Journal Article

Inner sphere oxidation of N,Nâeuro²-ethylenebis(isonitrosoacetyleacetoneimine)copper(II) by N-bromosuccinimide in aqueous weakly acidic solutions

Eltayeb, Mohamed A-z, Salih, Isam M, Aljaber, Amina S, Sulfab, Yousif

2013

Overview

(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) The kinetics of oxidation of N,Nâ[euro]²-ethylenebis(isonitrosoacetyleacetoneimine)copper(II) complex, Cu^sup II^L, by N-bromosuccinimide (SBr) in weakly aqueous acidic solutions was studied under pseudo-first-order conditions. Plots of ln(A ^sub â z^Â â 'Â A ^sub t^) versus time where A ^sub t^ and A ^sub â z^ are absorbance values of the Cu(III) product at time t and infinity, respectively, showed marked deviations from linearity. The curves showed an acceleration of reaction rate consistent with an autocatalytic behavior. In the presence of Hg(II) ions, plots of ln(A ^sub â z^Â â 'Â A ^sub t^) versus time are linear up to >85Â % of reaction. The value of the observed rate constant, k ^sub obs^, increases with decreasing pH. At constant reaction conditions, the dependence of the observed rate constants, k ^sub obs^, is described by Eq. (1)...The dependence of both k ^sub o^ and k ^sub 1^ on [SBr] is not linear. The mechanism of the title reaction is consistent with an inner sphere mechanism in which a pre-equilibrium step precedes the electron transfer step. The overall rate law is represented by Eq. (2) where [Cu^sup II^L]^sub t^ and K ^sub 1^ represent the total copper(II) complex concentration and the pre-equilibrium formation constant, respectively...[PUBLICATION ABSTRACT]

• Publisher: Springer Nature B.V