Copper-Catalyzed C3-H Difluoroacetylation of Quinoxalinones with Ethyl Bromodifluoroacetate

A copper-catalyzed direct C-H difluoroacetylation of quinoxalinones at the C-3 position with ethyl bromodifluoroacetate has been developed. In this reaction, diverse difluoroacetylated quinoxalin-2(1H)-ones with a wide range of functional groups could be obtained in moderate to good yields, using cheap, commercially available reagents. This protocol would offer a meaningfully synthetic method for pharmacologically interesting difluoroacetylated quinoxalin-2(1H)-one derivatives.