A chemoselective thiocyanation of imidazothiazoles and 2-aminothiazoles with use of in situ generated N-thiocyanatosuccinimide (NTS) at room temperature is described. The protocol offers mild reaction conditions and high chemoselectivity for electrophilic substitution in imidazothiazoles over nucleophilic substitution. This method provides metal-free and easy conversion of imidazothiazoles and 2-aminothiazoles into their corresponding C-3 and C-5 thiocyanates, respectively, in good to excellent yield. The present protocol also offers the effective thiocyanation of bifunctional imidazothiazoles containing aliphatic –OH and C(sp2)–H bond functionalities.
Keywords
N-thiocyanatosuccinimide - thiocyanation - imidazothiazoles - 2-aminothiazoles - PEG-400