Visible-Light-Induced Recyclable g-C3 N4 Catalyzed C–H Hydroxylation of Quinoxalin-2(1 H)-ones.

A visible-light-promoted hydroxylation of quinoxalin-2(1 H)-ones using recyclable graphitic carbon nitride (g-C3 N4) as a heterogeneous photocatalyst has been developed. This protocol enables the selective synthesis of various hydroxyl-containing quinoxalin-2(1 H)-ones in good to excellent yields under an ambient air atmosphere. Importantly, this heterogeneous catalyst can be used at least six times without significant loss of activity. [ABSTRACT FROM AUTHOR]