Photoinduced Reduction of Nitroarenes and Tandem C-N Cross-Coupling with Haloarenes.

An efficient photocatalytic C-N cross-coupling of nitroarenes with haloarenes has been developed using simple and cheap Ni(acac) 2 as a cocatalyst. The reaction is confirmed as a stepwise process: (1) metal free photoinduced reduction of nitroarenes into aniline derivatives and (2) photo- and Ni-catalyzed C-N cross-coupling of anilines with haloarenes. The reaction conditions are simple and mild, giving high-value diarylamines with good to excellent yields and good functional group tolerance.