Herein, we introduce an innovative approach employing a direct visible-light-excited Lewis acid-catalyzed 2σ + 3π cycloaddition reaction between bicyclo1.1.0butanes and α-vinyl azides via diradical intermediate. This transformation proceeds efficiently in the absence of any external photocatalyst produces versatile 2-azabicyclo3.1.1heptene derivatives with a broad substrate scope, achieving yields of up to 94% across 34 examples. The synthetic practicality was further demonstrated through a scaled-up reaction, and the transformation of the imidazole auxiliary into an ester group.
Du et al. (Tue,) studied this question.