ketenes in the Staudingerreaction. On the basis of the reactions of S-phenyl diazothioacetate with imines under the catalysis of Rh 2 (OAc) 4 a method for the synthesis of 3-phenylthio β-lactam derivatives has been developed previously. In this paper, a more convenient and improved procedure was achieved, which simplified the synthesis of S-phenyl diazothioacetate and made the reaction work well without