Mn(III)-promoted sulfur-directed 4-exo-trig radical cyclization of enamides to β-lactams

Article abstract of DOI:10.1016/S0040-4020(98)83055-X

The synthesis of β-lactams vinylated at C-4 from N-(3-phenylthio-1- alkenyl) amides was carried out by Mn(III)-promoted 4-exo-trig radical cyclization followed by β-fragmentative loss of phenylthiyl radical. The effects on the reaction course of different substituents both on enamidic nitrogen atom or double bond were analyzed. The overall reaction was stereoselective, leading to trans azetidinones.