Chemistry of O-Silylated Ketene Acetals: A Mild and Convenient Synthesis of β-Lactam Antibiotics

Abstract

P-Amido sulfoxides (1) reacted with O-silylated ketene acetal (16) in dry acetonitrile in the presence of a catalytic amount of zinc iodide to give the 4-phenylthioazetidin-2-ones (17). Oxidation of 17 with m-chloroperbenzoic acid gave the corresponding sulfoxides (18), which were treated with 16 to give the azetidin-2-one esters (20), known precursors of PS-5-tvne carbapenem antibiotics. © 1991, The Pharmaceutical Society of Japan. All rights reserved.