Method for preparing hydrogen silane by using calcium hydride to conduct reduction on chlorosilane

Abstract

The invention discloses a method for preparing hydrogen silane by using calcium hydride to conduct reduction on chlorosilane and belongs to the technical field of chlorosilane reduction. The problemsof harsh reaction conditions, low reaction speed and the like of chlorosilane reduction through CaH2 in the prior art are solved. In an organic solvent, under catalysis of a catalyst, calcium hydrideis used as a reducing agent, and chlorosilane is reduced into hydrogen silane; the catalyst is borane or borohydride or lithium aluminum hydride, and the organic solvent is tetrahydrofuran or diethylene glycol dimethyl ether or other ether solvents. The method can be applied to hydrogen silane preparation through chlorosilane reduction.

Description

technical field [0001] The present invention relates to the reduction of a kind of chlorosilane, relate in particular to a kind of calcium hydride (CaH 2 ) method for preparing hydrosilane by reducing chlorosilane. Background technique [0002] Hydrosilane is a silicon compound containing Si-H bonds in its molecule, which is an important functional monomer and has a wide range of uses. [0003] In the prior art, the preparation method of hydrosilane (containing chloroalkylhydrosilane) mainly adopts the reduction method, through the reaction of chlorosilane or alkoxysilane with abundant sources and a strong reducing agent, the chlorosilane or alkoxysilane on the Reduction of chlorine or alkoxy groups in whole or in part to H yields silicon hydrides. The reduction method has abundant raw materials, more types of hydrosilanes, and higher yields, and usually can retain unsaturated groups such as vinyl groups, and has wider adaptability. [0004] In the reduction method, the r...

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Problems solved by technology

In 1971, R.Calas et al. reported adding CaH 2 The amount of 5% (mol fraction) AlCl 3 can make CaH 2 Restore Me 3 The yield of SiCl can reach more than 80%; but the catalyst cycle can only be realized when it is higher than 270°C, and the temperature of the reaction system is very high

In 2007, A. Tsuhako et al. found that ZnCl 2 When present, CaH 2 Phenyldimethylsilane can be reduced, and the yield of product phenyldimethylsilane is 83%; ZnCl-free 2 When the reaction does not occur, it is confirmed that the ZnCl 2 However, the application of this catalytic reduction system is relatively narrow, such as for ClCH 2 SiMeCl 2 , ClCH 2 SiCl 3 Then there is no effect and the target product cannot be obtained

GotzKoerner et al. reported that ball milling, ultrasonic and other mechanical activation methods can be used to reduce organopolysiloxanes containing terminal Si-Cl to Si-H-containing organopolysiloxanes under relatively mild conditions of cheap metal hydrides. It does have a better effect on LiH, but on CaH 2 The effect of using only mechanical activation is often still difficult to reach a practical level

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