1,2,4-Dithiazole-3-thiones and derivatives

5-Aryl-1,2,4-dithiazole-3-thiones may be made by sulfurization of N-aroyl-isothiocyanates, -thionocarbamates, or -dithiocarbamates. Attempts to produce 5-alkyl compounds failed, whereas an alternate cyclization of a reaction intermediate produced a 1,3-thiazine from cinnamoyl isothiocyanate. The mechanisms of the reactions are discussed briefly. The thiones readily form adducts with methyl iodide and reactive acetylenes. In the latter case, 1,3-dithiole derivatives are obtained.