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1.
2.
The reactions of organolithium reagents and Grignard reagents with optically active alkoxygermanes R3GeOR′ have been studied [R3GeOR′ = ()-i-PrPhNpGeOCH3, ()-i-PrPhNPGeOMen and ()-MePhNpGeOMen]. Saturated reagents (e.g. butyllithium) give retention of configuration at germanium whilst unsaturated reagents (e.g. allyl- or benzyllithium) lead to inversion. 相似文献
3.
Geneviéve Cerveau Ernesto Colomer Robert J.P. Corriu J.Colin Young 《Journal of organometallic chemistry》1981,205(1):31-45
We report the chemical behavior of cobalt-stabilized carbenes, R3M(CO)3CoC(OEt)R′, and their parent anions, R3M(CO)3CoC(O?)R′, where M = Si or Ge. The anions where M = Si, R′ = Ph decompose thermally into the corresponding benzoylsilanes; when the silicon atom is chiral (R3 = MePh-1-Np) optically active R3SiCOPh is obtained with complete retention of configuration. 相似文献
4.
The reaction of various organometallics with cyclic and acyclic dialkoxysilanes has been studied.In the case of the acyclic compounds, phenyl-α-naphthylmethoxyborneoxy- and phenyl-α-naphthylmethoxycyclohexyloxy-silane, our results confirm those previously observed with phenyl-α-naphthylmethoxymethoxysilane. The reactions are selective. In ether, aromatic and saturated organomagnesium compounds substitute only the methoxy group with retention, but allylic and benzylic organomagnesium substitute the bulky alkoxy group with inversion.In THF and DME, irrespective of the type of organomagnesium compound, the methoxy group alone is substituted with retention of configuration.With the cyclic compounds, 2-methoxy-2-silaindane, both methoxy and menthoxy groups are substituted and our results confirm the tendency of cyclic derivatives to be substituted with retention of configuration. 相似文献
5.
Moni Chauhan Claude Chuit Robert J. P. Corriu Catherine Rey Jean-Paul Declercq Antoine Dubourg 《Journal of organometallic chemistry》1996,510(1-2):173-179
The X-ray structure analysis of bis(8-dimethylamino-l-naphthyl)phenylphosphane (3) and of the corresponding sulphide 4 has revealed hexacoordination at phosphorus in both cases, the N … P separations being less than the sum of the van der Waal radii. Furthermore, in both cases the overall geometry corresponds to a distorted bicapped tetrahedron. The optimum geometry calculated for 4 via the
program developed by Autodesk (MM + method) suggests that the structure of the molecule is a function not only of steric requirements but also of electronic effects. 相似文献
6.
Hydrosilylation of saturated and α,β-unsaturated carbonyl compounds by heterogeneous catalysis without solvent and in the presence of salts (HCO2K, o-Ph(CO2K)2, FK, FCs) was carried out with good yields. FCs is a very efficient salt for hydrosilylation of aldehydes and ketones: for instance α-NpSiH3 reacts quantitatively at room temperature with PhCOPh giving α-NpSi(OCHPh2)3. With α,β-unsaturated ketones FCs leads to 1,2-addition. It allows the isomerization of allysilyl ethers in silyl enol ethers, providing that the transferring hydrogen is benzylic. 相似文献
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8.
R. J. P. Corriu G. F. Lanneau D. Leclercq 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):197-200
Abstract Opposite to the SN2(P) reactions taking place with inversion, which are highly dependent upon the nature of the nucleophile, exocyclic substitutions of five-membered ring chlorophosphates with retention show a marked kinetic levelling effect, emphasing silicon-type argumentations. 相似文献
9.
J. Kowalski J. Chojnowski R. J. P. Corriu R. Royo 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Kinetics of base catalysed solvolytic cleavage of phenoxy group from compounds of general structure X (CH2)nSiMe2OPh, where n=1,2,3 and X=Me,Ph2P, Ph2P (p), Ph2P(s) has been investigated. The main purpose was to study the effect of phosphorus groups on the reactivity in substitution reaction at silicon. We wanted to answer the question whether there is any direct interaction of the phosphorus groups with silicon moiety, modifying this reactivity. Complementary NMR studies have also been performed for this purpose. 相似文献
10.