Organophotoredox‐Catalyzed CDC Reactions for the Synthesis of Diverse Heterocycles via C─N and C─O Bond Formation under Visible Light Irradiation

Abstract An efficient construction of C═N and C─O bonds by the metal‐free organophotoredox catalyzed intramolecular cross‐dehydrogenative coupling of tertiary amines with amides, amines, and acids as nucleophiles is described. A series of 12,13‐dihydro‐6 H ‐isoquinolino[2,1‐a]quinazolin‐6‐one, 5,6‐dihydrobenzo[4,5]imidazo [2,1‐ a ]isoquinoline, and 4b,13‐dihydro‐6 H ,12 H ‐benzo[4,5] [1,3]oxazino[2,3‐a]isoquinolin‐6‐one derivatives were prepared in good to excellent yields. All the transformations proceeded smoothly under an oxygen atmosphere, serving as a clean oxidant. Moreover, the current approach was extended for the synthesis of the biologically active natural product, rutaecarpine.