The title complex NiL2+ is oxidized in aqueous solutions in the pH range 3-7 in the presence of stabilizing anions X, X = HCO2-, SO42-, and H2PO4-, by HO2· free radicals to NiIIILX2. The dependence of the rate of formation on [NiL2+] and X indicates that the H02· radical reacts with a [NiL2+] complex in the ion pair [NiL2+, X], forming the final products. The volumes of activation of the oxidation processes were measured; an analysis of the data indicates that the ion pairs involved are contact ion pairs. The results indicate that in the presence of appropriate transition-metal complexes the superoxide free radical is a potent oxidizing agent and suggest that this might cause some of the aspects of its toxicity.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry