Synthesis and characterization of 2-amino5-benzoylbenzimidazole complexes of manganese(II) and cobalt(II)

Several complexes of 2-amino-5-benzoylbenzimidazole (ABBI) with Mn(II) and Co(II) using different anions, Cl-, Br-, I-, NO3-, CH3COO-, HCOO-, ClO4- and SO42- have been isolated as stable, non-hygroscopic solids and cahracterized systematic analytical procedures such as cation-anion estimations, elemental analyses, conductivity, magnetic suscepubility and spectral studies have been employed to elucidate the structure and geometry of the complese. The analytical data are in accordance with the composition, [M(ABBI)(2)X-2] where M = Co(II) or Mn(II) and X = Cl, Br-, I-, NO3-, CH3COO-, HCOO-, ClO4- and SO42-. The overall investigations confirm the bidenticity of the ligand, the coordinated nature of the anions and the distorted octahedral geometry of all these complexes studied.