Copper(II) complexes of acid amide derivatives of 2-aminopyridine and an exogenous ligand

The bidentate ligands, 2-[(N-acetyl)aminopyridine] (AAPH, A) and 2-[(N-benz oyl)aminopyridine] (BAPH, B) have been used to synthesize copper(II) comple xes including an exogenous ligand X (X = AcO-, HCO2-, N-3(-) and benzimidaz ole). The complexes were characterized by elemental analysis, electronic an d vibrational spectroscopy, magnetic and e.s.r. studies. E.s.r. parameters and visible spectra indicated that all the complexes are monomers and exist in distorted octahedral geometry except for benzimidazole. With benzimidaz ole as an exogenous ligand, a five coordinate complex is formed.