Synthesis, characterization, and antioxidant activities of imine compounds

Monomeric complexes of the ligand H2L, with the general formula [M (HL2)(2)] with (M (II) = Co, Ni, Cu), have been synthesized and characterized by proton nuclear magnetic resonance (H-1-NMR), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), elemental microanalysis, metal content, magnetic moment and molar conductance measurements, molar conductance, and chloride containing. On the basis of experimental evidences, tetrahedral geometry has been proposed for prepared Schiff bases complexes. The geometry of the ligand and its complexes were confirmed by their optimized structures obtained from the computational study. Antioxidant activities of these compounds were evaluated against 1.1-diphenyl-2-picrylhydrazyl (DPPH) radical and were compared with standard natural antioxidant, ascorbic acid. The results reveal that these compounds exhibit excellent radical scavenging activities.