An environmentally benign procedure for the Cu-catalyzed cyanation of aryl bromides

The development of a general Cu-catalyzed synthesis of (hetero)aromatic nitriles from the corresponding aryl bromides and potassium hexacyanoferrate(II) is described. This novel protocol avoids the use of highly toxic alkali cyanides and precious palladium catalysts. Best results were achieved applying Cu(BF4)2·6H2O (0.1 equiv) and N,N′-dimethyl ethylenediamine (DMEDA; 1.0 equiv) in N,N-dimethyl acetamide (DMAc).