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

The reaction of warm EtOH solutions of FeX3 nH2O (X = Cl, NO3) with tridentate ONX (X = O, S, N) pyridoxal semi-, thiosemiand S-methylisothiosemicabazones (H2L 1, H2L 2, H2L 3, respectively) yielded high-spin octahedral monoand bis(ligand) complexes of the formula Fe(H2L )Cl2(H2O) Cl, Fe(HL )2 Cl nH2O and Fe(H2L 3)(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.