Reactions of nucleophiles with some N-methyl-1,2,4-thiadiazolium salts

Abstract

N-Methyl salts were prepared from 3,5-disubstituted 1,2,4-thiadiazoles, the position of methylation was established (N-2 or N-4), and the reactions of the salts with a variety of oxygen, sulphur, nitrogen, and carbon nucleophiles were studied. Initial attack took place either at carbon (predominantly C-5) or at sulphur (S-1), depending on the nature of the nucleophile employed.