Convenient Preparations of 3,5-Disubstituted 1,2,4-Thiadiazoles by Oxidative Dimerization of Thioamides

Abstract

Abstract 3,5-Disubstituted 1,2,4-thiadiazoles 2 were prepared by reaction of thioamides 1 with DMSO in the presence of such an electrophilic reagent as 1-methyl-2-chloropyridinium iodide, benzoyl chloride, acetyl chloride, hydrochloric acid, or trimethylsilyl chloride in organic solvents at room temperature in high yields. Thiadiazoles 2 were also obtained by reaction of 1 with NBS at room temperature in high yields. Thioamide S-oxides reacted with electrophilic reagents at room temperature to give the corresponding thiadiazoles 2 in high yields.