| Research Abstract |
Synthesis of polysilanes by electrochemical method has been investigated. Cathodic reduction of chlorosilanes with the use of copper electrode system in dimethoxyethane in an undivided cell afforded some lower homologues of polysilanes such as disilanes, trisilanes, tetrasilanes, and pentasilanes selectively in high yields. Similar electrolyses of 1,2-bis(chloromethylphenylsilyl)ethane and 1,2-bis[chloromethyl(rho-tolyl)silyl]ethane afforded poly(disilanylene)ethylenes with high molecular weights, in which no siliconoxygen bonds in the polymer backbone are included. Moreover, reduction of 1,2-bis- (chloromethylphenylsilyl)benzene afforded poly(disilanylene)phenylene.
A highly selective synthesis of chlorosilanes from hydrosilanes has also been investigated. The reaction of dimethylphenylsilane, methyldiphenylsilane, and di(n-butyl)- methylsilane with 2 equiv of copper(II) chloride and a catalytic amount of copper(I) iodide afforded the respective triorganochlorosilanes. Similar reactions of polyhydrosilanes such as diethylsilane, methylphenylsilane, phenylsilane, 1,1,2,2-tetraethyldisilane, and 1,2- dimethyl-1,2-diphenyldisilane with 2 equiv of the CuCl_2(CuI) reagent gave the corresponding monochlorinated hydrosilanes selectively, while treatment with 4 equiv of the reagent afforded dichlorosilanes as the sole product.
|
