The reaction of copper(II) complexes of macrocyclic dioxotetraamines with hydroxyl free radical—A kinetic study by pulse radiolysis

Abstract

The copper(II) complexes of three dioxotetraamines were oxidized rapidly by hydroxyl free radical .OH produced by pulse radiolysis at pH 7.4. The formation and disappearance of copper(III) complexes were followed by electronic spectroscopy. The formation of Cu II complexes obeyed pseudo-first order reaction and their disappearance obeyed first order reaction. The oxidation rates of Cu II complexes by .OH have the following sequence: [Cu(npt)] > [Cu(dt)] ≈ [Cu 2(bdt)]. The formation and disappearance constants are in the following range: k t = 1.73 × 10 10−1.19 × 10 10, k d = 3.99 × 10 3−1.24 × 10 4.