Overcoming the Low Reactivity of Aryl Chlorides: Amination via Reusable Polymeric Nickel–Iridium Dual Catalysis under Microwave and Visible Light

The amination of aryl chlorides was facilitated via dual activation using polymeric nickel and iridium catalysts under microwave and visible-light irradiation. For this, a polymeric iridium complex, poly-[Ir(ppy)2(dabpy)], was prepared as a stable and reusable photocatalyst, which was characterized by using nuclear magnetic resonance spectroscopy, elemental analysis, cyclic voltammetry, and UV–vis absorption–emission spectroscopy. The carbon–nitrogen bond-forming reaction of aryl chlorides and amines afforded up to a quantitative yield using a combination of poly-[Ir(ppy)2(dabpy)] and a polymeric nickel catalyst (P4VP-NiCl2), with only 0.03 mol % of iridium and 0.2 mol % of nickel sufficing to catalyze the reaction. Notably, the reaction displayed a broad substrate scope, accommodating primary, secondary, and aromatic amines, as well as both electron-rich and electron-deficient aryl chlorides. Furthermore, both the nickel and iridium catalysts could be recovered and reused multiple times without significant losses of activity. This approach can be used for the synthesis of several biologically active molecules