A New Cyclisation of Sulfenylated Dimethyl Sulfoxide and Thiosemicarbazone Adducts using Thionyl Chloride†

Abstract

Adducts (4a–d) obtained by nucleophilic addition of sulfenylated dimethyl sulfoxide derivatives (2a,b) to thiosemicarbazones (3a,b) undergo a new intramolecular cyclisation, involving deoxygenative demethylation, to yield 5-sulfenylated 4-aryl-2-thiocarbamoyl-1,2,3-thiadiazolidines (7a–d) on treatment with thionyl chloride.