment at 700 Hz increased wound contraction in comparison with treatment at 1200 Hz, when all other controllable parameters were kept constant. By 11 days after injury the cellularity of the wound bed was greater in the wounds treated with 700 Hz than in those treated with 1200 Hz, with the greatest difference being found in the number of fibroblasts, the cells primarily responsible for wound contraction.
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    Einfluß der Substituenten auf Aktivierungsenthalpie-,-entropie und -volumen beim Zerfall organischer Perester (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 240-245 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Influence of Substituents on the Enthalpy, Entropy and Volume of Activation in the Decomposition of Organic PerestersThe influence of the ester group on the decomposition of organic peroxides was studied on peresters of the pivalic and neodecanoic acid with tert-butyl, tert-amyl, 1-methyl-1-propylpentyl and 1,1,4-trimethylpentyl groups at temperatures of 393 to 473 K and pressures up to 3000 bar using a flow method. As expected the half-live times decrease with increasing temperature and increase with rising pressure. With increasing bulkiness of the substituents the rates of decomposition as well as the enthalpies of activation increase. This surprising fact can be explained by the simultaneous increase of the entropies and the volumes of activation.
    Notes: Der Einfluß der Estergruppe auf den Zerfall organischer Peroxide wurde an Perestern der Pivalin- und der Neodecansäure mit tert-Butyl-, tert-Amyl-, 1-Methyl-propylpentyl- sowie 1,1,4-Trimethylpentylresten bei Temperaturen von 393 bis 473 K und Drücken bis 3000 bar in einer Strömungsapparatur untersucht. Die Zerfallshalbwertszeiten nehmen erwartungsgemäß mit steigender Temperatur stark ab und mit steigendem Druck zu. Mit zunehmender Größe der Substituenten steigen sowohl die Zerfallsgeschwindigkeiten als auch die Aktivierungsenthalpien. Dieser überraschende Effekt kann durch die Vergrößerung der Aktivierungsentropie und des Aktivierungsvolumens erklärt werden.
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    Zur Lewis-Acidität von Nickel(0), III. Alkalimetall-hydridotrialkylaluminat-Komplexe von Ni(CDT) (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 313-322 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Lewis Acidity of Nickel(0), III. Alkali Metal Hydridotrialkylaluminate Complexes of Ni(CDT)Ni(CDT) reacts with hydridotrialkylaluminates of the alkali metals in ether/THF or ether/amine mixtures at temperatures below -50°C to form the temperature-sensitive compounds [MA(n-Donor)n]+[R3Al—H—Ni(CDT)]- (1-7) (MA = Li, Na; R = Me, Et, iBu). An Al—H—Ni three-centre bond is present in these complexes. On the basis of NMR data, the strength of the hydridoaluminate-nickel bond and the charge on nickel, caused by the hydridoaluminate residue, are compared with the corresponding characteristics of other ligand-Ni(CDT) complexes in which donor-acceptor σ-bonds are present.
    Notes: Ni(CDT)Abkürzungen: CDT = trans, trans, trans-1,5,9-Cyclododecatrien, COD = 1,5-Cyclooctadien, MA+ (solvatisiertes) Alkalimetall-Ion, PMDTA = N,N,N′,N″N″-Pentamethyldiethylentriamin, TMEDA = N,N,N′,N′-Tetramethylethylendiamin. reagiert mit Alkalimetall-hydridotrialkylaluminaten in Ether/THF-oder Ether/Amin-Mischungen als Lösungsmittel unterhalb von -50°C zu den thermisch labilen Verbindungen [MA(n-Donor)n]+[R3Al—H—Ni(CDT)]- (1-7) (MA = Li, Na; R = Me, Et, iBu). In diesen Komplexen liegt eine Al—H—Ni-Mehrzentrenbindung vor. Anhand NMR-spektroskopischer Daten lassen sich die Stärke der Hydridoaluminat-Nickel-Bindung und die Beladung des Nickels durch den Hydridoaluminat-Rest mit den Bindungsverhältnissen in anderen Ligand-Ni(CDT)-Komplexen mit Donor-Akzeptor-σ-Bindungen vergleichen.
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    Zur Lewis-Acidität von Nickel(0), I. Methyllithium-Komplexe von Nickel(0) (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 275-297 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Lewis Acidity of Nickel(0), I. Methyllithium Complexes of Nickel(0)The synthesis and properties of the methyllithium complexes of nickel(0) of the type (n-Donor)m-(LiCH3)Ni0(π-Ligand)n (1a-c, 16a-c, 20a-c) [n-Donor = chelating amine or THF; π-Ligand = CDT, ethene, or CO] are described. The structure of (PMDTA)(LiCH3)Ni(C2H4)2 (1b) has been determined by X-ray crystallography.  -  In these ate complexes, a carbanionic methyl group is σ-bonded to a nickel atom, the acceptor strength of which depend on the π-ligands. The chemical and spectroscopic properties indicate that the Ni—CH3 bond in the carbonyl complex is largely covalent whereas in the CDT and ethene compounds it is more polar. The CDT complex is thermolabile in solution. The findings are in agreement with the following series of increasing acceptor strength: Ni(CDT) 〈 Ni(C2H4)2 〈 Ni(CO)3.
    Notes: Es wird über die Synthese und Eigenschaften der Methyllithium-Komplexe von Nickel(0) (n-Donor)m(LiCH3)Ni0(π-Ligand)n Wir bezeichnen mitπ-Liganden solche Liganden, die als π-Akzeptoren mit einem Übergangsmetallatom dπ—pπ—oder dπ—dπ-Rückbindungen auszubilden vermögen (Alkene, CO, auch Phosphane);n-Donoren solche Liganden, die als „harte Basen“ (Ether, Amine) über ihre freien Elektronenpaare vornehmlich Hauptgruppenmetall-Ionen, d.h. „harte Säuren“ komplexieren;σ-Donoren solche Liganden, die  -  ohne über Akzeptororbitale zu verfügen  -  entweder polare Bindungen enthalten und Mehrzentrenbindungen eingehen können (Metallalkyle und -hydride) oder ein freies Elektronenpaar bereitstellen (Carbanionen, Phosphorane, Hydrid-Ion), wobei σ-Bindungen zu einem niederwertigen Übergangsmetallatom ausgebildet werden. (1a-c, 16a-c, 20a-c) mit Chelataminen oder THF als n-Donoren und CDTAbkürzungen: CDT = trans,trans,trans-l,5,9-Cyclooctadien; COT = Cyclooctatetraen; PMDTA = Pentamethyldiethylentriamin; TMEDA = Tetramethylethylendiamin; MA+A = Alkalimetall- bzw. quartäres Ammonium-Kation., Ethen oder CO als π-Liganden berichtet. Die Struktur von (PMDTA)(LiCH3)Ni(C2H4)2 (1b) wurde röntgenographisch bestimmt.  -  In diesen at-Komplexen ist eine carbanionische Methylgruppe über eine σ-Bindung an ein Nickelatom gebunden, dessen Akzeptorstärke von den π-Liganden abhängt. Chemische und spektroskopische Eigenschaften der Komplexe lassen für CDT oder Ethen als π-Liganden auf vergleichsweise polare, für den CDT-Komplex in Lösung dazu thermolabile Ni—CH3-Bindungen schließen, während für den Carbonyl-Komplex aufgrund von 13C-NMR-Daten eine überwiegend kovalente Ni—CH3-Bindung anzunehmen ist. Die Befunde stehen mit folgender Reihe zunehmender Akzeptorstärke im Einklang: Ni(CDT) 〈 Ni(C2H4)2 〈 Ni(CO)3.
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    Über das korrespondierende Verhalten von heteroatom-stabilisierten Carbokationen und dem Cycloheptatrien-Norcaradien-Gleichgewicht (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 620-633 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Correspondence of Heteroatom-stabilized Carbocations and the Cycloheptatriene-Norcaradiene EquilibriumThe effects of alkoxyiminium substituents on the cycloheptatriene-norcaradiene equilibria 1 ⇄ 2 have been investigated. Due to the energetics two classes of compounds were found (ΔH° 〈 0, and ΔH° 〉 0). The transfer of the substituent effect from carbocation to carbocyclus is inhibited by a p-phenylene group. From 1H and 13C NMR spectra at variable temperatures thermodynamic parameters are deduced and correlated with σR-constants obtained from 19F NMR spectroscopy. By extrapolation, the enthalpy difference for the unsubstituted cycloheptatriene and norcaradiene is calculated as 9.3 kcal/mol.
    Notes: Der Einfluß von Alkoxyiminium-Substituenten an C-7 auf die Lage des Cycloheptatrien-Norcaradien-Gleichgewichts 1 ⇄ 2 wird untersucht. Auf Grund der Energetik gibt es Verbindungen, bei denen Temperaturabsenkung eine Verschiebung des Gleichgewichts zum Norcaradien (ΔH° 〈 0) ergibt, bei anderen Beispielen ist ΔH° 〈 0. Eine p-Phenylenbrücke zwischen Kation und Carbocyclus blockiert den Substituenteneffekt. Aus den 1H- und 13C-NMR-Spektren bei verschiedenen Temperaturen wurden thermodynamische Daten ermittelt und mit den durch 19F-NMR bestimmten σR-Konstanten korreliert. Durch Extrapolation konnte die Enthalpiedifferenz des unsubstituierten Cycloheptatriens und Norcaradiens zu 9.3 kcal/mol abgeschätzt werden.
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    Hydrated oxocarbons, IV. Silylation of 1,1-dihydroxy compounds (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 661-669 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hydratisierte Oxokohlenwasserstoffe, IV. Silylierung von 1,1-Dihydroxy-VerbindungenDie Anwendung von verschiedenen Silylierungsreagenzien auf mono- und polyvicinale 1,1-Di-hydroxy-Verbindungen wurde untersucht. Mit einigen dieser Reagenzien konnten aus Ninhydrin (2) und Rhodizonsäure (17) die entsprechenden geminalen Bis(trimethylsilyloxy)-Derivate 1 und 20 gewonnen werden. Während 1 leicht zu Hexamethyldisiloxan und Indantrion (4) fragmentiert, ist 20 thermisch relativ stabil, es gibt pyrolytisch bei 500°C nur Spuren des Tetraketons 21 ab. Andere Silylierungsreagenzien bewirken unerwartete C-Alkylierung oder C-Amidierung am Dihydroxykohlenstoff. Silylierungen von Perhydroxycyclobutan und -cyclohexan führen zu Ringaufspaltungs- bzw. Verengungsprodukten.
    Notes: The action of various silylating agents on mono- and polyvicinal 1,1-dihydroxy compounds has been investigated. Some of these reagents converted ninhydrin (2) and rhodizonic acid (17) into the corresponding geminal bis(trimethylsilyloxy) derivatives 1 and 20, respectively. Compound 1 readily fragments to form hexamethyldisiloxane and indantrione (4). The rhodizonic acid derivative 20 is, however, rather stable and even on pyrolysis at 500°C gives only traces of the tetraketone 21. With other silylating agents unexpected C-alkylation or C-amidation at the dihydroxy carbon is observed. Silylation of perhydroxycyclobutane and -cyclohexane leads to ring opened and contracted products.
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    Cycloadditionen des Triphenylallenyl-Kations mit Cyclopentadien  -  Studium des Reaktionsmechanismus unter stabilen Ionen-Bedingungen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 694-703 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadditions of the Triphenylallenyl Cation with Cyclopentadiene  -  Investigation of the Reaction Mechanism under Stable Ion ConditionsThe triphenylallenyl cation (5) reacts with cyclopentadiene in a concerted [4 + 2] and a stepwise [2 + 2] cycloaddition. The reaction mechanisms are elucidated by NMR spectroscopic observation of the intermediate carbenium ions.
    Notes: Das Triphenylallenyl-Kation (5) geht mit Cyclopentadien eine konzertierte [4 + 2]- sowie eine stufenweise [2 + 2]-Cycloaddition ein. Die Reaktionsmechanismen werden durch NMR-spektro-skopische Beobachtung der intermediären Carbenium-Ionen aufgeklärt.
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    URL: http://dx.doi.org/10.1002/cber.19851180229
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    Synthese und Struktur Platin-haltiger Tripeldecker- und Tetradecker-Komplexe (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 729-740 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structure of Platinum-Containing Triple-Decker and Tetra-Decker ComplexesStacking of the acceptor sandwich bis(η5-2,3-dihydro-1H-1,3-diborolyl)platinum 1 (≙ (C2B2C)2Pt) with (C5H5)M fragments leads to the unsymmetrical triple-decker complexes (η5-C5H5)M-μ-(η5-C2B2C)Pt(η5-C2B2C) 2 (M = Co) and 3 (M = Ni) as well as to the symmetrical tetra-decker complexes [(η5-C5H5)M-μ-(η5-C2B2C)]2Pt 4 (M = Fe) and 5 (M = Ni). In these reactions 1 and (C5H5)Fe(C8H12) yield the tetra-decker 4, whereas with (C5H5)Co(C2H4)2 only the triple-decker 2 is formed. With [(C5H5)Ni(CO)]2 both the triple-decker 3 and the tetra-decker 5 are obtained. NMR studies on the diamagnetic complexes 2 (30 valence electrons), 4 (42 VE), and 5 (46 VE) indicate high-symmetrical conformations, or free rotation of the ligands. 2 and 3 crystallize isotypic; the X-ray structure analyses exhibit the triple-decker arrangement with antiperiplanar conformation of the heterocycles. 3 in comparison with 2 is elongated along the molecular axis. The tetra-deckers 4 and 5 also crystallize isotypic; for the first time a synclinale conformation of the bridging ligands is found.
    Notes: Aufstockung des Akzeptor-Sandwichs Bis(η5-2,3-dihydro-1H-1,3-diborolyl)platin 1 (≙ (C2B2C)2Pt) mit (C5H5)M-Fragmenten führt zu den unsymmetrischen Tripeldecker-Komplexen (η5-C5H5)M-μ(η5-C2B2C)Pt(η5-C2B2C) 2 (M = Co) und 3 (M = Ni) sowie zu den symmetrischen Tetradecker-Komplexen [(η5-C5H5)M-μ-(η5-C2B2C)]2Pt 4 (M = Fe) und 5 (M = Ni). Dabei ergibt die Reaktion von 1 mit (C5H5Fe(C8H12) den Tetradecker 4, während mit (C5H5)Co(C2H4)2 nur der Tripeldecker 2 entsteht. Mit [(C5H5)Ni(CO)]2 werden der Tripeldecker 3 und der Tetradecker 5 gebildet. NMR-Untersuchungen an den diamagnetischen Komplexen 2 (30 Valenzelektronen), 4 (42 VE) und 5 (46 VE) sprechen für hochsymmetrische Konformationen oder freie Rotation der Liganden. 2 und 3 kristallisieren isotyp; die Röntgenstrukturanalysen zeigen die Tripeldeckeranordnung mit antiperiplanarer Konformation der Heterocyclen. 3 ist im Vergleich zu 2 entlang der Molekülachse aufgeweitet. Die Tetradecker 4 und 5 kristallisieren ebenfalls isotyp, es wird erstmals eine synclinale Konformation der Brückenliganden gefunden.
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    Ein neuer Zugang zu Alkylthio(trifluoracetyl)furanen durch thermische [3 + 2]-Cycloadditionen neuer mesoionischer 1,3-Oxathiol-4-one an Alkine (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 785-795 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Entry to Alkylthio(trifluoroacetyl)furans by Way of Thermal [3 + 2]Cycloaddition Reactions of New Mesoionic 1,3-Oxathiol-4-ones to AlkynesAs cyclic carbonyl ylides, the novel 2-alkylthio-5-trifluoroacetyl-1,3-oxathiolylium-4-olates of type 1a-d combine with dimethyl acetylenedicarboxylate across the 2,5-position with formation of non-isolable primary adducts, which release COS to give the furandicarboxylic diesters 3a-d. Methyl propiolate reacts with 1a-c to produce mixtures of the regioisomeric furancarboxylic esters 4a-c and 5a-c, whose main components 4a-c are isolable. On the other hand, the reactions of phenylacetylene, 1-diethylaminopropyne, or (Z)-1-methoxy-1-buten-3-yne with 1a proceed with regiospecific formation of the furan derivatives 6, 7, or 8, respectively. The observed regioselectivities are qualitatively discussed on the basis of MO-perturbation theory.
    Notes: Als cyclische Carbonyl-ylide nehmen die neuen 2-Alkylthio-5-trifluoracetyl-1,3-oxathiolylium-4-olate vom Typ 1a-d in 2,5-Stellung Acetylendicarbonsäure-dimethylester unter Bildung nicht-isolierbarer Primäraddukte auf, die unter COS-Abspaltung Furandicarbonester 3a-d liefern. Mit Propiolsäure-methylester reagiert 1a-c zu Gemischen aus den regioisomeren Furancarbonestern 4a-c und 5a-c, deren Hauptkomponenten 4a-c isolierbar sind. Dagegen vereinigen sich Phenylacetylen, 1-Diethylaminopropin bzw. (Z)-1-Methoxy-1-buten-3-in mit 1a regiospezifisch zu den Furan-Derivaten 6, 7 bzw. 8. Die beobachteten Regioselektivitäten werden qualitativ auf der Basis der MO-Störungstheorie diskutiert.
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    Notizen. Thermolysis and photolysis of hexachloro-tris-σ-homotropone and related compounds (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 840-844 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermolyse und Photolyse von Hexachlor-tris-σ-homotropon und verwandten VerbindungenTroponethylenacetal (2) reagiert mit überschüssigem CCl2 zu den Mono-, Bis- und Tris-Addukten 3, 4a, b und 5. Thermolyse von 5 führt nicht zum Hexachlor-tris-σ-homobenzol (1), ebensowenig wie die Photolyse des Ketons 6a, bei der unter Öffnung einer Cyclopropan-Brückenbindung das sterisch mehr gehinderte Isomere 6b erhalten wird. Die Photolyse von 8 verläuft ebenfalls nicht unter Decarbonylierung (→ 7) sondern unter Cyclopropanring-Öffnung zu 9 bzw. 10, wobei hier die von der Carbonylgruppe am weitesten entfernten Bindungen geöffnet werden.
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    Schwefelextrusion aus 5(2H)-Isothiazolonen und 5(2H)-Isothiazolthionen zu intermediären Imidoylketenen und -thioketenen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 851-862 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sulfur Extrusion from 5(2H)-Isothiazolones and 5(2H)-Isothiazolethiones to give Intermediate Imidoyl Ketenes and Imidoyl ThioketenesFrom 5(2H-isothiazolethiones (2) and propylene oxide a series of new 5(2H-isothiazolones (7) was prepared. With tributylphosphane (or cyanide ions) 2 and 7 eliminated one sulfur atom. The resulting assumed imidoyl ketenes (8) and imidoyl thioketenes (3) could not be detected spectro-scopically. But by isolation of dimeric imidoyl thioketenes (1,3-dithietanes, 1) and trapping with alcohols, amines, or benzylideneisopropylamine to give derivatives of acrylic acid (4-6) or dihydropyrimidones (9) it is shown that 3 and 8 are probably intermediates.
    Notes: Aus 5(2H)-Isothiazolthionen (2) wurde mittels Propylenoxid eine Reihe neuer 5(2H)-Isothiazolone (7) hergestellt. Beide Substanzklassen reagieren mit Tributylphosphan (oder Cyanid-Ionen) unter Abspaltung eines Schwefelatoms zu vermuteten, spektroskopisch aber nicht nachgewiesenen Imidoyl-thioketenen (3) bzw. Imidoylketenen (8). Ihr intermediäres Auftreten wurde durch die Isolierung von dimeren Imidoyl-thioketenen (1,3-Dithietanen, 1) und durch Abfangreaktionen mit Alkoholen, Aminen oder Benzylidenisopropylamin zu den Derivaten der Acrylsäure 4-6 bzw. den Dihydropyrimidonen 9 wahrscheinlich gemacht.
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    Heterocyclische β-Enaminoester, 36. Das Cycloadditions-Ringerweiterungsprinzip beim 4,5-Dihydropyrrol: 6,7-Dihydro-1H-azepine, Pyrimido[4,5-b]azepine und 1,2,4-Triazolo[5′,1′: 2,3]pyrimido[4,5-b]azepin (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 863-872 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Heterocyclic β-Enamino Esters, 36. The Cycloaddition-Ring Enlargement Principle on 4,5-Dihydropyrroles: 6,7-Dihydro-1H-azepines, Pyrimido[4,5-b]azepines, and 1,2,4-Triazolo[5′,1′: 2,3]pyrimido[4,5-b]azepineThe 2-amino-1-tosyl-Δ2-pyrroline enamino esters 2a, b react with dichlorotriphenylphosphorane to give the iminophosphoranes 3a, b. With acetylenic esters (4a-c) the 6,7-dihydro-1H-azepines 6a-d are formed according to the cycloaddition-ring enlargement principle. Acids hydrolyze to afford the free azepine enamino esters 7a, c, d. With phenyl isocyanate 6a gives the carbodiimide 9, which upon treatment with 5% aq. NaOH cyclizes to give the pyrimido[4,5-b]azepine 10. Analogously, isopropylamine and hydrazine lead to the 2-N-substituted bicycles 11a, b; with triethyl orthoformiate 11a yields the novel 5:6:7-tricycle 13.
    Notes: Die 2-Amino-1-tosyl-Δ2-pyrrolin-enaminoester 2a, b reagieren mit Dichlortriphenylphosphoran zu den Iminophosphoranen 3a, b. Mit Acetylenestern (4a-c) entstehen nach dem Prinzip Cycloaddition-Ringerweiterung die 6,7-Dihydro-1H-azepine 6a-d. Säuren hydrolysieren zu den freien Azepin-enaminoestern 7a, c, d. Mit Phenylisocyanat ergibt 6a das Carbodiimid 9, das sich mit 5proz. Natronlauge zum Pyrimido[4,5-b]azepin 10 ringschließen läßt; Isopropylamin und Hydrazin führt analog zu den 2-N-substituierten Bicyclen 11a, b, 11a ergibt mit Orthoameisensäure-triethylester den neuen 5:6:7-Tricyclus 13.
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    Carbonylvanadate(-I) mit ungesättigten Liganden: 51V-NMR-und IR-spektroskopische Charakterisierung der Tieftemperaturspezies [V(CO)5L]-; L = N2, Alkin, Alken, CS2 und SO2 (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 895-904 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Carbonylvanadates(-I) Containing Unsaturated Ligands:51V NMR and IR Characterization of Low-temperature [V(CO)5L]- Complexes; L = N2, Alkyne, Alkene, CS2, and SO2UV irradiation of [Et4N]V(CO)6 + L in THF (L = alkyne, alkene) or 2-Me-THF (L = N2) at 200 K yields the pentacarbonylvanadates [V(CO)5L]- with end-on (N2) and side-on (alkynes, alkenes) coordinated ligands, respectively. [V(CO)5SO2]- (η1S) and [V(CO)5CS2]- (η2-C,S) were obtained from the reaction between [V(CO)5THF]- and L at 200 K. The N2 complex is also formed from [V(CO)5OCMe2]- and N2. The complexes are characterized by their IR and 51V NMR spectra. Shielding of the 51V nucleus decreases in the order alkene 〉 alkyne ≍ N2 〉 SO2 〉 CS2 〉 {O}. Compared to η1-coordination, η2-coordination gives rise to a deshielding contribution of 110 to 280 ppm. The compounds decompose at temperatures above 225 K (L = N2, 2-pentyne, 3-hexyne, cyclopentene, cyclohexene), 240 - 250 K (SO2, CS2, 1-pentene), or 285 K (1-hexyne); with PPh3, [V(CO)5PPh3]- is formed.
    Notes: Die UV-Bestrahlung von [Et4N][V(CO)6] + L in THF (L = Alkin, Alken) oder 2-Me THF (L = N2) bei 200 K führt zu Pentacarbonylvanadaten [V(CO)5L]- mit end-on (N2) bzw. side-on (Alkine, Alkene) gebundenen Liganden. [V(CO)5SO2]- (η1-S und [V(CO)5CS2]- (η2C,S) wurden durch Umsetzung von [V(CO)5THF]- mit L bei 200 K erhalten. Der N2-Komplex entsteht auch aus [V(CO)5OCMe2]- und N2. Die Komplexe werden durch ihre IR- und 51V-NMR-Spektren charakterisiert. Die Abschirmung am Kern 51V nimmt in der Reihe Alken 〉 Alkin ≍ N2 〉 SO2 〉 CS2 〉 {O} ab. Die η2-Koordination liefert gegenüber der η1-Koordination einen Entschirmugsbeitrag von 110 - 280 ppm. Die Verbindungen zersetzen sich bei Temperaturen oberhalb 225 K (L = N2, 2-Pentin, 3-Hexin, Cyclopenten, Cyclohexen), 240 - 250 K (SO2, CS2, 1-Penten) bzw. 285 K (1-Hexin); mit PPh3 erfolgt Umsetzung zu [V(CO)5PPh3]-.
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    (Trifluormethyl)selen(VI)-Verbindungen, Synthese und Eigenschaften von Tetrafluor(trifluormethyl)selen-halogeniden sowie Trifluormethanselenonaten (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 943-951 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: (Trifluoromethyl)selenium(VI) Compounds, Synthesis and Properties of Tetrafluoro(trifluoromethyl)selenium Halides and TrifluoromethaneselenonatesFluorination of CF3SeF3 with liquid F2 or AgF2 leads to CF3SeF5, which decomposes to CF4 and SeF4. With water CF4 and SeOF2 are formed. Addition of ClF to CF3SeF3 gives CF3SeF4Cl, which splits mainly into CF3Cl and SeF4. Hydrolysis provides analogously CF3Cl and SeOF2. A neutral concentrated solution of KMnO4 oxydizes CF3SeO2H in water in good yields to CF3SeO3K, the free acid of which is obtained with 74% HClO4. The aqueous solution can be concentrated up to 90%, but above this concentration spontaneous decomposition to CF4, COF2, and SeO2 occurs. Trifluoromethaneselenonates are stable at room temperature but decompose when heated.
    Notes: Die Fluorierung von CF3SeF3 mit flüssigem Fluor bzw. AgF2 führt zu CF3SeF5 das thermisch in CF4 sowie SeF4 zerfällt und mit H2O zu CF4 und SeOF2 hydrolysiert. Durch Addition von ClF an CF3SeF3 entsteht CF3SeF4Cl, das sich hauptsächlich zu CF3Cl und SeF4 zersetzt. Die Hydrolyse liefert analog CF3Cl und SeOF2. Mit wäßr., gesättigter KMnO4 liefert CF3SeO2H in guter Ausbeute CF3SeO3K, aus dem die freie Säure mit 74proz. HClO4 erhalten wird. Sie läßt sich in wäßriger Lösung bis zu 90% anreichern und zerfällt bei weiterem Konzentrieren spontan zu CF4, COF2 und SeO2. Ihre Salze sind bei Raumtemperatur stabil und explodieren beim Erhitzen.
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    Metallkomplexe mit biologisch wichtigen Liganden, XXXIV. Allyl-Palladium(II)- und Triphenylphosphan-Gold(I)-Komplexe mit Nucleobasen und Nucleosiden (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 931-942 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metal Complexes with Biologically Important Ligands, XXXIV. Allyl-Palladium(II) and Triphenylphosphane Gold(I) Complexes with Nucleobases and NucleosidesThe reactions of (η3-allyl)Pd(μ-Cl)2Pd(η3-allyl) (A) and (COD)Rh(μ-Cl)2Rh(COD) with nucleobases and nucleosides give the complexes (η3-C3H5)Pd(L)Cl (1) (L = inosine, adenosine, guanosine, cytosine, cytidine, 2-thiouracil, 2-thiocytosine) and (COD)Rh(cytosine)Cl (2), respectively. With adenosine and purine also ligand bridged complexes (η3-C3H5)(Cl)Pd—L—Pd(Cl)(η3-C3H5) (3) have been obtained. Ph3PAuCl reacts with the anions L′ of purine, adenine, uridine, and inosine to give the complexes Ph3PAuL′ (5). Ph3PAu+ is added to both N atoms of the dianion of uracil with formation of 6. The coordination of the nucleobases is discussed on the basis of the 1H and 13C NMR spectra. The X-ray structure of Ph3PAu(adeninate) (5b) has been determined.
    Notes: Die Umsetzung von (η3-Allyl)Pd(μ-Cl)2Pd(η3-Allyl) (A) sowie von (COD)Rh(μ-Cl)2Rh(COD) mit Nucleobasen und Nucleosiden liefert unter Spaltung der Chlorobrücken die Komplexe (η3C3H5)-Pd(L)Cl (1) (L = Inosin, Adenosin, Guanosin, Cytosin, Cytidin, 2-Thiouracil, 2-Thiocytosin) bzw. (COD)Rh(Cytosin)Cl (2). Mit Adenosin und Purin wurden auch Ligand-verbrückte Komplexe (η3-C3H5)(Cl)Pd—L—Pd(Cl)(η3-C3H5) (3) erhalten. Ph3PAuCl setzt sich mit den Anionen L′ von Purin, Adenin, Uridin und Inosin zu Ph3PAuL′ (5) um; Ph3PAu+ addiert sich an die beiden N-Atome des Dianions von Uracil unter Bildung von 6. Die Koordination der Nucleobasen wird anhand der 1H- und 13C-NMR-Spektren diskutiert. Die Struktur von Ph3PAu (Adeninat) (5b) wurde röntgenographisch bestimmt.
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    Bicyclofulvene, XI. Zur Frage der Spirokonjugation bei Spiro[cycloheptatrien-7,7′-norbornadien] (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1000-1007 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bicyclofulvenes, XI. On the Question of Spiroconjugation in Spiro[cycloheptatriene-7,7′-norbornadiene]The title compound 4 as well as the derivatives 5 und 6 have been prepared. The first band in the UV spectrum of 4 in n-heptane is blue-shifted by ca. 20 nm with respect to those of 5 and 6. Model calculations with the CNDO/S-CI method indicate that this hypsochromic shift as well as the bathochromic shift of the corresponding band of 2 relative to that of 3, cannot be explained by spiroconjugation. The thermolysis of 4 yields benzene, heptafulvalene (15), and fulveneallene (16). The latter products are probably derived from cycloheptatrienylidene (14) as an intermediate.
    Notes: Die Titelverbindung 4 sowie die Derivate 5 und 6 wurden dargestellt. Die erste Bande im UV-Spektrum von 4 in n-Heptan zeigt eine hypsochrome Verschiebung um ca. 20 nm verglichen mit den Banden in 5 und 6. Modellrechungen mit der CNDO/S-CI-Methode zeigen, daß, sowohl diese hypsochrome Verschiebung als auch die bathochrome Verschiebung der entsprechenden Bande von 2 im Vergleich zu 3 nicht auf Spirokonjugation beruht. Die Thermolyse von 4 ergibt neben Benzol Heptafulvalen (15) und Fulvenallen (16). Diese Produkte machen eine Spaltung von 4 in Benzol und Cycloheptatrienyliden (14) wahrscheinlich.
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    Neue Reagenzien, XXXII. Alkyldiphenylbismutane: Synthese, Eigenschaften und Halogenolyse (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1031-1038 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Reagents, XXXII. Alkyldiphenylbismutanes: Synthesis, Properties, and HalogenolysisAlkyldiphenylbismutanes 1 have been synthesized for the first time (61-92%). These compounds are air sensitive, not spontaneously inflammable liquids which decompose not below ≍ 170°C. The diphenylbismutino group is a very good equivalent for Cl- or Br-substituents at aliphatic residues since halogenolysis of the Bi-Alk bond with SO2Cl2 or Br2 already occurs at -40 to 0°C (corresponding fissions of As-Alk and Sb-Alk bonds afford heating to ≍ 130 or ≍ 220°C).
    Notes: Erstmals konnten Alkyldiphenylbismutane 1 synthetisiert werden (61-92%). Es sind luftempfindliche, nicht selbstentzündliche Flüssigkeiten, die sich erst bei ≍ 170°C zersetzen. Die Diphenylbismutino-Gruppe ist ein sehr gutes Äquivalent für aliphatisch gebundenes Chlor oder Brom, da die Halogenolyse der Bi-Alk-Bindung mit SO2Cl2 oder Br2 bereits bei - 40 bis 0°C abläuft (entsprechende Spaltungen von As-Alk- und Sb-Alk-Bindungen erfolgen bei ≍ 130 bzw. ≍ 220°C).
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    Dimere Phospha- und Thiastannylene: Ylidartige Diphospha- und Dithiadistannetane (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1045-1049 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Dimeric Phospha- and Thiastannylenes: Ylide-type Diphospha- and DithiadistannetanesBis(di-tert-butylphosphino)tin(II) (1) is obtained from the reaction of potassium di-tert-butyl-phosphide with stannous chloride or with the stannous chloride-triethylphosphane complex. Bis(tert-butylthio)tin(II) (2) is prepared by reaction of (η5-C5H5)2Sn with 2-methyl-2-propanethiol or from stannous chloride and (tert-butylthio)trimethylsilane. In solution, 1 and 2 are PR2-and SR-bridged dimers, respectively. NMR spectra indicate that rapid scrambling of terminal and bridging substituents occurs in 2 but not in the cyclic \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm P}\limits^ + - \mathop {\rm S}\limits^{\rm - } {\rm n} $\end{document} ylide 1.
    Notes: Bis(di-tert-butylphosphino)zinn(II) (1) entsteht durch Reaktion von Kalium-di-tert-butylphos-phid mit Zinndichlorid oder dem Zinndichlorid-Triethylphosphan-Komplex. Bis(tert-butylthio)-zinn(II) (2) wird hergestellt durch Umsetzung von (η5-C5H5)2Sn mit 2-Methyl-2-propanthiol und entsteht auch bei der Reaktion von Zinndichlorid mit (tert-Butylthio)trimethylsilan. 1 und 2 liegen in Lösung als PR2- bzw. SR-verbrückte Dimere vor. Kernresonanzspektren zeigen, daß bei dem cyclischen \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm P}\limits^ + - \mathop {\rm S}\limits^{\rm - } {\rm n} $\end{document}-Ylid 1 im Gegensatz zu 2 auch in Ethern keine raschen Platzwechselvorgänge (Brücke/terminal) ablaufen.
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    Regioselektive Addition von Grignard-Reagenzien an 3-Methoxy- und 3-Nitrophthalsäureanhydrid (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1058-1070 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Regioselective Addition of Grignard Reagents to 3-Methoxy- and 3-Nitrophthalic AnhydrideThe regioselectivity in the addition of the grignard reagents 5a and 6a to the anhydrides 1 and 2 is determined by the solvent system: in a highly selective manner (3: 97), the meta carbonyl group is attacked in tetrahydrofuran/tetramethylethylenediamine, while predominant, but relatively unselective (maximum 78:22) addition to the ortho carbonyl group is observed in diethyl ether. The influence of the solvent system on the regioselectivity is discussed. The LUMO-coefficients of the carbonyl carbon atoms in 1 and 2 were calculated.
    Notes: Die Addition der Grignard-Reagenzien 5a und 6a an die Anhydride 1 und 2 wird entscheidend vom Reaktionsmedium beeinflußt: in Tetrathydrofuran/Tetramethylethylendiamin wird hochselektiv (3: 97) die meta-ständige, in Diethylether dagegen überwiegend, aber mit nur geringer Selektivität (maximal 78: 22), die ortho-Carbonylgruppe angegriffen. Die Strukturen der dabei erhaltenen Addukte werden durch Umwandlung in die Ester 7-10, in die Lactone 11 sowie in die Ketone 12 und 13 bewiesen. Im Zusammenhang mit dem Versuch, die lösungsmittelabhängige Regioselektivität zu interpretieren, wurden die LUMO-Koeffizienten der Carbonylkohlenstoff-atome in 1 und 2 berechnet.
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    Cyanphosphorverbindungen, 8. Das ungewöhnliche Anion P2C10N102- (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1078-1085 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyanophosphorus Compounds, 8. The Unusual Anion P2C10N102-The reaction P(CN)3 + CN- (as [18]crown-6-sodium salt) leads via the spectroscopically identified P(CN)4 - to a disproportionation PIII → PI + PV. P(CN)2 - and P2C10N102- (1) have been isolated as products (with Ph3PCHPPh3 + as counter ion). In the latter an anionic aminomalononitrile bridge connects a dicyanophosphino and a pentacyanophosphate group, -P(CN)2 and - P(CN)5-, respectively.
    Notes: Die Reaktion P(CN)3 + CN- (als [18]Krone-6-Natriumsalz) führt über das nur spektroskopisch erkennbare P(CN)4- zur Disproportionierung PIII → PI + PV. Als Produkte können (mit Ph3PCHPPh3 + als Kation) P(CN)2- und P2C10N102- (1) gefaßt werden. In letzterem sind ein Dicyanphosphino-und ein Pentacyanophosphatrest, -P(CN)2 bzw. - P(CN)5-, über eine anionische Aminomalononitrilbrücke miteinander verbunden.
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    Addition von Aldehyden an aktivierte Doppelbindungen, XXXV. α-Ketosäuren als Äquivalent für Aldehyde in der Thiazoliumsalz-katalysierten Addition (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1115-1125 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Addition of Aldehydes to Activated Double Bonds, XXXV. α-Keto Acids as an Equivalent for Aldehydes in the Thiazolium Salt-Catalyzed Additionα-Keto acids can be used instead of aldehydes in the thiazolium salt-catalyzed addition to vinyl ketones. The yields of γ-diketones 1-7 resulting from the aliphatic α-keto acids are equivalent with those obtained from the aldehydes. The diketo acids 9-19 are prepared from the easily accessible 2-oxodiacids. Phenylpyruvic acids are easier to prepare than the phenylacetalehydes and give better yields compared with the corresponding aldehydes in the addition to vinyl ketones leading to the γ-diketones 20-29. These diketones are converted to cyclopentenones. The dihydrofurylglyoxylic ester 40 leads to the diketone 43, which is converted to the diketone 44. There is no aldehyde known equivalent to that keto acid.
    Notes: α-Ketosäuren können anstelle von Aldehyden in die Thiazoliumsalz-katalysierte Addition an Vinylketone eingesetzt werden. So entstehen die γ-Diketone 1-7 aus den α-Ketosäuren der aliphatischen Reihe in Ausbeuten, die der Aldehydaddition entsprechen. Aus den gut zugänglichen 2-Oxodisäuren werden die Diketosäuren 9-19 erhalten. Phenylbrenztraubensäuren sind besser als Phenylacetaldehyde zu synthetisieren und liefern in der Addition an Vinylketone zu den γ-Diketonen 20-29 bessere Ausbeuten. Diese Diketone wurden in Cyclopentenone übergeführt. Aus dem Dihydrofurylglyoxylsäure-ethylester 40 kann das Diketon 43 und daraus das Diketon 44, erhalten werden, ein entsprechender Aldehyd ist nicht bekannt.
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    Masthead (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985) 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    URL: http://dx.doi.org/10.1002/cber.19851180501
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    Heterocyclische 8π-Systeme, 16. Eliminierung an 2-Alkoxy-3-hydroxyindolinen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1726-1731 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterocyclic 8π-Systems, 16. Elimination Reactions of 2-Alkoxy-3-hydroxyindolinesThermolysis of 2-ethoxy-3-hydroxyindolines 1a-f affords oxindoles 3a-f as main products and the corresponding 3-indolinones 2a-f as by-products. The reaction course via indole 2,3-oxide intermediates is discussed. For this reason rearrangement reactions of 3-hydroxyindoleninium salts 4a, f are investigated.
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    Chirale Lactole, IV. Selektivitäten bei Acetalisierungsreaktionen enantiomerenreiner Lactole am Beispiel von Octahydro-8,9,9-trimethyl-5,8-methano-2H-1-benzopyran-2-ol (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1733-1745 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Chiral Lactols, IV. Selectivities in Acetal Formation Reactions of Enantiomerically Pure Lactols using Octahydro-8,9,9-trimethyl-5,8-methano-2H-1-benzopyran-2-ol as a ModelA synthesis of the lactol 1 is described and its application as a reagent for the resolution of racemates is demonstrated in several examples. By means of X-ray and conformation analysis a general rule is given, which allows to predict the absolute configuration of acyclic alkyl-aryl-carbinols from the course of acetal formation between an enantiomerically pure lactol and the racemic alcohol.
    Notes: Eine Synthese für das Lactol 1 wird beschrieben und seine Eignung als Reagens zur Racemattrennung an einigen Beispielen gezeigt. Aufgrund einer Röntgenstruktur und konformationsanalytischer Überlegungen wird eine allgemeine Regel erarbeitet, nach welcher die Absolutkonfiguration acyclischer Alkyl-aryl-carbinole aus dem Verlauf der Acetalisierungsreaktion eines enantiomerenreinen Lactols mit dem racemischen Alkohol vorhergesagt werden kann.
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    Aufbau Germylidin-verbrückter Drei- und Vierkerncluster (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1746-1757 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Buildup of Germylidyne-bridged Tri- and Tetranuclear ClustersReaction of organogermanium trihalides with KCo(CO)4 yields the trinuclear clusters RGeCo3(CO)9 (1, R = Me, Ph, tBu) as well as the new tetranuclear clusters (RGe)2Co4(CO)11 (3, R = Ph, tBu). The dinuclear complexes LnM — GeI2 — MLn (4-6, = FeCp(CO)2, Co(CO)4, NiCpCO) resulting from insertion of GeI2 into metal-metal bonds react with KCo(CO)4 to form the clusters LnM — GeCO3(CO)9 (7-9). Metal exchange reactions produce the hetero tetranuclear clusters (tBuGe)2Co3(CO)8M′Ln = MoCp(CO)2, NiCp). Crystal structure analyses were performed for Cp(CO)2Fe — GeCo3(CO)9 (7) and (tBuGe)2Co3(CO)8NiCp (11).
    Notes: Die Umsetzung von Organogermaniumtrihalogeniden mit KCo(CO)4 liefert sowohl die Dreikerncluster RGeCo3(CO)9 (1, R = Me, Ph, tBu) als auch die neuen Vierkerncluster (RGe)2Co4(CO)11 (3, R = Ph, tBu). Die durch Insertion von Gel2 in Metall-Metall-Bindungen entstehenden Zweikernkomplexe LnM — GeI2 — MLn (4-6, MLn = FeCp(CO)2, Co(CO)4, NiCpCO) setzen sich mit KCo(CO)4 zu den Clustern LnM — GeCO3(CO)9 (7-9) um. Metallaustauschreaktionen liefern die Heterovierkerncluster (tBuGe)2Co3(CO)8M′Ln (10, 11, M′Ln = MoCp(CO)2, NiCp). Von Cp(CO)2Fe — GeCo3(CO)9 (7) und (tBuGe)2Co3(CO)8NiCp (11) wurden Kristallstrukturanalysen durchgeführt.
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    1,3-Dithienium- und 1,3-Dithioleniumsalze, II. Synthese monocyclothioacetalisierter 1,3-Diketone aus Silylenolethern (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1798-1808 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,3-Dithienium- and 1,3-Dithiolenium Salts, II. Synthesis of Monocyclothioacetalized 1,3-Diketones from Silyl Enol EthersThe 1,3-dithienium and 1,3-dithiolenium salts 3, available from the dithiols 1 or the cyclic thioacetals 4 (n = 2, 3) by reaction with the acyl chlorides 2, trityl tetrafluoroborate (5), and sulfuryl chloride (7), react in good yields with the silyl enol ethers 10 to give the new monocyclothioacetalized 1,3-Diketones 11. The synthetic of 11 as partially protected 1,3-Diketones is demonstrated exemplarily by dethioacetalization to the 1,3-dicarbonyl compounds 13.
    Notes: Die aus den Dithiolen 1 oder den cyclischen Thioacetalen 4 (n = 2, 3) durch Umsetzung mit den Acylchloriden 2, Trityl-tetrafluoroborat (5) und Sulfurylchlorid (7) erhältlichen 1,3-Dithienium-bzw. 1,3-Dithioleniumsalze 3 reagieren in guten Ausbeuten mit den Silylenolethern 10 zu den neuen monocyclothioacetalisierten 1,3-Diketonen 11. Das synthetische Potential von 11 als partiell geschützten 1,3-Diketonen wird exemplarisch durch Dethioacetalisierung zu den 1,3-Dicarbonylverbindungen 13 demonstriert.
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    Syntheses and ENDOR studies of selectively deuterated galvinoxyl radicals. Complete Determination of the 13C hyperfine coupling constants of Coppinger's radical (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1782-1797 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesen und ENDOR-Untersuchungen selektiv deuterierter Galvinoxyl-Radikale. Vollständige Bestimmung der 13C-Hyperfeinkopplungskonstanten von Coppingers RadikalDie Synthese einiger selektiv deuterierter Galvinole und deren Oxidation zu den korrespondierenden Galvinoxyl-Radikalen, z.B. Coppingers Radikal und Yangs Biradikal, wird beschrieben. Am Beispiel der Dublettradikale wird gezeigt, daß 13C-ENDOR-Spektroskopie auch ohne 13C-Isotopenanreicherung möglich ist. Im Falle von Coppingers Radikal gelang die vollständige Ermittlung der 13C-Hyperfeinkopplungskonstanten. Die ENDOR-Untersuchung von selektiv deuteriertem Yangs Biradikal in glasartiger Matrix erlaubte eine eindeutige Zuordnung der Singale zu Molekülpositionen, und es ließen sich Rückschlüsse auf die Radikalsymmetrie und die behinderte Rotation der tert-Butylgruppen ziehen. In den ENDOR-Spektren regellos orientierter Bisgalvinoxyl-Biradikale im Triplettzustand findet man scharfe Signale bei den freien Kern-Zeeman-Frequenzen, die von NMR-Übergängen im Ms = 0-Spinzustand herrühren. Es wird gezeigt, daß die betreffenden Deuterium-Signale infolge der Quadrupolwechselwirkung der Deuteriumkerne aufgespalten sind.
    Notes: The synthesis of selectively deuterated galvinols is described. Oxidation results in the formation of the respective galvinoxyl free radicals, e.g., Coppinger's radical and Yang's biradical. It is shown that 13C ENDOR signals can be detected for the doublet radicals without 13C labelling, i.e., in natural abundance. The complete set of 13C hyperfine coupling constants of Coppinger's radical could be determined. The ENDOR study of selectively deuterated Yang's biradical in a glassy matrix allowed an unambiguous assignment of the signals to molecular positions, and conclusions with respect to the symmetry of the radical and the hindered rotation of the tert-butyl groups could be drawn. Randomly oriented bisgalvinoxyl biradicals in the triplet spin state give rise to sharp ENDOR lines at the free nuclear Zeeman frequencies due to NMR transitions in the Ms = 0 electron spin manifold, and it is demonstrated that the respective 2H ENDOR lines show quadrupole splittings.
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    Darstellung von (η6-Aren)2Cr2(CO)3-Komplexen mit einer formalen Cr ≡ Cr-Dreifachbindung aus η6-ArenCr(CO)2NCCH3 (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1825-1835 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of (η6-arene)2Cr2(CO)3 Complexes Containing a Formal Cr ≡ Cr Triple Bond Starting from η6-areneCr(CO)2NCCH3The photochemical reaction of η6-ArCr(CO)3 (Ar = benzene, toluene, m-xylene, mesitylene, methyl benzoate, and fluorobenzene) with acetonitrile in hexane or p-tolunitrile in THF, resp., yields complexes η6-ArCr(CO)2NCR (1 - 10). Solutions of the red acetonitrile complexes yield on warming or UV photolysis by dissoziation of the nitrile and one CO ligand in the presence of benzene the new black coordination compounds (η6-Ar)2Cr2(CO)3 (11 - 16). The spectra and an X-ray structure determination of the benzene derivative 11 verify a Cr2-unit with a formal triple bond bridged by three CO ligands. The asymmetric unit of 11 contains two halves of molecules with Cr — Cr distances of 222.6 and 221.6 pm.
    Notes: Bei der photochemischen Umsetzung von η6-ArCr(CO)3 (Ar = Benzol, Toluol, m-Xylol, Mesitylen, Benzoesäure-methylester und Fluorbenzol) mit Acetonitril in Hexan bzw. p-Tolunitril in THF entstehen Komplexe η6-ArCr(CO)2NCR (1-10). Lösungen der roten Acetonitrilkomplexe bilden in der Wärme oder bei UV-Bestrahlung unter Abspaltung des Nitril- und eines CO-Liganden in Gegenwart von Benzol die neuen schwarzen Komplexe (η6-Ar)2Cr2(CO)3 (11-16). Die Spektren und die Röntgenstrukturanalyse des Benzolderivats 11 belegen eine von drei CO-Liganden verbrückte, formal eine Dreifachbindung aufweisende Cr2-Einheit. Die asymmetrische Enheit von 11 enthält zwei Molekülhälften mit Cr — Cr-Abständen von 222.6 bzw. 221.6 pm.
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    Reaction of 1-oxa-3-azabutatrienium salts with tertiary carboxamides (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1876-1886 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktion von 1-Oxa-3-azabutatrienium-Salzen mit tertiären CarbonsäureamidenDie α-Chlorisocyanate 1 reagieren mit tertiären Carbonsäureamiden oder Acyliminen 3 in Gegenwart von Lewis-Säuren (SbCl5, FeCl3) unter milden Bedingungen zu den aminosubstituierten 2-Azaallenium-Salzen 5a - t. Die nur mäßig starken Elektrophile 5 setzen sich mit Methanol zu den Acetalen 8 und 10 um. Eine Röntgenstrukturanlyse von 5a zeigt, daß die -Einheit dieses Moleküls gewinkelt ist (128°). Es besteht eine Proportionalität zwischen der Wellenzahl der antisymmetrischen Valenzschwingung von 2-Azaallenium-Salzen und dem -Bindungswinkel. Die durch die sp2-Kohlenstoffe der -Einheit von 5a definierten Ebenen stehen nahezu senkrecht (84°) aufeinander.
    Notes: α-Chloro isocyanates 1 react with tertiary carboxamides or acylimines 3 in the presence of Lewis acids (SbCl5, FeCl3) to give the amino-substituted 2-azaallenium salts 5a - t under mild conditions. With methanol the moderately strong electrophiles 5 afford the acetals 8 and 10. According to an X-ray structural analysis, the C = N = C unit of 5a is bent by 128°. There exists a linear relationship between the wave number of the antisymmetric stretching vibration of 2-azaallenium salts and the bond angle. The planes defined by the sp2 carbons of the moiety of 5a are almost perpendicular (84°) with respect to each other.
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    Bildung von Oxetanen bei der photosensibilisierten Oxidation von Enaminen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1927-1935 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Formation of Oxetanes via Photo-sensitized Oxidation of EnaminesPhotooxidations of the enamines 1 and 5 in toluene give rise to the formation of the usual reaction products. In methanol, however, the oxetanes 8 and 13, respectively, are isolated as the main photooxidation products. Both the mechanism of their formation as well as some reactions of 8 and 13 are discussed. Oxidation of 13 with m-chloroperbenzoic acid produces the aldehyde 15 via a multi-step reaction.
    Notes: Die Photooxidation der Enamine 1 bzw. 5 in Toluol liefert die erwarteten Reaktionsprodukte. In Methanol entstehen dagegen die Oxetane 8 bzw. 13 als Hauptprodukt der Photooxidation. Die Reaktionen dieser Verbindungen werden beschrieben. Die Oxidation von 13 mit m-Chlorperbenzoesäure führt über einen mehrstufigen einheitlichen Reaktionsablauf zum Aldehyd 15. Der Bildungsmechanismus der Oxetane 8 und 13 wird diskutiert.
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    Die Elektronenstruktur von 1,4-disubstituierten Butantetronen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1917-1926 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Electronic Structure of 1,4-Disubstituted ButanetetronesThe He(I) photoelectron (PE) spectra of the disubstituted butanetetrones 1 a - e have been recorded. The assignment of the first PE bands is based on semiempirical calculations. For 1 a - e the first bands could be assigned to ionization events from lone pair combinations on the oxygen atoms and in the case of 1 b - e additionally to ionizations from π-orbitals localized on the aromatic rings. The comparison between the PE bands of 1 d, 1,3-diphenyl-1,2,3-propanetrione, benzil, and benzophenone yields the result that the energy split between the n-orbital energies con-verges towards a value of about 3 eV. The interactions among the lone pairs and between lone pairs and the σ frame in 2 b - d are discussed, based on INDO calculations using localized orbitals.
    Notes: Die He(I)-Photoelektronen(PE)-Spektren der 1,4-disubstituierten Butantetrone 1 a - e wurden gemessen und anhand semiempirischer Rechnungen zugeordnet. Bei 1 a - e wurden die ersten Banden Ionisationen aus Linearkombinationen der einsamen Elektronenpaare an den Sauerstoffen und im Fall von 1 b - e noch zusätzlich Ionisationen aus den aromatischen π-Orbitalen zugeordnet. Der Vergleich zwischen den PE-Banden von 1 d, 1,3-Diphenyl-1,2,3-propantrion, Benzil und Benzophenon zeigt, daß die Aufspaltung zwischen den n-Orbitalenergien einem Grenzwert von etwa 3 eV zustrebt. Die Wechselwirkung zwischen den n-Orbitalen, den n-Orbitalen und dem σ-Gerüst (Through-Space- und Through-Bond-Wechselwirkung) in den vic. Di-, Tri- und Tetra-ketonen 2 b - d wird anhand von lokalisierten Orbitalen, die nach der INDO-Methode erhalten werden, diskutiert.
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    Azaborolinyl-Komplexe, XVI. Synthese und Untersuchung von (1,2-Azaborolinyl)tricarbonyl-Komplexen des Chroms, Molybdäns und Wolframs (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1949-1958 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Azaborolinyl Complexes, XVI. Synthesis and Investigation of (1,2-Azaborolinyl)tricarbonyl Complexes of Chromium, Molybdenum, and Tungsten1-tert-Butyl-2-methyl-1,2-azaborolinyllithium reacts with the hexacarbonyls of chromium, molybdenum, and tungsten to give the complex salts Li[(Ab)M(CO)3] (Ab = azaborolinyl ligand, M = Cr (2), Mo (3), and W (4)). With Me3ECl (E = Ge, Sn, Pb) they form the corresponding germyl, stannyl, and plumbyl derivatives. The molecular and crystal structures of (Ab)(CO)3Cr—SnMe3 (2b) and (Ab)(CO)3Mo—SnMe3 (3b) show the azaborolinyl rings to be pentahapto-bonded, inspite of a small folding of the rings, leading to a longer distance of the boron atoms to the metal atoms. The IR, 1H, 11B, and 13C NMR data prove equivalent structures for the other complexes. The existence of enantiomers in the cell results from the crystal structure investigations of 2b and 3b and is caused by the prochiral character of the azaborolinyl rings.
    Notes: 1-tert-Butyl-2-methyl-1,2-azaborolinyllithium reagiert mit den Hexacarbonylen von Chrom, Molybdän und Wolfram zu den komplexen Salzen Li[(Ab)M(CO)3] (Ab = Azaborolinyl-Ligand, M = Cr (2), Mo (3) und W (4)). Diese bilden mit Me3ECl (E = Ge, Sn, Pb) die entsprechenden Germyl-, Stannyl- und Plumbylderivate. Die Molekül- und Kristallstrukturen von (Ab)(CO)3Cr—SnMe3 und (2b) und (Ab)(CO)3Mo—SnMe3 (3b) weisen die Azaborolinylringe als pentahapto-gebunden aus, trotz einer leichten Faltung der Ringe, durch die die Boratome einen größeren Abstand zu den Metallatomen erreichen. Die IR-, 1H-, 11B- und 13C-NMR-Daten beweisen äquivalente Strukturen für die übrigen Komplexe. Aus den Kristallstrukturuntersuchungen von 2b und 3b geht die Anwesenheit von Enantiomeren in der Zelle hervor, verursacht durch den prochiralen Charakter der Azaborolinylringe.
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    2,4-Diazabicyclo[3.3.1]nonan-Gerüste aus cis-Benzoltrioxid (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2044-2078 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 2,4-Diazabicyclo[3.3.1]nonane Skeletons from cis-Benzene TrioxideBy treating cis-benzene trioxide (1) with guanidine in buffered tert-butyl alcohol solution the 1:1-adducts DL-(1α,2β,4β,5α,6α,10α)- 8-imino-3-oxa-7,9-diazatricyclo[4.3.1.02,4]decane-5,10-diol (13a) and DL-(1α,2α,3β,5β,6α,7α)- 9-imino-4-oxa-8,10-diazatricyclo[5.3.0.03,5]decane-2,6-diol (12a) resulting from 1,3(1,2)-bridging in 1 are obtained in 88 - 91% (9 - 12%) yields. Trifluoroacetamidine (acetamidine) is also selectively 1,3-added to 1. From 13a via generally regiospecific hydrolysis (26a), thiolysis (30a, d) ammonolysis (34a), hydrazinolysis (34d), and HCl-/HBr- addition (39a, c) access to highly functionalised 2,4-diazabicyclo[3.3.1]nonane derivatives is opened. During the “ring-chain tautomerism” observed for 26a and 34d (28a, 36d) the adamantoid orthocarbonic acid intermediates (27a, 35d) cannot be identified directly. The spectroscopic structure elucidations (not always unequivocal because i.a. of conformational flexibility of the skeletons) are confirmed by X-ray structural analysis for 29f, 36e, 38, und 43.
    Notes: Bei der Umsetzung von cis-Benzoltrioxid (1) mit Guanidin in gepufferter tert-Butylalkohol-Lösung werden mit 88 - 91% (9 - 12%) Ausbeute die aus der 1,3(1,2)-Überbrückung in 1 hervorgehenden 1:1-Addukte DL-(1α,2β,4β,5α,6α,10α)- 8-Imino-3-oxa-7,9-diazatricyclo[4.3.1.02,4]decan5,10-diol (13a) und DL-(1α,2α,3β,5β,6α,7α)- 9-Imino-4-oxa-8,10-diazatricyclo[5.3.0.03,5]decan-2,6-diol (12a) gewonnen. Auch Trifluoracetamidin (Acetamidin) wird an 1 bevorzugt 1,3-addiert. Aus 13a gewinnt man durch jeweils regiospezifische Hydrolyse (26a), Thiolyse (30a, d), Ammonolyse (34a), Hydrazinolyse (34d) und HCl/HBr-Addition (39a, c) Zugang zu hochfunktionalisierten 2,4-Diazabicyclo[3.3.1]nonan-Derivaten. Bei der für 26a und 34d beobachteten „Ring-Ketten-Tautomerie“ (28a, 36d) sind die adamantoiden Orthokohlensäure-Intermediate (27a, 35d) nicht nachweisbar. Die u. a. wegen der konformativen Flexibilität der Gerüste nicht immer eindeutigen spektroskopischen Strukturzuordnungen werden durch Röntgenstrukturanalysen für 29f, 36e, 38 und 43 gesichert.
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    Untersuchungen an Diazoverbindungen und Aziden, 58. Dikation-ether, 5. Formamidinium-substituierte Diazophosphoryl-Verbindungen: Synthese, Eigenschaften und Reaktionen zu Tetrazolen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2105-2117 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigations on Diazo Compounds and Azides, 58. Dication Ethers, 5. Formamidinium-substituted Diazophosphoryl Compounds: Synthesis, Properties, and Reactions Leading to TetrazolesElectrophilic diazoalkane substitution of diazophosphoryl compounds 4a - c by bis(formamidinium) ethers 3a, b leads to formamidinium-substituted (diazomethyl)phosphoryl compounds 5. These can also be considered as alkenediazonium salts, but the contribution from this resonance structure is low according to 1H NMR and IR data. Reaction of 5a - c with another equivalent of 4a - c under slightly modified conditions yields 2-vinyl-2H-tetrazoles 6 and 7. The identity of the tetrazoles has been confirmed by X-ray structure analysis of 6c as well as by thermolysis of 6c leading to pyrazole 12 which then was hydrolyzed to give the NH-pyrazole 13.
    Notes: Die Diazophosphoryl-Verbindungen 4a - c reagieren mit den Bis(formamidinium)ethern 3a, b im Sinne einer elektrophilen Diazoalkan-Substitution zu Formamidinium-substituierten (Diazomethyl)phosphoryl-Verbindungen 5. Diese lassen sich auch als Olefindiazoniumsalze auffassen, jedoch deuten 1H-NMR- und IR-Daten nur auf einen geringen Anteil dieses Bindungszustandes hin. Unter leicht modifzierten Reaktionsbedingungen reagieren 5a - c mit einem weiteren Äquivalent von 4a - c zu den 2-Vinyl-2H-tetrazolen 6 und 7. Die Identität der Tetrazole wird durch eine Röntgenstrukturanalyse von 6c sowie die Thermolyse von 6c zum Pyrazol 12 und dessen Hydrolyse zum NH-Pyrazol 13 belegt.
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    The molecular and electronic structure of dipiperidinosquaraine (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2118-2126 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molekulare und elektronische Struktur von DipiperidinoquadratainDipiperidinoquadratain (9) kristallisiert im orthorhombischen Gitter, Raumgruppe Pnab, mit 4 Molekülen in einer Elementarzelle mit den Abmessungen a = 7.1798(9), b = 9.5362(8) und c = 18.788(2) Å. Das Molekül liegt auf einem Symmetriezentrum, d.h. der Vierring (C — C = 1.456(1) Å) ist genau planar; die Stickstoff- und Sauerstoffatome sind fast mit dem Ring coplanar, mit C — O = 1.2396(7) und C — N = 1.3112(7) Å. Sowohl die experimentellen als auch die theoretischen Daten zeigen beachtliche C — N- und C — O-π-Bindungen, aber nur eine geringfügige C — C-π-Bindung im Quadratainsystem. Die Berechnungen ergeben starke 1,3-abstoßende Wechselwirkungen im Vierring. Ringfaltung, ein sonst üblicher Mechanismus bei der Vermeidung solcher Abstoßungen, wird hier durch die starke C — N-π-Bindung verhindert.
    Notes: Dipiperidinosquaraine (9) crystallizes in the orthorhombic system, space group Pnab, with four molecules in a cell of dimensions a = 7.1798(9), b = 9.5362(8), and c = 18.788(2) Å. The molecule is located over a center of symmetry, so the four-membered ring (C - C = 1.456(1) Å av) is exactly planar; the nitrogen and oxygen atoms are nearly coplanar with the ring, with C — O = 1.2396(7) and C — N = 1.3112(7) Å. Both experimental and theoretical evidence indicates the presence of considerable C — N and C — O π-bonding, but only a small amount of C — C π-bonding in the squaraine system. The calculations indicate the presence of strong 1,3-repulsive interactions within the four-membered ring. Ring puckering, which is a common mechanism to alleviate these repulsions, is prevented here by the extensive C — N π-bonding.
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    The He(Iα) PE spectra and electronic absorption spectra of hexafluorocyclobutanone and of tetrafluoro-1,2-cyclobutane-dione (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2127-2133 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Die He(Iα)-PE-Spektren und Elektronenabsorptionsspektren von Hexafluorcyclobutanon und Tetrafluor-1,2-cyclobutandionDie He(Iα)-PE-Spektren und die Elektronenabsorptionsspektren von Hexafluorcyclobutanon (3) und Tetrafluor-1,2-cyclobutandion (4) wurden gemessen. Die Zuordnung der ersten Banden beider Spektrentypen basiert hauptsächlich auf der Korrelation mit den entsprechenden Spektren der unsubstituierten Verbindungen Cyclobutanon (1) und 1,2-Cyclobutandion (2) sowie auf den Resultaten semiempirischer Rechnungen. Die Banden in den PE-Spektren von 3 und 4 werden im Vergleich zu den PE-Banden von 1 und 2 durch den Perfluor-Effekt um 1.6 bzw. 1.5 eV zu höheren Energien verschoben. Vergleicht man die Energie der ersten Bande in den Elektronenspektren von 1 und 3 bzw. 2 und 4, so findet man, daß diese Bande bathochrom um etwa 5000 cm-1 durch die Perfluor-Substitution verschoben wird. Dies wird dadurch erklärt, daß beim Ersatz der H-Atome durch F-Atome die Energie des LUMOs (π*) stärker abgesenkt wird als die des HOMOs (n).
    Notes: The He(Iα) PE and the electronic absorption spectra of hexafluorocyclobutanone (3) and tetrafluoro-1,2-cyclobutanedione (4) have been recorded. The assignment of the observed bands in both types of spectra is mainly based on the correlation with the corresponding spectra of the parent compounds cyclobutanone (1) and 1,2-cyclobutanedione (2), and in addition on the results of semiempirical calculations. As a result of the perfluoro effect, the bands in the PE spectra of 3 and 4 are shifted towards higher ionization energies by 1.6 eV and 1.5 eV relative to the corresponding bands in the PE spectra of 1 and 2. A comparison of the positions of the first band in the electronic spectra of 1 and 3, as well as of 2 and 4, shows that this band is shifted bathochromically by about 5000 cm-1 as a consequence of the perfluoro substitution. This is explained as being due to a stronger lowering of the LUMO (π*) energy than that of the HOMO (n) energy, induced by the replacement of the H-by F-atoms.
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    Cycloadditionen des 1-(4-Methoxyphenyl)-2,2-dimethylvinyl-Kations an Olefine (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2974-2992 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloadditions of 1-(4-Methoxyphenyl)-2,2-dimethylvinyl Cation to Olefins1-Bromo-1-(4-methoxyphenyl)-2-methyl-1-propene (1) reacts with cyclohexene, cycloheptene, (Z)-cyclooctene and the silver salts AgBF4, via the vinyl cation 2 by cycloaddition to form the cyclobutenes 7b-d. Cyclobutene 8 is obtained from (Z)- and (E)- and (E)-2-butene. Besides the cyclobutene derivatives, the isomeric cyclopropane compound 10d is also formed in the reaction of 1 with (Z)-cyclooctene under the same conditions, with cyclopentene only the cyclopropane derivative is formed. Copper (I) triflate-olefin complexes can be used in place of silver slats to generate the vinyl cation 2, whereby cyclobutenes 7 are formed preferably. - In contrast to vinyl bromide 1, 1-(4-methoxyphenyl)-2-methyl-1-propenyl triflate (5) reacts with cyclopentene, cyclohexene, cyloheptene, (Z)- and (E)-cyclooctene to give mostly the corresponding cyclopropane derivatives 10. The stereoisomeric cyclopropyl compounds 19 are obtained from (Z)- and (E)-2-butene. - The mechanisms of silver-catalysed and silver-free cycloaddition reactions are discussed.
    Notes: 1-Brom-1-(4-methoxyphenyl)-2-methyl-1-propen (1) reagiert mit Cyclohexen, Cyclohepten, (Z)-Cycloocten und den Silbersalzen AgBF4 bzw. AgSbF6 über das Vinylkation 2 unter Cycloaddition überwiegend zu den Cyclobutenen 7b-d. Mit (Z)- und (E)-2- Buten wird das Cyclobuten 8 erhalten. Bei der Umsetzung von 1 unter den gleichen Bedingungen entsteht mit Cyclopenten das Cyclopropanderivat 10a, mit (Z)-Cycloocten entsteht neben dem Cyclobutenderivat 7d die isomere Cyclopropanverbindung 10d. An Stelle der Silbersalze können auch Kupfer(I)-triflat-Olefin-Komplexe zur Erzeugung des Vinylkations 2 verwendet werden, wobei ebenfalls bevorzugt die Cyclobutene 7 erhalten werden. - Im Gegensatz zum Vinylbromid 1 reagiert das 1-(4-Methoxyphenyl)-2-methyl-1-propenyl-triflat (5) mit Cyclopenten, Cyclohexen, Cyclohepten und (Z)- bzw. (E)-Cycloocten überwiegend zu den entsprechenden Cyclopropanderivaten 10. Mit (Z)- und (E)-2-Buten werden die stereoisomeren Cyclopropylverbindungen 19 erhalten. - Die Mechanismen der silbersalzkatalysierten und silberfreien Cycloadditionsreaktionen werden diskutiert.
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    Basische Metalle, LVI Reaktionen von (Pentamethylcyclopentadienyl)rhodium(I)-Komplexen mit Dihalogen- und Trihalogenmethanen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3032-3040 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Basic Metals, LVI. Reactions of (Pentamethylcyclopentadienyl)rhodium(I) Complexes with Dihalo- and TrihalomethanesC5Me5Rh(CO)2 and C5Me5Rh(CO)L (L=PMe3, PMe2Ph, P(OMe)3) react with dihalo- and trihalomethanes to give (pentamethylcyclopentadienyl)rhodium complexes containing CH2X and CHX2 (X=Cl, Br, I, CN) as ligands. The reactions of [C5Me5RhCH2I(L)I] (L=CO, PMe3) with NaOCH3, PMe3, and PPh3 lead in some cases to substitution (e.g., formation of [C5Me5RhCH2OMe(PMe3)I] and [C5Me5Rh(CH2PPh3)(PMe3)I]X), in some cases to cleavage of the Rh - C bond. [C5Me5RhCH2I(CO)I] reacts with CH2(PPh2)2 to form the cyclic ylide complex [Ph2(I)]I.
    Notes: Durch Reaktion von C5Me5Rh(CO)2 und C5Me5Rh(CO)L (L=PMe3, PMe2Ph, P(OMe)3) mit Dihalogen- und Trihalogenmethanen werden (Pentamethylcyclopentadienyl)rhodium-Komplexe mit CH2X und CHX2 (X=Cl, Br, I, CN) als Liganden synthetisiert. Die Umsetzungen von [C5Me5RhCH2I(L)I] (L=CO, PMe3) mit NaOCH3, PMe3 und PPh3 verlaufen teilweise unter Substitution (Bildung z.B. von [C5Me5RhCH2OMe(PMe3)I] und [C5Me5Rh(CH2PPh3)(PMe3)I]X), teilweise aber auch unter Spaltung der Rh - C-Bindung. [C5Me5RhCH2I(CO)I] reagiert mit CH2(PPh2)2 zu dem cyclischen Yild-Komplex [Ph2(I)]I.
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    Monoozonolysen von acyclischen konjugierten Dienen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3041-3057 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Monoozonolyses of Acyclic Conjugated DienesMonoozonolyses of isoprene (1a), 2-methyl-3-phenyl-1,3-butadiene (1b), 2,3-diphenyl-1,3-butadiene (25), and 2,3,4,5-tetramethyl-2,4-hexadiene (34) have been examined in pentane and in methanol. The dienes 1a, b and 25 afforded all possible α,β-unsaturated monoozonides and α,β-unsaturated methoxy hydroperoxides, respectively, whereas diene 34 gave no ozonide and no α,β-unsaturated methoxy hydroperoxide. From the dienes 25 and 34, the corresponding monoepoxides have been formed additionally. The results allow some conclusions concerning the regioselectivity of ozone attack at the unsymmetrically substituted dienes 1a, b as well as concerning the cleavage directions of primary ozonides.
    Notes: Monoozonolysen von Isopren (1a), 2-Methyl-3-phenyl-1,3-butadien (1b), 2,3-Diphenyl-1,3-butadien (25) und 2,3,4,5-Tetramethyl-2,4-hexadien (34) in Pentan und in Methanol wurden untersucht. Die Diene 1a, b und 25 lieferten alle möglichen α,β-ungesättigten Monoozonide bzw. α,β-ungesättigten Methoxyhydroperoxide; das Dien 34 ergab kein Ozonid und kein α,β-ungesättigtes Methoxyhydroperoxid. Aus den Dienen 25 und 34 wurden zusätzlich auch die entsprechenden Monoepoxide erhalten. Die Ergebnisse erlauben Rückschlüsse auf die Regioselektivität des Ozonangriffes an den unsymmetrisch substituierten Dienen 1a, b sowie über die Spaltungsrichtungen von Primärozoniden.
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    Photolyse des 9-Azidotriptycens. - Struktur des Dimeren eines extrem gespannten Brückenkopfimins (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3058-3069 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photolysis of 9-Azidotriptycene. - Structure of the Dimer of a Severely Strained Bridgehead IminePhotolysis of 9-azidotriptycene (4) in cyclohexane affords molecular nitrogen and a dimer of the intermediate bridgehead imine 5 in 69% yield. The dimer is very sensitive towards traces of acid and irradiation in the presence of oxygen. The structure of the dimer is elucidated by spectroscopic methods as well as by an X-ray diffraction analysis. In solution approximately equal amounts of the (racemic) diastereomers 10 A and B are present which interconvert via an energy barrier of ΔG413≠ = ca. 90 kJ · mol-1. In contrast, in the crystalline state only diastereomer 10 A exists. The distereomer 10 A crystallizes as a racemate in the monoclinic space group P21/n (No. 14) with four molecules per cell. As the first step in the formation of 10 A, B we assume a dimerization of the bridgehead imine 5 producing 12 which rearranges to 10 A, B via a proton shift (→13) and subsequent opening of one of the 4H-azepine rings. The results are indicative of some diradical character of the bridgehead imine 5.
    Notes: Die Photolyse des 9-Azidotriptycens (4) in Cyclohexan ergibt neben Stickstoff mit 69% Ausbeute ein Dimeres des intermediären Brückenkopfimins 5. Das Dimere ist sehr empfindlich gegen Säurespuren und Belichten in Gegenwart von Luftsauerstoff. Die Struktur des Dimeren wird spektroskopisch und durch Röntgenbeugungsanalyse aufgeklärt. In Lösung liegen etwa gleiche Mengen der Diastereomeren 10 A und B vor, die sich mit ΔG413≠ =ca. 90 kJ · mol-1 ineinander umwandeln. Im Kristall existiert dagegen nur das Diastereomere 10 A, das als Racemat monoklin in der Raumgruppe P21/n (Nr. 14) mit vier Molekülen in der Elementarzelle kristallisiert. Als ersten Schritt der Bildung von 10 A, B nehmen wir eine Dimerisierung des Brückenkopfimins 5 zu 12 an, das sich durch Protonenwanderung (→13) und Öffnung eines 4H-Azepinrings in 10A, B umlagert. Die Ergebnisse sprechen für einen gewissen Diradikalcharakter des Brückenkopfimins 5.
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    Über sterisch gehinderte freie Radikale, XII. Das Radikal tert-Butyldiphenylmethyl, sein Dimeres sowie deren Autoxidation. Eine Neuuntersuchung (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 450-456 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sterically Hindered Free Radicals, XII. The Radical tert-Butyldiphenylmethyl, Its Dimer, and Their Autoxidation. A ReinvestigationThe radical Ph2C.  -  tBu (1) dimerizes giving reversibly the quinonoid derivative 3, and not the ethane-like 2 as reported in the literature. In equilibrium there are less radicals 1 than in the case of triphenylmethyl, ΔHdiss = 18.5 ± 2 kcal/mol for 3. Both the radical 1 and its dimer 3 are rapidly oxidized by oxygen. 1 gives the dialkyl peroxide 6 which fragmentates already at 20°C mainly to benzophenone and tBu., 3 leads to the ketone 7, probably via the hydroperoxide 10. 3 rearranges catalysed by acid and by base as well via a 1,5-hydrogen migration forming the benzenoid derivative 4. Preparative and ESR details are given.
    Notes: Das Radikal Ph2C.  -  tBu (1) dimerisiert reversibel zum chinoiden Derivat 3 und nicht zum ethan-artigen 2, wie in der Literature berichtet. Im Gleichgewicht liegt weniger Radikal 1 vor als im Fall von Triphenylmethyl, ΔHDiss = 18.5 ± 2 kcal/mol für 3. Sowohl das Radikal 1 wie sein Dimeres 3 werden durch Sauerstoff rasch oxidiert. 1 gibt das Dialkylperoxid 6, das schon bei 20°C fragmentiert, hauptsächlich zu Benzophenon und tBu., 3 führt zum Keton 7, wahrscheinlich über das Hydroperoxid 10. 3 lagert sich, sowohl säure- wie basenkatalysiert, unter 1,5-H-Verschiebung um in das benzoide Derivat 4. Einzelheiten zu den Darstellungen sowie zur ESR-Spektroskopie werden angegeben.
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    Beiträge zur Chemie des Bors, 146. Über die Reaktion von Tetrazadiborinanen mit Heterokumulenen: Pseudodipolare [2 + 3]-Cycloadditionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 483-494 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, 146 Reactions of Tetrazadiborinanes with Heterocumulenes: Pseudodipolar [2 + 3]-CycloadditionsCO2, COS, and CS2 scavenge the 1,3-dipolar unit \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm R'}\mathop {{\rm B - }}\limits^ \oplus {\rm NR - }\mathop {\rm N}\limits^{\rm \Theta } {\rm R} $\end{document} from the tetrazadiborinanes 3. [2 + 3]-Cycloadducts are formed in a pseudodipolar reaction, namely oxadiaza- and thiadiazaborolidines of type 7, 8 and 4. A reaction mechanism is suggested.  -  The thiadiazaborolidine 4b contains a planar five-membered ring according to an X-ray structure determination. Short BN, NN, and CN bond distances suggest a heteroaromatic ring system. High polarity is associated with the thioxo group. In contrast, the oxadiazaborolidinones 8a, b are in an equilibrium with their dimers in solution.
    Notes: CO2, COS und CS2 fangen aus den Tetrazadiborinanen 3e) den 1,3-Dipol \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm R'}\mathop {{\rm B - }}\limits^ \oplus {\rm NR - }\mathop {\rm N}\limits^{\rm \Theta } {\rm R} $\end{document} ab. In einer pseudodipolaren Reaktion bilden sich als [2 + 3]-Cycloaddukte die Oxadiaza- und Thiadiazaborolidine 7, 8 und 4. Ein Reaktionsmechanismus wird diskutiert.  -  Nach Röntgenstrukturanalyse enthält 4b einen planaren Fünfring. Kurze BN-, NN- und CN-Abstände legen ein heteroaromatisches System nahe, wobei der Thioxo-Gruppe eine erhebliche Polarität zuzuweisen ist. Die Oxadiazaborolidinone 8a, b stehen in Lösung im Gleichgewicht mit ihrem Dimeren.
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    The colour of chelates of boron. An X-ray structural investigation of bis(4-methylphenyl)boryl and 9-borabicyclo-[3.3.1]nonyl acetylacetonates (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 670-675 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Die Farbe von Bor-Chelaten. Röntgenstruktur-Untersuchung von Bis(4-methylphenyl)boryl- und 9-Borabicyclo[3.3.1]nonyl-acetylacetonatenDie Molekülstrukturen des farblosen Bis(4-methylphenyl)boryl- und des orangefarbenen 9-Borabicyclo[3.3.1]non-9-yl-acetylacetonats (4 und 5) wurden durch Röntgenstrukturanalyse ermittelt. Die C—O-Abstände in 4 sind merklich (ca. 0.029 Å) länger als die in 5. Es wird vermutet, daß der unterschiedliche π-Charakter in den C—O-Bindungen die Verschiebungen im Elektronenspektrum der verschiedenen Chelate von 1,3-Diketonen und verwandten Verbindungen verursacht.
    Notes: The molecular structures of the colourless bis(4-methylphenyl)boryl and the orange coloured 9-borabicyclo[3.3.1]non-9-yl acetylacetonates (4 and 5, respectively) have been determined by X-ray analysis. The C—O bond lengths in 4 are significantly (about 0.029 Å) longer than in 5. It is suggested that variation of the π bond order in the C—O bonds is responsible for the shifts in the electronic spectra observed for the various chelates of 1,3-diketones and related compounds.
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    2-Azaallenium salts from the reaction of 1-oxa-3-azabutatrienium salts with cyanamides and carbodiimides (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1887-1902 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Darstellung von 2-Azaallenium-Salzen durch Reaktionen von 1-Oxa-3-azabutatrienium-Salzen mit Cyanamiden und CarbodiimidenDie 1-Oxa-3-azabutatrienium-Salze 2 reagieren mit disubstituierten Cyanamiden unter [2 + 2 + 2]-Cycloaddition zu den 2-(Alkylidenamino)-4,6-diamino-1,3,5-oxadiazinium-Salzen 7a - o, die man als oxysubstituierte 2-Azaallenium-Salze betrachten kann. Durch Anlagerung von Methanol entstehen die Oxadiazinium-Salze 8a, d, p. Aus 2n und Dimethylcyanamid erhält man das 2-Azaallenium-Salze 11, dessen Bildung eine [1,5]-isocyanatotrope Umlagerung einschließt. Die Butatrienium-Salze 2 reagieren meist mit zwei Äquivalenten Carbodiimid vom Typ R1 — N = C = N — CHR22 zu den 2-Azaallenium-Salzen 17a - k, die durch eine [1,5]-Hydridverschiebung entstehen. Sterisch anspruchsvoll substituierte Butatrienium-Salze 2 lagern drei Moleküle Diisopropylcarbodiimid and und ergeben die 1,3,5-Triazinium-Salze 20n, o. Es werden Röntgenstruktur-analysen der Verbindungen 7a und 17a angegeben.
    Notes: 1-Oxa-3-azabutatrienium salts 2 react with disubstituted cyanamides under [2 + 2 + 2] cycloaddition affording the 2-(alkylideneamino)-4,6-diamino-1,3,5-oxadiazinium salts 7a - o, which can be regarded as oxy-substituted 2-azaallenium salts. Addition of methanol leads to the oxadiazinium salts 8a, d, p. From 2n and dimethylcyanamide the 2-azaallenium salt 11 was obtained, which must be formed by an [1,5] isocyanatotropic rearrangement. Most butatrienium salts 2 react with two equivalents of carbodiimides R1 — N = C = N — CHR22 to form the 2-azaallenium salts 17a - k. The reaction mechanism includes an [1,5] hydride shift. Bulky substituted butatrienium salts 2 add three molecules of diisopropylcarbodiimide to give the 1,3,5-triazinium salts 20n, o. X-Ray structural analyses for 7a and 17a are reported.
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    Iminokohlenstoff-Dianionen der C4-Reihe mit Cyaniminofunktionen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1903-1916 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Iminocarbon Dianions of the C4-Series with Cyanoimino GroupsSuitable activated squaric acid derivatives react with the anion of cyanamide to yield novel iminocarbon dianions of the C4-series 8 - 11, in which the oxygens of the squarate dianion are successively replaced by one, two, three, or four cyanoimino groups. Besides the synthesis of mixed substituted iminocaron monoanions such as 12, 13, 25, and 26 is described. Spectroscopic data are discussed, 13C NMR data are compared with those of other pseudooxocarbons of the C3- and C4-series. The structure of the first isolable C4-iminocarbon 11′ is proved by X-ray diffraction, which confirmed 11′ to be a delocalized bond system just like the squarate dianion or the other pseudooxocarbons of the C4-series.
    Notes: Geeignet aktivierte Quadratsäurederivate lassen sich mit dem Anion des Cyanamids zu neuen Iminokohlenstoff-Dianionen der C4-Reihe 8 - 11 umsetzen, in denen die Sauerstoffunktionen des Quadratats sukzessive durch ein, zwei, drei oder vier Cyaniminogruppen ersetzt sind. Daneben wird die Darstellung gemischt substituierter Iminokohlenstoff-Monoanionen wie 12, 13, 25 und 26 beschrieben. Spektroskopische Daten werden diskutiert, 13C-NMR-Daten mit denen anderer Pseudooxokohlenstoffe der C3- und C4-Serie verglichen. Die Konstitution des ersten isolierbaren C4-Iminokohlenstoffs 11′ wird durch eine Röntgenstrukturanalyse belegt, die bestätigt, daß 11′ analog dem Quadratat und den anderen Pseudooxokohlenstoffen der C4-Reihe ein delokalisiertes Bindungssystem besitzt.
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    Anisotropieeffekte konjugierter cyclischer Systeme, VI. Struktur und magnetische Anisotropie mesitylsubstituierter Ferrocene (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1968-1982 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Anisotropy Effects of Conjugated Cyclic Systems, VI. Structure and Magnetic Anisotropy of Mesityl-substituted FerrocenesTwo isomeric ferrocene derivatives have been obtained from 2-(2-ethyl-4,6-dimethylphenyl)-1,3-dimethylcyclopentadiene (22a). The exo,exo- (9) as well as the endo,endo-configuration (10) of these were determined by X-ray structure analysis. The assignment of the 1H NMR signals of the methyl groups in the spectrum of 1,1′,3,3′-tetramethyl-2,2′-dimesitylferrocene (7) is derived from the spectra of 9 and 10. Signals of methyl groups in exo-position of the mesitylferrocene are shifted by -0.74 ppm to higher magnetic field. Signals of methyl groups in endo-position directed towards the iron atom are shifted downfield by +0.71 ppm. Therefore, ferrocene develops a diamagnetic anisotropy which is similar to that of benzene.
    Notes: Aus 2-(2-Ethyl-4,6-dimethylphenyl)-1,3-dimethylcyclopentadien (22a) werden zwei isomere Ferrocenderivate erhalten. Durch Röntgenstrukturanalysen wird deren exo,exo-(9) bzw. endo,endo-Konfiguration (10) bestimmt. Anhand der 1H-NMR-Spektren dieser Ferrocene ist die Zuordnung der Methylgruppensignale im 1H-NMR-Spektrum des 1,1′,3,3′-Tetramethyl-2,2′-dimesitylferrocens (7) bewiesen. Signale von Methylgruppen in exo-Stellung des Mesitylferrocens werden um -0.74 ppm nach hohem Magnetfeld und solche von zum Eisenatom gerichteten in endo-Stellung um +0.71 ppm nach tiefem Feld verschoben. Daraus leitet sich für Ferrocen eine dem Benzol ähnliche diamagnetische Anisotropieverteilung ab.
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    Synthese und Struktur von Lithiumkomplexen mit pentahapto-gebundenen Tris(trimethylsilyl)cyclopentadienyl-Liganden (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1959-1967 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structure of Lithium Complexes with pentahapto-Bonded Tris(trimethylsilyl)cyclo-pentadienyl LigandsReaction of tris(trimethylsilyl)cyclopentadienyllithium (2) with the nitrogen bases quinuclidine, tetramethylethylenediamine, and pentamethyldiethylenetriamine leads to the isolation of the crystalline, air-sensitive 1:1-adducts 3, 4, and 5, resp., which are monomeric in the gas phase, in solution, and in the solid state. X-Ray structure determinations show that in 3-5 the cyclopentadienyl ring is pentahapto-bonded to the lithium atom. The bonding in these π-complexes is discussed; the complex 3 fulfills the criteria for a nido-cluster.
    Notes: Umsetzung von Tris(trimethylsilyl)cyclopentadienyllithium (2) mit den Stickstoffbasen Chinuclidin, Tetramethylethylendiamin und Pentamethyldiethylentriamin führt zur Isolierung der kristallinen, luftempfindlichen 1:1-Addukte 3, 4 und 5, die in der Gasphase, in Lösung und im festen Zustand monomer vorliegen. Kristallstrukturuntersuchungen zeigen, daß in 3-5 der Cyclopentadienylring pentahapto an das Lithiumatom gebunden ist. Die Bindungsverhältnisse in diesen π-Komplexen werden diskutiert; der Komplex 3 erfüllt die Kriterien für einen nido-Cluster.
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    Selektive Reduktion von Cyclohexadienonen mit Fe2(CO)9 und Wasser (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1983-1995 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Selective Reduction of Cyclohexadienones with Fe2(CO)9 and waterSelective monohydrogenation of cross conjugated 2,5-cyclohexadien-1-ones 1 with Fe2(CO)9 and water forming under unusually mild conditions the cyclohexadienol complexes 2 is applied to various related compounds. The regioselectivity of this reaction is tested with differently substituted derivatives. A mechanism explaining the observed regioselectivities and the pH dependence of the stereochemistry is discussed.
    Notes: Die unter ungewöhnlich milden Bedingungen verlaufende selektive Monohydrierung gekreuzt konjugierter 2,5-Cyclohexadien-1-one 1 mit Fe2(CO)9 und Wasser zu den Cyclohexadienol-Komplexen 2 wird auf verschiedene verwandte Verbindungen übertragen. Die Regioselektivität der Reaktion wird an unterschiedlich substituierten Derivaten geprüft. Es wird ein Mechanismus diskutiert, der die beobachteten Regioselektivitäten und die pH-Abhängigkeit der Stereochemie erklärt.
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  • 85
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    Synthese mittlerer und großer Ringe, X. (+)- und (-)-[6]Paracyclophan-8-carbonsäure aus (+)- und (-)-3,6-Hexanooxepin-4-carbonsäure (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1996-2010 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of Medium and Large Rings, X. (+)- and (-)-[6]Paracyclophane-8-carboxylic Acid from (+)- and (-)-3,6-Hexanooxepin-4-carboxylic AcidThe racemic 3,6-hexanooxepin-4-carboxylic acid ((±)-2d), available in five steps from cyclooctyne and 3-(acetoxymethyl)furan, can be resolved into the enantiomers (+)- and (-)-2d using (+)(R)-1-(1-naphthyl)ethylamine. A stereospecific synthesis of (+)- and (-)-[6]paracyclophane-8-carboxylic acid ((+)- and (-)-4b) is possible from (+)- and (-)-2d as starting materials. Key steps of this synthesis are the transannular addition of bromine to give (-)- and (+)-3a and a subsequent McMurry reaction. The problems involved in the interpretation of the CD-spectra of the oxepin ester (+)-2e and of (+)-4b are discussed in detail.
    Notes: Die aus Cyclooctin und 3-(Acetoxymethyl)furan in fünf Stufen erhältliche racemische 3,6-Hexanooxepin-4-carbonsäure ((±)-2d) kann mit (+)(R)-1-(1-Naphthyl)ethylamin in die Enantiomeren (+)- und (-)-2d gespalten werden. Ausgehend von (+)- und (-)-2d ist eine stereospezifische Synthese von (+)- und (-)-[6]Paracyclophan-8-carbonsäure ((+)- und (-)-4b) möglich. Schlüsselschritte sind dabei die transannulare Bromaddition zu (-)- und (+)-3a und eine anschließende McMurry-Reaktion. Die Probleme der Interpretation der CD-Spektren des Oxepinesters (+)-2e und der Phancarbonsäure (+)-4b werden eingehend diskutiert.
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19851180523
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    Beiträge zur Chemie des Bors, 152. 1,3,2,4-Diazaphosphaboretidine und 1,3,2,4-Diazasilaboretidine durch intra- und intermolekulare Cyclokondensation (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2030-2043 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, 152. 1,3,2,4-Diazaphosphaboretidines and 1,3,2,4-Diazasilaboretidines Prepared via Intra- and Intermolecular Cyclocondensation1,3,2,4-Diazaphospha(sila)boretidines 5 and 9 are accessible via thermal decomposition of compounds of type E(NR′—BR2)2 (8) or from organoboron dihalides or boron trihalides and E(NR′Li)2 [E = Si(CH3)2, CH3(O)P, R(S)P, CH3P]. The formation of 1,3-di-tert-butyl-4-methyl-(or ethyl)-1,3,2,4-diazaphospha(sila)boretidines from the precursor E(NR′—BR2)2 proceeds by an intramolecular cyclocondensation. NMR data reveal less shielded B and P atoms in the new heterocycles as compared with noncyclic compounds; this is attributed to a strained ring system. A tetracoordinated as well as a tricoordinated boron atom is observed in CH3(O)P(NR′BR2)2 compounds resulting from intramolecular BO coordination.
    Notes: 1,3,2,4-Diazaphospha(sila)boretidine 5 und 9 sind über die thermische Zersetzung von Verbindungen des Typs E(NR′-BR2)2 (8) oder durch Umsetzung von Organylbordihalogeniden bzw. Bortrihalogeniden mit N-Lithio-Verbindungen E(NR′Li)2 [E = Si(CH3)2, CH3(O)P, R(S)P, CH3P] zugänglich. Es wird gezeigt, daß die 1,3-Di-tert-butyl-4-methyl-bzw. -4-ethyl-1,3,2,4-diazaphospha(sila)boretidine aus der Vorstufe E(NR′-BR2)2 durch eine intramolekulare Cyclokondensation entstehen. Nach NMR-Daten sind die Bor- und Phosphor-Kerne in den Vierring-Heterocyclen als Folge der Ringspannung schlechter abgeschirmt als in nichtcyclischen Derivaten. Vierfach koordiniertes Bor liegt neben dreifach koordiniertem in den Verbindungen CH3(O)P-(NR′BR2)2 vor. Dies geht auf intramolekulare BO-Koordination zurück.
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    URL: http://dx.doi.org/10.1002/cber.19851180526
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    Synthese von 4-Oxo-4H-benzothiazolo[3,2-a]pyrimidin-1-ium-2-olaten und ihre Cycloadditionen an elektronenarme und elektronenreiche Alkine sowie an o-Chloranil (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 2079-2094 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 4-Oxo-4H-benzothiazolo[3,2-a]pyrimidin-1-ium-2-olates and their Cycloaddition Reactions to Electron-poor and Electron-rich Alkynes as well as to o-ChloranilThe synthesis and physical properties of the title compounds 3a - d, prepared from 1 and bis(2,4,6-trichlorophenyl) malonates 2a - d, are described. As cyclic 1,4-dipoles, the betaines 3 combine with dimethyl acetylenedicarboxylate, dibenzoylethyne or bis(diethylamino)ethyne with formation of primary adducts of type 4, which release methyl isocyanate to give pyrido[2,1-b]-benzothiazole derivatives 5a - g, whereas the reaction of 3a with bis(diethylamino)ethyne yields the betaine 7. With unsymmetrically substituted alkynes like methyl propiolate or 1-(diethyl-amino)propyne, 3 reacts with regiospecific formation of 8a - f. On the other hand, the reaction of 3a with o-chloranil proceeds with regiospecific formation of the 1,4-benzodioxin derivative 11. In the case of 8, the observed regiospecificities are in agreement with the results of MNDO calculations and MO-perturbation theory.
    Notes: Die Synthese und physikalischen Eigenschaften der Titelverbindungen 3a - d aus 1 und Malonsäure-bis(2,4,6-trichlorphenylestern) 2a - d werden beschrieben. Als cyclische 1,4-Dipole vereinigen sich die Betaine 3 mit Acetylendicarbonsäure-dimethylester, Dibenzoylethin oder Bis(diethyl-amino)ethin zu Primäraddukten vom Typ 4, die unter Methylisocyanat-Abspaltung Pyrido-[2,1-b]benzothiazol-Derivate 5a - g liefern, während 3a mit Bis(diethylamino)ethin das Betain 7 ergibt. Mit unsymmetrisch substituierten Alkinen, wie Propiolsäure-methylester oder 1-(Diethyl-amino)propin, reagiert 3 regiospezifisch zu 8a - f. Andererseits führt die Umsetzung von 3a mit o-Chloranil regiospezifisch zu dem 1,4-Benzodioxin-Derivat 11. Die bei 8 beobachteten Regiospezifitäten sind mit den Ergebnissen aus MNDO-Rechnungen und der MO-Störungstheorie in Einklang.
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    Thermolabile Hydrocarbons, XXVII. 2,3-Di-1-adamantyl-2,3-dimethylbutane; Long Bonds and Low Thermal Stability (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 4665-4673 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Thermolabile Kohlenwasserstoffe, XXVII. 2,3-Di-1-adamantyl-2,3-dimethylbutan; lange Bindungen und geringe thermische StabilitätDie Titelverbindung 2 wurde durch Wurtz-Synthese dargestellt und eine Kristallstrukturanalyse durchgeführt. Die Strukturdaten des sehr stark deformierten Molekülgerüstes - drei benachbarte CqCq-Bindungen sind länger als 164 pm, CqCqCq-Bindungswinkel sind bis 118° aufgeweitet - werden durch Rechnungen mit dem MM 2-Kraftfeld sehr gut wiedergegeben. Nach den Kraftfeldrechnungen ist 2 der am stärksten gespannte, nach kinetischen Messungen der thermisch labilste Vertreter der bereits früher bearbeiteten CqCq-Alkane.
    Notes: The title compound 2 was prepared by a Wurtz procedure. Its highly deformed structure was determined by X-ray analysis and matched with high precision by MM 2 force field calculations. The three neighbouring CqCq bonds are longer than 164 pm and the CqCqCq bond angles are 118°. According to MM 2 calculations and a kinetic investigation 2 is the most strained and least stable member of the CqCq alkane series investigated previously2).
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    Hauptgruppenelement-Übergangsmetall-Mehrfachbindungen, IV. Katalytische Assistenz von [Cp(CO)3Mo]2 bei der Aggregation von Metallo-arsanen über Arsen-Metall-Doppelbindungskomplexe (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 378-382 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Main Group Element Transition Metal Multiple Bonds, IV. Catalytic Assistance by [Cp(CO)3Mo]2 in the Aggregation of Metallo-arsanes via Arsenic Metal Double Bond Complexes2)The metallo-arsanes Cp(CO)3M—AsMe2 (1a, b) (M = Mo, W) are converted to the double arsenido-bridged dinuclear complexes [(μ-AsMe2)Mo(CO)2Cp]2 (3a, b) in the presence of [Cp(CO)3Mo]2. Due to the unusual mild conditions of aggregation the intermediate formation of the double bonded species Cp(CO)2M=AsMe2 (2a, b) is postulated. The crystal structure of 3a is reported, which shows mutual trans arrangement of the cyclopentadienyl and CO ligands.
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    URL: http://dx.doi.org/10.1002/cber.19861190133
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    Aliphatische Flüssigkristalle, 7. Einige mesogene Tercyclohexylderivate (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 387-400 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Aliphatic Liquid Crystals, 7. Some Mesogenic Tercyclohexyl DerivativesStarting from bicyclohexyl-4-one 1 the tercyclohexyl-3-one 6 is synthesized via the acetyl derivatives 3a,b. Methoxycarbonylation of 6 gives the keto ester 12 which on the one hand is tranformed to the esters 15a,b and 17 - 20 and the nitriles 21a,b, on the other hand to the methylated keto esters 23a,b and 24a,b. From 23a the ester 26 with an axial 1-methyl group is obtained. Nearly all the products are mesogenic.
    Notes: Aus dem Bicyclohexyl-4-on 1 wird über die Acetylderivate 3a,b das Tercyclohexyl-3-on 6 aufgebaut, daraus durch Methoxycarbonylierung der Ketoester 12, der einerseits zu den Estern 15a,b und 17 - 20 und den Nitrilen 21a,b, andererseits zu den methylierten Ketoestern 23a,b und 24a,b umgesetzt wird. Aus 23a erhält man den Ester 26 mit axialer 1-Methylgruppe. Fast alle Produkte sind mesogen.
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    Vitamin-Synthese mit Carben-Komplexen, VI. Stereospezifische Darstellung von Pentacarbonyl[(Z)-dimethoxy-vinyl]carben-Komplexen des Chroms und Wolframs (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1126-1132 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Vitamin Syntheses via Carbene Complexes, VI. Stereospecific Synthesis of Pentacarbonyl[(Z)-dimethoxyvinyl]carbene Complexes of Chromium and TungstenThe addition of (E,Z)-1-lithio-1,2-dimethoxyethene (1) to hexacarbonylchromium and -tungsten followed by protonation or alkylation, respectively, provides a stereospecific route to pentacabonyl[(Z)-1,2-dimethoxyvinyl]carbene complexes 2-5. Established by X-ray analysis, the carbene ligand of the methoxycarbene chromium complex 3 is nearly coplanar.
    Notes: Die Addition von (E,Z)-1-Lithio-1,2-dimethoxyethen (1) an Hexacarbonylchrom und -wolfram liefert nach Protonierung bzw. Alkylierung stereospezifisch die Pentacarbonyl[(Z)-1,2-dimeth-oxyvinyl]carben-Komplexe 2-5. Nach der Röntgenstrukturanalyse des (Methoxycarben)chrom-Komplexes 3 ist der gesamte Carbenligand annähernd koplanar.
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    Zwei neue Metallcarbonyle: Darstellung und Struktur von RuCo2(CO)11 und Ru2Co2(CO)13 (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1133-1142 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Two New Metal Carbonyls: Preparation and Structure of RuCo2(CO)11 and Ru2Co2(CO)13RuCo2(CO)11 (1) results from the stoichiometric and heterogeneous reaction between KCo(CO)4 and [Ru(CO)3Cl2]2 in water. Its decomposition in hexane at 65°C yields Ru2Co2(CO)13 (2). The crystallographically determined molecular structures of both compounds show that their metal atom cores are located inside approximately regular ligand polyhedra.
    Notes: RuCo2(CO)11 (1) entsteht durch stöchiometrische heterogene Umsetzung von KCo(CO)4 und [Ru(CO)3Cl2]2 in Wasser. Seine Zersetzung bei 65°C in Hexan liefert Ru2Co2(CO)13 (2). Die kristallographisch bestimmten Molekülstrukturen beider Verbindungen lassen erkennen, daß ihre Metallatom-Kerne sich in annähernd regelmäßigen Ligandenpolyedern befinden.
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    Synthese und Struktur eines hochsubstituierten Tetracyclo[3.3.0.02,8.04,6]octans (Nortriasteran) (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 1176-1182 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structure of a Highly Substituted Tetracyclo[3.3.0.02,8.04,6]octane (Nortriasterane)The 4,8-dibromobicyclo[3.3.0]octa-2,6-diene-2,6-dicarbonitrile 2 reacts with sodium methoxide in methanol quantitatively and with complete stereoselectivity to afford the nortriasteranedicarbonitrile 5. This dinitrile crystallizes triclinically in the space group P1 with two enantiomorphous molecules per cell. Some geometric parameters involving the cyclopropane rings and the mechanism of formation of 5 are discussed.
    Notes: Das 4,8-Dibrombicyclo[3.3.0]octa-2,6-dien-2,6-dicarbonitril 2 reagiert mit Natriummethanolat in Methanol quantitativ und vollständig stereoselektiv zum Nortriasterandicarbonitril 5. Dieses kristallisiert triklin in der Raumgruppe P1 mit zwei enantiomorphen Molekülen in der Elementarzelle. Einige geometrische Parameter der Cyclopropanringe und der Bildungsmechanismus von 5 werden diskutiert.
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    URL: http://dx.doi.org/10.1002/cber.19851180333
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    Beiträge zur Chemie des Bors, 169. Sterisch anspruchsvolle N-Lithioaminoborane: Reagentien zur Synthese symmetrisch und unsymmetrisch substituierter Diborylamine (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1361-1373 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Boron, 169. Sterically Demanding N-Lithioaminoboranes: Reagents for the Synthesis of Symmetrically and Unsymmetrically Substituted DiborylaminesN-Metalation of R2BNH2 or R2BNMeH yields lithium amides R2BNR′Li with sterically demanding R groups (R = tBu, iPr). These compounds are synthons for symmetrically or unsymmetrically substituted diborylamines as well as for B-functional diborylamines. NMR data reveal the conformation of these diborylamines. Compounds of the type tBu2B—NMe—BR2 contain tBu2B groups whose BC2 plane stands nearly orthogonal to the B2NC skeleton. In contrast, the BRX group in diborylamines of the type tBu2B—NH—BRX is strongly twisted with respect to the B2NH plane.
    Notes: Durch N-Metallierung erhältliche Lithiumamide R2BNR′Li mit sperrigen Substituenten R = tBu, iPr eignen sich sowohl zur Darstellung symmetrisch und unsymmetrisch substituierter Diborylamine als auch zur Gewinnung B-funktioneller Diborylamine. Kernresonanzspektroskopische Untersuchungen zeigen, daß Diborylamine tBu2B—NMe—BR2 eine tBu2B-Gruppe enthalten, deren BC2-Ebene weitgehend orthogonal zur B2NC-Gerüstebene steht. In Diborylaminen tBu2B—NH—BRX ist hingegen die BRX-Gruppe gegen die B2NH-Ebene verdrillt.
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    URL: http://dx.doi.org/10.1002/cber.19861190423
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    Mehrfachbindungen zwischen Hauptgruppenelementen und Übergangsmetallen, XXV. Aufbau und Reaktivität von Se1- und Se2-Brücken in Organochrom-Komplexen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1437-1440 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Multiple Bonds Between Main Group Elements and Transition Metals, XXV. Synthesis and Reactivity of Se1- and Se2-Bridges in Organochromium CompoundsReaction of the ionic complex K[(η5-C5Me5)Cr(CO)3] (1) with selenium(I) with selenium(I) chloride, Se2Cl2, yields the diselenium compounds 2 of composition (η5-C5Me5)Cr(CO)5Se2 which is converted to the Se1 derivative (μ-Se)[η5-C5Me5)Cr2(CO)2]2 (3) with triphenylphosphane. 3 exhibits a linear, multiple bonded CrSeCr core structure. Reaction of 2 with diazomethane gives the novel mononuclear, paramagnetic selenoformaldehyde complex (η5-C5Me5)-Cr(CO)2(SeCH2) (4).
    Type of Medium: Electronic Resource
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    Masthead (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986) 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190501
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  • 97
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    N-tert-Butylpivalohydroxamsäure: s-trans-Konformation und H-Brückenbindungen im Kristall (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1441-1444 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N-tert-Butylpivalohydroxamic Acid: s-trans-Conformation and H-Bonding in the CrystalIt is shown by an X-ray crystal structure analysis that, in the crystal, teh title compound has the s-trans-conformation and the molecules are linked by strong intermolecular H-bonds to linear chains.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19861190431
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    Synthesen von 2,6,7-Triazabicyclo[2.2.2]oct-2-en-5,8-dionen und 4(3H)-Pyrimidinonen durch 1,4-Dipolare Cycloadditionen von Pyrimidinium-4-olaten an Nitrile (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1445-1454 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of 2,6,7-Triazabicyclo[2.2.2]oct-2-ene-5,8-diones and 4(3H)-Pyrimidinones via 1,4-Dipolar Cycloaddition Reactions of Pyrimidinium-4-olates to NitrilesThe 3,6-dihydro-6-oxo-1-pyrimidinium-4-olate 1a, which carry no substituent in the 2 position, undergoes 1,4-dipolar cycloaddition reactions with ethyl cyanoformate (2a) and benzoyl cyanide (2b) to produce novel bicyclic primary adducts 3a, b, respectively, which at higher temperature fragment into 4(3H)-pyrimidinones 4a, b with elimination of phenyl isocyanate. However, pyrimidinium-4-olates 1b - h or 5, which are substituted in the 2 position, react directly with nitriles 2a - c to form high yields of 4(3H)-pyrimidinone derivatives of type 4 or 7, respectively. Furthermore, the reactions of 1a with isocyanic acid as well as with cyan amide are described.
    Notes: Das in 2-Position unsubstituierte 3,6-Dihydro-6-oxo-1-pyrimidinium-4-olat 1a geht mit Cyanameisensäure-ethylester (2a) und Benzoylcyanid (2b) 1,4-Dipolare Cycloadditionen zu neuen bicyclischen Primäraddukten 3a bzw. b ein, die bei höherer Temperatur unter Phenylisocyanat-Abgabe in 4(3H)-Pyrimidinone 4a, b fragmentieren. Dagegen reagieren die in 2-Stellung substituierten Pyrimidinium-4-olate 1b - h oder 5 mit Nitrilen 2a - c in hohen Ausbeuten direkt zu den 4(3H)-Pyrimidinon-Derivaten vom Typ 4 bzw. 7. Weiterhin werden die Reaktionen von 1a mit Isocyansäure sowie mit Cyanamid beschrieben.
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    URL: http://dx.doi.org/10.1002/cber.19861190502
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    Über sterisch gehinderte freie Radikale, XV. Das erste unsymmetrische Dimere aus zwei stabilen Radikalen: 3-(tert-Butylphenylmethylen)-6-(triphenylmethyl)-1,4-cyclohexadien aus tert-Butyldiphenylmethyl und Triphenylmethyl (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2006-2012 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sterically Hindered Free Radicals, XV. The First Unsymmetrical Dimer from Two Different Stable Radicals: 3-(tert-Butylphenylmethylene)-6-(triphenylmethyl)-1,4-cyclohexadiene from tert-Butyldiphenylmethyl and TriphenylmethylThe quinonoid title compound 6 is formed in an equilibrium to 95% and can be isolated, when the two title radicals 1 and 3 are generated in solution. The reason for this is the sterically less strained position of the bulky tBu group at the sp2-C atom of the methylene group. The structure of 6 is proved by 1,5-H migration giving 8 and autoxidation of the latter at -10°C giving tBuOH and 4-tritylbenzophenone (12). The synthesis of several analogous compounds are described.
    Notes: Die chinoide Titelverbindung 6 entsteht im Gleichgewicht zu 〉95% und kann isoliert werden, wenn die beiden Titelradikale 1 und 3 in Lösung erzeugt werden. Ursache hierfür ist die räumlich günstigere Unterbringung der sperrigen tBu-Gruppe am sp2-C-Atom der Methylengruppe. Die Struktur von 6 wird durch 1,5-H-Verschiebung zu 8 sowie dessen Autoxidation bei -10°C zu tBuOH und 4-Tritylbenzophenon (12) bewiesen. Synthesen analoger Verbindungen werden beschrieben.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190621
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    Der Einfluß von Phenylgruppen auf die Homokonjugation im Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anion. Eine 13C-NMR-Studie (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2025-2049 
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    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Effect of Phenyl Groups on the Homoconjugation in the Bicyclo[3.2.1]octa-3,6-dien-2-yl Anion. A 13C NMR StudyThe effects of deuterium atoms in the positions 2 and 4 of exo-6-bromo- (11) and endo-6-methoxytricyclo[3.2.1.02,7]oct-3-ene (12) as well as exo-4-methoxybicyclo[3.2.1]octa-2,6-diene (13) on their 13C chemical shifts are in line with the previous interpretation of the effects in correspondingly deuterated bicyclo[3.2.1]octa-3,6-dien-2-yl anions 1, and thus provide evidence for the homoconjugative interaction in 1. 3-Phenylbicyclo[3.2.1]octa-2,6-diene (16) and endo- (19a) as well as exo-4-phenylbicyclo[3.2.1]octa-2,6-diene (19b) have been prepared from bicyclo[3.2.1]oct-6-en-3-one (14) and bicyclo[3.1.0]hex-2-ene-endo-6-carbaldehyde (17), respectively. 2,4-Diphenylbicyclo[3.2.1]octa-2,6-diene (6) and 19a, b were deprotonated by methyllithium and n-butyllithium, respectively, whereas the proton abstraction from tricyclo[6.3.1.02,7]dodeca-2,4,6,9-triene (4) and from 16 required potassium tert-butoxide/n-butyllithium. As products the corresponding bicyclo[3.2.1]octa-3,6-dien-2-yl anion derivatives have been identified. By means of potassium tert-butoxide/n-butyllithium 19a, b were converted into 21K, i.e. the anion with K+ as counterion. The NMR spectra of 21Li turned out to depend upon the temperature in the range between +45 and -30°C in contrast to those of 21K. The 13C NMR spectra of the anions and of the corresponding hydrocarbons are discussed in detail in relation to the spectra of the unsubstituted species 1 and 2. In particular, the wide variations of the chemical shifts of C-6,7 depending upon the substituents of the allylic moiety of the bicyclo[3.2.1]octa-3,6-dien-2-yl anion system give strong support for the bishomoaromatic nature of these anions.
    Notes: Die Effekte von Deuteriumatomen in den Positionen 1 und 4 von exo-6-Brom- (11) und endo-6-Methoxytricyclo[3.2.1.02,7]oct-3-en (12) sowie exo-4-Methoxybicyclo[3.2.1]octa-2,6-dien (13) auf deren 13C-chemische Verschiebungen stützen die frühere Interpretation der Effekte bei entsprechend deuterierten Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionen 1 und belegen so die homokonjugative Wechselwirkung in 1.  -  Ausgehend von Bicyclo[3.2.1]oct-6-en-3-on (14) und Bicyclo[3.1.0]hex-2-en-endo-6-carbaldehyd (17) stellte man 3-Phenyl- (16) bzw. endo-4-Phenyl-(19a) und exo-4-Phenylbicyclo[3.2.1]octa-2,6-dien (19b) dar. 2,4-Diphenylbicyclo[3.2.1]octa-2,6-dien (6) und 19a, b wurden mit Methyllithium bzw. n-Butyllithium, Tricyclo[6.3.1.02,7]dodeca-2,4,6,9-tetraen (4) sowie 16 mit Kalium-tert-butoxid/n-Butyllithium deprotoniert, wobei die entsprechenden Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionderivate 7, 21Li, 5 und 22 entstanden. Aus 19a, b wurde mit Kalium-tert-butoxid/n-Butyllithium auch 21K, d. h. das zugehörige Anion mit K+ als Gegenion erhalten. Die NMR-Spektren von 21Li erwiesen sich im Gegensatz zu jenen von 21K im Bereich von +45 bis -30°C als temperaturabhängig. Die 13C-NMR-Spektren der Anionen und der zugehörigen Kohlenwasserstoffe werden im Vergleich mit den Spektren der unsubstituierten Verbindungen 1 und 2 ausführlich diskutiert. Insbesondere die starken Variationen der chemischen Verschiebungen von C-6,7 in Abhängigkeit von den Substitutenten am Allylteil des Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anionsystems bieten ein starkes Argument für die bishomoaromatische Natur dieser Anionen.
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    URL: http://dx.doi.org/10.1002/cber.19861190623
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