Copper(II)-Catalyzed and Chelation-Induced Remote C-H Halogenation of Quinolines under Neutral Conditions

Copper(II)-catalyzed highly regioselective halogenation of 8-acylaminoquinolines was reported in this study. The halogenation of 8-acylaminoquinolines proceeded smoothly in the presence of copper halide (CuBr2 or CuCl2) and potassium halide (KBr or KCl) as the catalyst and the halogen source, respectively, using oxygen in air as the terminal oxidant under neutral conditions to produce the corresponding C-5 position halogenated products in satisfactory to good yields.