“…However, under Cu(OAc) 2 /PhI(OAc) 2 system, in particularly, only single Cl, Br or I halogen was introduced successfully, when CuCl 2 , NaX, or I 2 was used alone as halogen source . Even though diverse C−X (X= Cl, Br, I) bonds may be formed with NaX reported by Zhang group, low chlorination yield limits its wide application. Moreover, other drawbacks are obvious, such as elevated temperature, acid or base additives, were required in these protocols.…”