Reducible Drug Pyrazinamide as a Powerful Ligand to Assist Copper (II)‐Catalyzed N‐Arylation

ABSTRACT Herein, pyrazinamide (L1) was used as a powerful ligand to promote a CuSO 4 ‐catalyzed reaction between aryl halides and imidazole (HID) under mild conditions, generating various N‐arylation products in good to excellent yields. The findings indicate that CuSO 4 was reduced and coordinated with L1 to form [Cu I L1], which activated ArX to produce [ArCu I L1X] through oxidative addition. This intermediate subsequently underwent reductive elimination to form N‐arylation products, with [ArCuILID] being generated from a reaction between [ArCuIL1X] and HID. This method was successfully extended to the synthesis of 2‐phenylindole and pyrrolo[1,2‐a]quinoxaline under mild conditions. The method significantly enhances the efficiency and cost effectiveness of C‐N coupling reaction.