Complexation of a Nickel(III) Macrocyclic Complex by Sulfate Ion. A Pulse Radiolytic Study
Date of Original Version
The kinetics of oxidation of Ni11[meso-Me6aneN4] (NiL2+) to Ni(III) by OH radical and subsequent complexation by sulfate ion have been studied in acidic aqueous media at 22°C and μ=0.01-0.3 M by the pulse radiolytic technique. Results indicate that NiL3+hydrolyzes with a pK+3.7±0.2 but that, at least up to pH 5.2, substitution by SO42- occurs only on the unhydrolyzed species with a rate constant of 1X106 M-1 s-1 at μ=0.03 M. The equilibrium constant for sulfate complexation is 3.0X104 M-1 at μ=0.03 M and the product of the reaction is identical with the stable NiLSO4+species produced by the electrochemical oxidation of NiL2+in sulfate media. The results demonstrate the stabilization of NiIII by sulfate complexation. © 1979, American Chemical Society. All rights reserved.
Publication Title, e.g., Journal
Cohen, Haim, Dan Meyerstein, Dan Meyerstein, Louis J. Kirschenbaum, Esther Zeigerson, Moshe Jaacobi, Efrat Fuchs, Gregory Ginzburg, and Louis J. Kirschenbaum. "Complexation of a Nickel(III) Macrocyclic Complex by Sulfate Ion. A Pulse Radiolytic Study." Inorganic Chemistry 18, 10 (1979). doi: 10.1021/ic50200a026.