Copper-Catalyzed Coupling of N-Acyl-N′-Substituted Hydrazines with (Hetero)aryl Chlorides/Bromides

The coupling of N-acyl-N'-substituted hydrazines with (hetero)aryl bromides and chlorides is efficiently catalyzed by CuI/4-hydroxy picolinamide and Cu(OAc)₂/6-hydroxy picolinohydrazide, respectively. Under these conditions, a broad range of (hetero)aryl halides and N-acyl-N'-substituted hydrazines react smoothly at 80-120 °C, affording the corresponding products in good to excellent yields in most cases.