Visible-Light-Induced C-3 Difluoroalkylation of Quinoxalin-2(1H)-ones with Difluoroiodane(III) Reagents under Catalyst-Free Conditions

A visible-light-induced radical difluoroalkylation of quinox-alin-2(1H)-ones by hypervalent-iodine-based reagents was developed. To facilitate the final oxidative step, [bis(trifluoroacetoxy)iodo]benzene (PIFA) was employed as an oxidant. Moreover, a one-pot protocol for this transformation was realized by generating the difluoroalkylation re-agent in situ. The readily accessible reagents and the mild reaction conditions make this reaction an alternative and practical strategy for the synthesis of C(3)-difluoroalkylated quinoxalin-2(1H)-ones.