Cyclic sulphones. Part XIX. Reactions of the 1,2,6-thiadiazine 1,1-dioxide system with some electrophiles

Abstract

Three 3,5-disubstituted 1,2,6-thiadiazine 1,1-dioxides have been shown to react with a number of electrophiles affording 4-substituted products. Halogenation, nitrosation, azo-coupling, and Mannich and Vilsmeier reactions have been performed, and nitration was also successful provided that the substrates were N-methylated. N-Methylation was conveniently performed with diazomethane. The behaviour of this heterocyclic sulphone is strikingly analogous to that of 2-pyrimidone.