Preparation of novel 1,2,4-thiadiazoles by cyclization with 4-methylbenzenesulfonyl cyanide (tosyl cyanide)

The preparation of 1,2,4-thiadiazoles with a di-tert-butylphenol substituent at the thiadiazole 3-position is described. A thermally generated nitrile sulfide was reacted with tosyl cyanide in a 1,3-dipolar cyclization reaction to provide a thiadiazole intermediate containing a labile 5-tosyl substituent.