Synthesis, structure and properties of ternary copper(II) complexes of ONO donor Schiff base, imidazole, 2,2′-bipyridine and 1,10-phenanthroline

Reaction of copper(II) salt with salicylidene anthanilic acid (SAA), a tridentate ligand and imidazole (ImH), a monodentate ligand or bidentate polypyridyl ligands like 2,2′-bipyridine (bipy) or 1,10-phenanthroline(phen) in MeOH:MeCN (1:1 V/V) yields [Cu(SAA)(ImH)] (1), [Cu(SAA)(bipy)]CH3CN (2) and [Cu(SAA)(phen)] (3) in ∼80% yield. These complexes were characterized by elemental analysis, magnetic susceptibility, X-band e.p.r., electronic spectroscopy and cyclic voltammetry. All the reported complexes show g∥ > g⊥ > 2.0023 and G   values falling within the range of 2–4 are consistent with a dx2-y2dx2-y2 ground state in a square planar or square pyramidal geometry. Single crystal X-ray analysis of 1 has revealed the presence of a distorted square planar geometry (N2O2) and 2 has revealed the presence of distorted square pyramidal (4 + 1) geometry. In both structures the ONO Schiff base occupies the basal plane. Magnetic susceptibility measurements at room temperature were in the range 1.79 ± 0.01 BM. Superoxide dismutase (SOD) activity of the present complexes were also measured.

Graphical abstractThree new complexes [Cu(SAA)(ImH)] (1), [Cu(SAA)(bipy)] CH3CN (2), [Cu(SAA)(phen)] (3) were characterized by elemental analysis, magnetic susceptibility, X-band e.p.r., electronic spectroscopy and cyclic voltammetry. Single crystal X-ray analysis of (1) has revealed the presence of a distorted square planar geometry (N2O2) and (2) has revealed the presence of a distorted square pyramidal (4+1) geometry. In both structures the ONO Schiff base occupies the basal plane. Magnetic susceptibility measurements at room temperature were in the range 1.79 ± 0.01 BM. Superoxide dismutase (SOD) activity of the present complexes were also measured and discussed.Figure optionsDownload full-size imageDownload as PowerPoint slide