Photochemical Synthesis of Anilines via Ni-Catalyzed Coupling of Aryl Halides with Ammonium Salts

Easy, efficient, and economic synthesis of anilines remains an important challenge in synthetic chemistry. In this study, a Ni(OAc)2-bipyridine complex is shown to readily catalyze the amination of aryl halides with ammonium salts under direct excitation of light, allowing a broad array of aryl chlorides and bromides to be converted into the corresponding primary (hetero)arylamines in the absence of an external photosensitizer. Late-stage modification of drug molecules and 15N-labeling of primary aryl amines are also demonstrated with a number of examples. Photoinduced generation of Ni(I)-bipyridine species is believed to be the key step in the reaction, enabling a Ni(I)/Ni(III) cycle for catalytic turnover.