Organometallic reactions. Addition reactions of benzenethiol to unsaturated systems catalysed by trimethyl(phenylthio)-silane or -stannane

Abstract

Trimethylphenylthiosilane has been shown to catalyse the addition of benzenethiol to isocyanates, isothiocyanates, activated double and triple bond, and ketens. This silicon catalyst appears much more effective than the tin and lead counterparts, for most of the systems investigated.

The slow formation at room temperature of the 1 : 1 adduct between the catalyst and the unsaturated system, and the low reactivity of the adduct itself towards benzenethiol exclude the intermediate formation of an insertion product in the catalytic process. A probable mechanism for these reactions is presented.