Termination of Mn(III)-based oxidative cyclizations by trapping with azide

[GRAPHICS] The radicals formed in Mn(III)-based oxidative free-radical cyclizations of beta-keto esters and malonate esters can be trapped with sodium azide and Mn(ill) to give cyclic and bicyclic azides in 30-80% yield. Reduction of the azide gives bi- and tricyclic lactams.