Transition metal complexes with thiosemicarbazide-based ligands. Part 47. Synthesis, physicochemical and voltammetric characterization of iron(III) complexes with pyridoxal semi-, thiosemi- and S-methylisothiosemicarbazones

Abstract

The reaction of warm EtOH solutions of FeX3·nH2O (X = Cl, NO3) with tridentate ONX (X = O, S, N) pyridoxal semi-, thiosemi- and S-methylisothiosemicabazones (H2L1, H2L2, H2L3, respectively) yielded high-spin octahedral mono- and bis(ligand) complexes of the formula [Fe(H2L1-3)Cl2(H2O)]Cl, [Fe(HL1,2)2]Cl·nH2O and [Fe(H2L3)(HL3)](NO3)2·H2O. The compounds were characterized by elemental analysis, conductometric and magnetochemical measurements, IR and UV-Vis spectra. Besides, a detailed voltammetric study of the complexes was carried out in DMF solution in the presence of several supporting electrolytes, to characterize the nature of the electrode processes and solution equilibria.

Keywords

• iron(III) complexes
• pyridoxal semi-
• thiosemi- and isothiosemicarbazones
• physicochemical and voltammetric studies