Trapping of thiaziridinimines with thiocarbonyl compounds

Abstract
Thermolysis of 4‐benzyl‐5‐tosylimino‐1,2,3,4‐thiatriazoline at 60–70° in the presence of representative C = S unsaturated compounds furnished 1,2,4‐dithiazolidin‐5‐imines in moderate yields. The reaction is assumed to proceed via the inlermediacy of an unstable thiaziridinimine which is trapped by the C=S compound in a regiospecific manner. Among the thiocarbonyl compounds used are p,p′‐dimethoxythiobenzophenone, xanthates and 3‐benzylrhodanine, the latter giving rise to a spiro adduct.