Hydrogen-abstraction reactions from silanes. Part II. The reactions of methyl radicals with trifluorosilane, trimethylsilane, dimethyldichlorosilane, and trimethylchlorosilane

Abstract

The following Arrhenius parameters have been determined by photolysing azomethane in admixture with the organosilicon compound in the gas phase: [graphic omitted]

These results confirm the trend, previously reported, that the high reactivity of silanes in free-radical reactions arises from abnormally high A-factors and that the activation energies are not indicative of particularly weak Si–H and C–H bonds. The results are considered in term of information available on bond dissociation energies in silicon compounds and tentative suggestions are made to account for the high A-factors.