Visible-Light Copper Nanocluster Catalysis for the C-N Coupling of Aryl Chlorides at Room Temperature.

Activation of aryl chlorides in cross-coupling reactions is a long-standing challenge in organic synthesis that is of great interest to industry. Ultrasmall (<3 nm), atomically precise nanoclusters (NCs) are considered one of the most promising catalysts due to their high surface area and unsaturated active sites. Herein, we introduce a copper nanocluster-based catalyst, [Cu 61 (S t Bu) 26 S 6 Cl 6 H 14 ] (Cu 61 NC) that enables C-N bond-forming reactions of aryl chlorides under visible-light irradiation at room temperature. A range of N -heterocyclic nucleophiles and electronically and sterically diverse aryl/hetero chlorides react in this new Cu 61 NC-catalyzed process to afford the C-N coupling products in good yields. Mechanistic studies indicate that a single-electron-transfer (SET) process between the photoexcited Cu 61 NC complex and aryl halide enables the C-N-arylation reaction.