A general and versatile synthesis of 3-phenylthio β-lactams as lead molecules for 3-methyl-2-azetidinones

Abstract

(Chemical Equation Presented) Ketene-imine cycloaddition using phosphorus oxychloride and benzenesulfonyl chloride under the described reaction conditions yielded trans 3-phenylthio 2-azetidinones in good yields. Desulfurization using Raney nickel and alkylation finally afforded trans 3-methyl-2-azetidinones in a stereoselective manner.