Synthesis of 4,4-Disubstituted 1,3-Thiazol-5(4H)-thiones

Article abstract of DOI:10.1002/hlca.19860690217

An easy synthesis for the 1,3-thiazol-5(4H)-thiones 5, a class of heterocycles which have hitherto only been available with difficulty, is described.Reaction of 3-amino-2H-azirines 25 with thiocarboxylic acids at 0 deg yields monothiodiamides of type 20 (Scheme 6) which, on treatment with Lawesson reagent at 100 deg, undergo thiation and cyclization to give 5 in good yield.