Synthesis of β-lactams from acetic acids and imines induced by phenyl dichlorophosphate reagent

Article abstract of DOI:10.1016/S0040-4020(01)96484-1

The development of a practical method for the preparation of vinylamino-β-lactams from Dane salts and Schiff bases is described. Among the reagents known to produce β-lactams from imines and acetic acids, only phenyl dichlorophosphate and 1-methyl-2-chloropyridinium iodide are suitable for the synthesis of vinylamino-β-lactams. Reaction of acetic acids with ethanolimine derivatives promoted by phenyl dichlorophosphate affords oxazolidines instead of β-lactams. Protection of the hydroxyl group as the trimethylsilyl ether in the starting Schiff bases provides a convenient route to the corresponding β-lactams instead of oxazolidines. Some observations on the scope of the method are made.