Asymmetric Radical Bicyclization of Allyl Azidoformates via Cobalt(II)-Based Metalloradical Catalysis

Cobalt(II)-based metalloradical catalysis has been successfully applied to radical bicyclization of allyl azidoformates to construct aziridine/oxazolidinone-fused bicyclic structures. The Co(II) complex of D 2 -symmetric chiral amidoporphyrin 3,5-Di t Bu-QingPhyrin has been identified as an effective metalloradical catalyst for the intramolecular radical aziridination of this type of carbonyl azides, allowing for high-yielding formation of synthetically useful chiral 3.1.0-bicyclic aziridines with high diastereo- and enantioselectivity.