Chlorotrimethylsilane-nitrate salts as oxidants: direct oxidative conversion of thiols and disulfides to sulfonyl chlorides

A mixture of nitrate salt and chlorotrimethylsilane is found to be a mild and efficient reagent for the direct oxidative conversion of thiols (1) and disulfides (2) to the corresponding sulfonyl chlorides (3) in excellent yields through oxidative chlorination. Sulfides and sulfoxides were also found to undergo oxidation to sulfones under similar reaction conditions. In most cases these reactions are highly selective, simple, and clean, affording products in high yield and purity.