Electron-Transfer Reactions in Non-Aqueous Media. VI. A Temperature-Dependence Study of the Reduction of cis-[CoCl₂(en)₂]⁺ by Iron(II) in Me₂SO

Abstract

The kinetics of the reduction of cis-[CoCl₂(en)₂] ± (en = ethylenediamine) by iron(II) in Me₂SO have been studied at four temperatures. The rate law has the form

d[Co^III]/dt = kK [CO^III][Fe^II]/(1+K[F^II])

The pseudo-first-order rate constants determined at high [Fe^ll] have been resolved into k and K, and their independent temperature dependence has been studied. The results are totally consistent with an inner-sphere electron-transfer process in which the precursor complex contains a double bridge using both the cis-chloro ligands and in which the iron atom is octahedrally coordinated.