Syntheses of arylsulfonyl-1,3,4-thiadiazoles

Reaction of sodium arylsulfinate with 2-aryl-5-chloro-1,3,4-thiadiazole gave 2-aryl-5-arylsulfonyl-1,3,4-thiadiazole (3) in good yield. Starting from readily available 2-amino-5-benzylmercapto-1,3,4-thiadiazole compound 7 was obtained in three steps in moderate yield. Reaction of compound 7 with sodium arylsulfinate afforded 2,5-diarylsulfonyl-1,3,4-thiadiazole ( 11 ). Oxidation of compound 10 with hydrogen peroxide in acetic acid gave 2-arylsulfonyl-5-benzylsulfonyI-1,3,4-thiadiazole ( 12 ), in high yield.