Azomethine imines, broadly known as 1,3-dipoles, efficiently produce synthetically and biologically significant dinitrogen-fused heterocycles via predominantly concerted or ionic pathways. Herein, we describe a radical-based annulation of azomethine imines utilizing visible-light photoredox catalysis for the first time. This strategy enables the synthesis of dinitrogen-fused saturated six-membered cyclic products that have traditionally been difficult to access. Notably, our process exhibits exceptional diastereoselectivity, controlled by the anomeric effect. Initial mechanistic investigations reveal a tandem process comprising intermolecular radical addition and intramolecular 6--trig cyclization. This work illustrates potential within the realm of visible-light-driven radical cyclization reactions involving azomethine imines.
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