Regioselective one pot synthesis of 2-alkyl/aryl-4H-benzo[1,4]thiazine-3- one via microwave irradiation

Abstract

A series of 2-alkyl/aryl-4H-benzo[1,4]thiazine-3-ones have been synthesized by microwave irradiation of ethyl-2-bromo-2-alkyl/aryl acetate and 2-amino thiophenol in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene and N-methylpiperidine. All compounds were characterized by 1H NMR, 13C NMR and elemental analyses, and by X-ray crystallography in the case of 2-methyl-4H-benzo[1,4]thiazin-3-one.