Reaction of Quinoxalin‐2‐ones with Difluorocarbene.

Abstract The reaction of quinoxalin-2-ones ( 1 ) with difluorocarbene derived from chlorodifluoro- methane(CHClF 2 ) has afforded 2-difluoromethoxyquinoxalines ( 2 ), 1-difluoromethyl- quinoxalin-2-ones ( 3 ) and 2-fluoroquinoxalines ( 4 ), and with difluorocarbene from dibromodifluoromethane (CBr 2 F 2 ) afforded 2-bromodifluoromethoxyquinoxalines ( 5 ), ( 2 ) and ( 4 ). Compounds 2 and 5 were readily converted into 4 under basic conditions. The reaction of 2-bromodifluoromethoxyquinoxaline ( 5a ) with poly(hydrogen fluoride) pyridine afforded 2-trifluoromethoxyquinoxaline ( 6a ).