A new general synthesis of 2-(N-mono- and N-di-substituted amino)thiazoles

Although α-mercapto ketones react with cyanamides to give substituted 2-aminothiazoles the yields are satisfactory in only the simplest cases. However, a range of 2-aminothiazoles with substitutents on the ring or the exo-nitrogen atom was obtained efficiently by the following one-pot procedure: a solution of an α-mercapto ketone anion was generated by treating an O-ethyl S-2-oxoethyl dithiocarbonate with piperidine at 20 °C, a cyanamide was added, and the solution was heated for 3–6 h.