Visible-Light-Induced Catalyzed C─H/N─H Cross Coupling of Quinoxalin-2(1H)-ones with Aliphatic Amines Using Mesoporous Graphitic Carbon Nitride

Abstract

In this study, we report a visible-light-induced catalyzed C─H/N─H cross coupling of quinoxalin-2(1H)-ones with aliphatic amines using DABCO (1,4-diazabicyclo[2.2.2]octane) assisted mpg-C₃N₄ (mesoporous graphitic carbon nitride). This reaction yields 3-aminoquinoxalin-2(1H)-ones in moderate to high yields under room temperature conditions in tetrahydrofuran as solvent and O₂ as the sole oxidant. This method displays a good functional group tolerance, requires mild reaction conditions, and enables easy recovery and reuse of the photocatalyst (4 recycles). This pathway to amination, which is predicated upon the use of DABCO as both a base and an electron transfer agent, reveals through a preliminary mechanistic investigation that the reaction involves a radical process.