N-unsubstituted sulfenamides by electrophilic amination of mercapto compounds

Potential mercapto compounds derived from electron deficient heterocycles as 2- and 4-thiouracils, pyridines and pyridine-1-oxide are aminated by the oxaziridine 1 to new sulfenamides (6, 9, 11 and 15 or the isothiazolo-pyridine 14) which add to phenylisocyanates forming sulfenylureas (7, 10, 12 and 16). Several other mercapto compounds gave disulfides. Attempts of oxidation of the sulfenamides and the sulfenylureas were unsuccessful. The methylmercapto compound 19 after amination was hydrolyzed to the sulfoxide 20.