3 COCl 2 1 step for the formation of a-azido@-lactams which eventually were transformed to penicillin^,^#^ cephalosporins, 68 nocardicin: and a number of their analogues. 1 However, very few reports describe the synthesis of 3-alkyl, 3-alkylidene, or 3-acyl P-lactams based on the acid chlorideimine cycloaddition reaction. 1 Synthesis of a-alkyl or a-acetyl p-lactams became an important target after the discovery of carbapenem antibiotics, namely, PS-5, ...
