2,2′-Bipyridine based biologically active mixed ligand metal(II) complexes: Synthesis, characterization, DFT and antioxidant studies

Mixed ligand [CoL(bpy)], [NiL(bpy)], [CuL(bpy)] and [ZnL(bpy)] complexes were synthesized from Schiff base ligand L, metal(II) acetates of Co, Ni, Cu and Zn with 2,2′-bipyridine (bpy). The synthesized compounds were characterized using molar conductance, elemental analyses, 1H-NMR, FTIR and mass spectral studies. The geometry of metal complexes has been assigned by magnetic moment analysis and UV-vis spectral techniques. The X-band ESR spectra of [CuL(bpy)] complex in DMSO were recorded at room temperature and liquid nitrogen temperature. Grain size of metal complexes was predicted using Powder XRD. Computational DFT studies were performed using Gaussian 6.0 program package. HOMO-LUMO of L, optimized geometry, bond angle and bond length calculations were preceded at B3LYP/GENECP level with 6-31G (d,p) basis sets. Antimicrobial and antioxidant activities of complexes were evaluated.