Synthesis and Structural Characterization of the Mononuclear Cobalt(II) Complex: {5,5′-Dihydroxy-2,2′-[o-phenylene-bis(nitrilomethylene)]diphenolato}cobalt(II) Dihydrate

Abstract

The Schiff base ligand H2L·C2H5OH derived from the condensation reaction between o-phenylenediamine and 2,4-dihydroxybenzaldehyde as well as its mononuclear complex [CoL]·2H2O have been synthesized and characterized by X-ray crystallography, IR, 1H NMR and UV–Vis analyses, and density functional theory (DFT B3LYP) calculations. The CoII ion has a slightly distorted square-planar coordination provided by tetradentate dianionic N2O2 ligand L2−. The spin state of the complex was determined as being S = 1/2. On the basis of DFT calculations, the UV–Vis absorption bands of the ligand can be assigned to the 1A1 → 1B2 (two) and 1A1 → 1A1 transitions, while for complex they correspond to the 2A2 → 2B1 (two) and 2A2 → 2A2 ones. Index Abstract The Schiff base ligand H2L·C2H5OH derived from the condensation reaction between o-phenylenediamine and 2,4-dihydroxybenzaldehyde as well as its mononuclear complex [CoL]·2H2O have been synthesized and characterized by X-ray crystallography, IR, 1H NMR and UV–Vis analyses, and density functional theory (DFT B3LYP) calculations.