Isothiazoles. Part 13: Synthesis of sulfamic esters, [1,2] thiazete S,S-dioxides, benzo[e][1,2]thiazine S,S-dioxides or triazoles by reaction of isothiazole dioxides with sodium azide

The reaction of sodium azide with 5-substituted 3-diethylamino-4-(4-methoxyphenyl)-isothiazole 1,1 dioxides is presented affording [2-cyano-1-diethylamino-2-(4-methoxyphenyl)-ethylidene]-sulfamic acid derivatives, 3-diethylamino-1,1-dioxo-4-(4-methoxyphenyl)-1,2-dihydro-[1,2]thiazete-4-carbonitrile, 3-diethylamino-7-methoxy-1,1-dioxo-1,4-dihydro-benzo[e][1,2]thiazine-4-carbonitrile or triazole derivatives. The outcome of the reaction strongly depends on C-5 substituent and the correct choice of the reaction conditions allows direction of the reaction towards the formation of the sulfamic acid esters or the [1,2]thiazete carbonitrile or the triazoles in satisfactory yield.