Metal-Free C3 Hydroxylation of Quinoxalin-2(1H)-ones in Water

A practical protocol for the preparation of quinoxaline-2,3(1H,4H)-diones through direct C(sp(2))-H hydroxylation of quinoxalin-2(1H)-ones in recyclable DL-alpha-Tocopherol methoxypolyethylene glycol succinate solution (2 wt% in water) (TPGS-750-M/H2O) was developed. The target products were exclusively generated and could be collected through extraction and recrystallization.