Cyclization of acyl radical onto NC bond: Application in the synthesis of β-lactam

► Using DFT to study the regioselectivity in the cyclization of various 4-azahexenoyl radicals. ► Substituent with π-system at the C-terminal position favors 4-exo cyclization (i.e. β-lactam). ► This radical cyclization can be applied to the syntheses of β-lactam-fused bicyclic compounds.