A new method for simple and practical synthesis of diaryl-substituted arenes using potassium aryltriolborates was developed. Double-cross-coupling of dibromo arenes with aryltriolborates was carried out in the presence of a palladium catalyst, such as Pd (OAc) 2, Pd (PPh3) 4 or Pd (OAc) 2/BIPHEP. The use of CuCl (40 mol%) with a palladium catalyst was found to be highly effective to give diaryl-substituted aromatic compounds in good ...