Synthesis, Cyclic Voltammetry and Chronoamperometry Studies of Cobalt(II) Complexes with Tridentate Schiff Base Ligands

Abstract

Tridentate Schiff base ligands were prepared by the condensation reaction of anthranilic acid with salicylaldehyde, furfural, thiophen-2- carboxaldehyde and pyridine-2-carboxaldehyde in ethanol. Cobalt(II) complexes of related Schiff base ligands were prepared by the reaction of the respective ligand with cobalt(II) acetate. The prepared ligands and oxalato-bridged cobalt complexes have been characterized by UVvis, IR and ¹H NMR spectral data and elemental analysis. In all the cobalt(II) complexes it is supposed that the central metal has five coordination number and coordinated by a tridentate Schiff base ligand and two oxygen atoms of the oxalate ligand. The electrochemical properties of four Schiff base complexes have been investigated in the presence of tetrabutyl ammonium perchlorate as supporting electrolyte and by using a glassy carbon (GC) electrode. It has been found that all the cobalt complexes shows Co(II) oxidation process irreversibility. Cyclic voltammetry studies indicated that these processes are diffusion-controlled reactions. The obtained data from cyclic voltammetry and chronoamperometry studies showed that, the total limiting current of each of the studied compounds corresponds to one-electron transfer process.