New organocobaloxime derivatives – Synthesis, characterization, catalase-like activity and DFT studies

Abstract

New organocobaloxime derivatives of the types [Co(HL)2(Bz)Py] and [CoL2(Bz)PyB2F4] [H2L = 4-(4-chlorophenylamino)biphenylglyoxime; Bz = Benzyl; Py = Pyridine] were synthesized and characterized by elemental analysis, molar conductance, FT-IR, 1H NMR and magnetic susceptibility measurements. The structural and vibrational spectroscopic data of the molecule in the ground state were calculated by the density functional method using the 6-31G(d) basis set. Isotropic chemical shifts (1H and 13C NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. In addition, the thermal decomposition of complexes with H2L was studied in nitrogen atmosphere. The IR spectra indicated that the complexes coordinate through the N atom of the oxime group of the ligand. The diamagnetic susceptibilities of the complexes indicated that they are diamagnetic (low-spin d6 octahedral). The catalase-like activities of the complexes for the disproportionation of hydrogen peroxide were investigated in the presence of imidazole. The redox behaviors of the ligand and its complexes were investigated by cyclic voltammetry at the platinum electrode in DMF.