Synthesis of β-Dimethylsulfonium- and β-Methylthio-Substituted Vinyl Triflates by Reaction of Acetylenes with Dimethyl Sulfide Ditriflate

Abstract

A one-pot synthesis of β-dimethylsulfonium-substituted vinyl triflates by the reaction of dimethyl sulfide ditriflate with acetylenes is described. β-Dimethylsulfonium-substituted vinyl triflates were found to exhibit unusual reactivity towards nucleophiles resulting in demethylation of sulfonium salts, but not substitution of triflate. Demethylation of these sulfonium salts with diethylamine gave the corresponding β-methylthio-substituted vinyl triflates. The possibility of thiophene derivative synthesis via triflic anhydride promoted cyclization of sulfoxide was studied.