Direct synthesis of methyldimethoxysilane from metallic silicon and methanol using copper(I) chloride catalyst

When the reaction of metallic silicon with methanol in the presence of a small amount of thiophene was carried out at 653 K, methyldimethoxysilane was formed together with trimethoxysilane and tetramethoxysilane, the selectivity for methyldimethoxysilane being 22%. Further adding a small amount of trioxane, trimer of formaldehyde, to the reaction system improved the selectivity for methyldimethoxysilane. This indicates that formaldehyde formed by the dehydrogenation of methanol takes part in methyldimethoxysilane formation. The reaction of silicon with ethanol also gave a 14% selectivity of ethyldiethoxysilane with a 43% silicon conversion.