Synthesis of 3-Alkyl-5-Allylamino-2-benzoylimino-1,3,4-thiadiazoles via Dimroth rearrangement

Abstract

A facile access to 3-Alkyl-5-N-Allylamino-2-N′-benzoylimino-1,3,4-thiadiazoles via Dimroth rearrangement is reported. Alkylation of 5-Allylamino-4-benzoyl-1,2,4-triazole-3-thione with alkyl halides in basic alcohol solution is regioselective. A mechanism for the formation of a 1,3,4-thiadiazole ring by 1,2,4-triazole recyclization is proposed. The obtained compounds were characterized by NMR, elemental analysis and X-ray diffraction analysis.