Sulfur-directed regioselective radical cyclization leading to β-lactams: Formal synthesis of (±)-PS-5 and (+)-thienamycin

Article abstract of DOI:10.1021/jo00110a035

A new method for the synthesis of β-lactams by tributyltin hydride (Bu₃SnH)-mediated radical cyclizations of N-ethenyl-α-bromo amides bearing sulfur-substituent(s) at the terminus of the N-vinylic bond is described. N-[2-(Phenylthio)ethenyl]-α-