Gas phase reaction of dichlorogermylene with the chlorine-substituted ethylenes

Gas phase reaction of dichlorogermylenes formed in the systems GeCl₄-Si₂Cl₆ or Ge-GeCl₄ with 1,2-dichloroethylene and trichloroethylene was studied. It is shown that:GeCl₂ inserts into the C-Cl bond of 1,2-dichloroethylene and forms the derivatives with one or two trichlorogermyl groups. A specific feature of the reaction of:GeCl₂ with trichloroethylene was found. In this reaction the formation of only monosubstituted compounds like 1,1-dichloro-2-trichlorogermylethylene and 1,2-dichloro-1-trichlorogermylethylene takes place. The rule established is valid in general also for the reaction of trichloroethylene with dichlorosilylene, another analog of carbene. Reactions taking place in the course of synthesis of organochlorogermanes are considered.     

Effect of Substituents on the Silicon Atom on Etherification of Organochlorosilanes with Ethanol

The kinetics of etherification of organochlorosilanes with various substituents on the silicon atom with ethanol were studied. The etherification rate is mostly controlled by the inductive constants of the substituents and increases as the electron-acceptor power of the substituents increases. The ^* value in the Taft equation for etherification of organochlorosilanes with ethanol was determined.     

Advances in the gas-phase synthesis of organochloro derivatives of silicon, germanium, and tinvia dichlorosilylene

The results of studies carried out in the past five years on the gas-phase synthesis of organochlorosilanes, pentachlorodisiloxanes, organochlorogermanes, and organochlorostannanes at 400–550 °C in the presence of hexachlorodisilane or 1,1-dichloro-1-silacyclopent-3-ene as sources of dichlorosilylene are summarized. Dedicated to the memory of Academician M. E. Vol'pin timed to his 75th birthday. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1063–1070, June, 1998.     

Reaction of a Dioxane Dichlorogermylene Complex with Compounds Containing C-H Bonds

The dioxane complex C₄H₈O₂·GeCl₂ reacts with compounds containing C-H bonds (C₆H₁₄, Me₃SiSiMe₃, C₄H₈O₂) with preferential formation of their trichlorogermyl derivatives.     

The hydrosilylation of propylene

The reactions of separate and competitive hydrosilylation of propylene with HSiCl₃, MeSiHCl₂, Me₂SiHCl, and MePh₂SiH in the presence of the Speier catalyst (SC) with different additives and a catalyst obtained from SC and propylene were studied. A mutual influence of the hydrosilanes in the competitive reactions was found. The influence of various additives to SC on the process was considered. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2048–2051, October, 1998.     

Gas-Phase Reaction of Anisole and Phenol with Tetrachlorogermane in the Presence of Hexachlorodisilane

Gas-phase reaction of anisole with tetrachlorogermane in the presence of hexachlorodisilane was studied. The major reaction products are chloro(phenoxy)silane, trichloro(phenoxy)germane, 1,1,3,3-tetrachloro-1,3-disila-2-oxaindane, and 1,1,3,3-tetrachloro-1,3-digerma-2-oxaindane. The same products are formed with phenol instead of anisole. A mechanism of the reactions of anisole with GeCl₄ and Si₂Cl₆ is proposed, that takes account of the formation in the reaction zone of dichlorosilylenes and dichlorogermylenes.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 606–609.Original Russian Text Copyright © 2005 by Chernyshev, Bykovchenko, Komalenko, Yakovleva, Simakina.     

Synthesis and application of organogermanium compounds

The application of organogermanium compounds (OGCs) to the creation of biologically active medicines with unique properties that possess a wide range of pharmacological actions, including the series of Panaxel drugs and Germavit mineral vitamin complex, is considered. Based on OGC, novel biologically active materials for medical technology were developed: dental flosses, retention surgical suture, bandages, and other products. The biological activity of OGC also allows to use them in perfumery and cosmetics industries. The methods for the synthesis of organogermanium compounds are described.     

Some regularities of chlorosilanes etherification

The influence of reagents, solvent polarity, and temperature on the etherification of chlorosilanes ClCH₂SiCl₃, VinSiCl₃, PrSiCl₃, and Ph₃SiCl with ethanol was studied. Influence of reaction temperature on the ratio of the synthesized alkoxysilane and related side-product siloxane is revealed. Use of excess alcohol is shown to increase the content of siloxane. Introduction of FeCl₃ does not affect the synthesis. Solvents are shown to influence the reaction rate: the rate constant increases with increasing ? parameter of the solvent. The rate constant of etherification of chlorosilanes with ethanol falls in the series: ClCH₂SiCl₃ > VinSiCl₃ > PrSiCl₃. An explanation of the regularities is suggested.     

Hydrogermylation of silyl-substituted ethylenes with trimethylgermane and trichlorogermane etherate

Investigation of the reaction of some vinylsilanes of the general formula Cl_3?n (CH₃) _n SiCH=CH₂ (n = 0,1,2,3) and 1,2-bis(trimethylsilyl)ethylene with trimethylgermane and trichlorogermane etherate was carried out. It was established that hydrogermylation only at the use of HGeCl₃·2Et₂O was sensitive to the nature of the substituting silyl groups in vinylsilanes. Nucleophilic mechanism of the reaction of trichlorogermane etherate with vinylsilanes is suggested.