Synthesis and characterization of nickel(II) complexes of a tetraaza macrocycle containing axial ligands

Abstract

The octahedral complexes [NiLX 2] (X=OH 2 ( 1), ONO − ( 2) and NCO − ( 3); L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0 1.18,0 7.12]docosane) have been prepared and characterized by X-ray crystallography. The crystal structures of the [NiLX 2] complexes have an axially elongated octahedral geometry with two axial ligands and adopt the trans-III configuration. Magnetic moments, electronic spectra and redox potentials of the [NiLX 2] complexes also reveal a high-spin octahedral geometry, which is reflected by the nature of the axial ligands.