Res. Chem. Intermed.
, Vol. 32, No. 3–4, pp. 317–330 (2006)
Also available online - www.vsppub.com
Intermediacy of silylene and germylene in direct synthesis
of organosilanes and organogermanes
Department of Applied Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku,
Tokyo 152-8552, Japan
Received 1 March 2005; accepted 2 July 2005
Abstract—In the direct synthesis of silicon compounds by reactions of elemental silicon with methyl
chloride, methanol and hydrogen chloride, silylene formed on surface of silicon grains during the
reaction is an intermediate. The reaction of surface silylene with a variety of unsaturated hydrocarbons
provides new direct synthesis of organosilanes. In the direct synthesis of methylchlorogermanes
from elemental germanium, surface germylene is not an intermediate, while tetrachlorogermane
is synthesized by the direct reaction of germanium with hydrogen chloride via dichlorogermylene
intermediate. Various unsaturated hydrocarbons or organic chlorides added to the system of
tetrachlorogermane synthesis give new methods for the synthesis of organogermanes.
Keywords: Direct synthesis; silicon compounds; silylene; germylene; organogermanes.
In the silicon industry, dimethyldichlorosilane (1) is produced in the largest scale
as a raw material for synthesizing silicone polymers [1, 2]. Methylchlorosilanes
(1, 2, 3), mainly dimethyldichlorosilane (1), are obtained directly from elemental
silicon reacting with methyl chloride using copper catalyst [1–3]:
This reaction is called “direct synthesis” because of the direct formation from
elemental silicon. Various organic halides, such as ethyl chloride , allyl
chloride  and chlorobenzene [3, 5], besides methyl chloride, can be used for
direct synthesis .
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