| Popis: |
Electrochemical and chemical oxidation of (Et-Xan−), [Ni(Et-Xan-2] and [Ni(Et-Xan)3]− (Et-Xan− = C2H5OCS2 −) have been studied by Cyclic Voltammetry and in situ UV-Vis spectroscopy in acetonitrile at room temperature. Cyclic Voltammograms (CV) of Et-Xan− and Ni(Et-Xan)2 display one (0.00 V) and two (0.35 and 0.80 V) irreversible oxidation peaks, respectively, referenced to Ag/Ag+(0.10 M) electrode. However, CV of Ni(Et-Xan)3 − displays one reversible (-0.15 V) and two irreversible (0.35, 0.80 V) oxidation peaks, respectively, referenced to Ag/Ag+ electrode. The products of constant potential electrolysis at the first oxidation peak potentials of Et-Xan” and [Ni(Et-Xan>2] are the dimer of the oxidized ligand, (Et- Xan-2 and Ni2+ (sol); and that of Ni(Et-Xan)3]− are (Et-Xan)2 and [Ni(Et-Xan)2]. Chemical oxidation of Et-Xan− and [Ni(Et-Xan)3]− with iodine to (Et-Xan)2 and (Et- Xan)2/[Ni(Et-Xan)2], were also achieved. The oxidized ligand in the dimer form can be reduced to Et-Xan− with CN− in solution. Our data do not support the formation of Ni(III) species at any oxidation stage. |
