Synthesis, structure and spectroscopic properties of the trinuclear cobalt(II) and nickel(II) complexes based on 2-hydroxynaphthaldehyde and bis(aminooxy)alkane.

A new Salen-type bisoxime ligand, 2,2'-[ethylenedioxybis(nitrilomethylidyne)]dinaphthol (H2L) and its corresponding cobalt(II) and nickel(II) complexes, [{CoL(DMF)}2(OAC)2Co] and [{NiL(H2O)}2(OAc)2Ni]⋅2C2H5OH have been synthesized, and characterized by elemental analyses, IR spectra, UV-vis spectra, TG-DTA and molar conductance measurements, etc. The X-ray crystal structure studies reveal that the cobalt(II) and nickel(II) complexes are symmetric trinuclear structures. All of the M(II) (Co(II) or Ni(II)) ions for the cobalt(II) or nickel(II) complexes are six-coordinated and have slightly distorted octahedral coordination geometries.