One-Pot Synthesis of 5-Acyl-1,2,3-Thiadiazoles from Enaminones, Tosylhydrazine, and Elemental Sulfur under Transition-Metal-Free Conditions

I-2/dimethyl sulfoxide (DMSO)-mediated C-S, S-N, and C-N bond cross-coupling cyclization reaction for the synthesis of 5-acyl-1,2,3-thiadiazoles from enaminones, tosylhydrazine, and elemental sulfur has been developed under transition-metal-free conditions. This strategy is operationally simple, compatible with a wide range of functional groups, and provides the desired products in moderate to excellent yields.