Organo‐photocatalytic Synthesis of 6‐β‐Disubstituted Phenanthridines from α‐Diazo‐β‐Keto Compounds and Vinyl Azides

Abstract An efficient organo‐photocatalytic method for the synthesis of 6‐ β ‐disubstituted phenanthridines has been developed. The reaction documents unprecedented generation of enolate vinyl radicals from corresponding diazo compounds in the presence of photocatalyst Rh‐6G. Subsequent trapping of these radical intermediates by o‐aryl vinyl azides followed by intramolecular cyclization affords the final products in excellent yields and regioselectivity. The reaction is notable for its mild conditions, high yields and wide substrate scope.