Visible-Light Photoredox Catalyzed C-N Coupling of Quinoxaline-2(1H)-ones with Azoles without External Photosensitizer

A visible-light photoredox catalyzed C-N coupling of quinoxaline-2(1H)-ones with azoles in the absence of external photosensitizer has been developed. The protocol employs commercially available pyrazoles and triazoles as amination reagents and shows wide substrate scope, providing the corresponding C3-position amination products in good yields and high regioselectivity under ambient conditions. Investigations indicate that the starting materials and products can act as photosensitizers avoiding use of additional photocatalyst in an autocatalytic manner. In addition,(1)O(2)coexists with O(2)(.-)from molecular oxygen (O-3(2)) via an energy transfer (ET) and single electron transfer (SET) process during the reaction.