OXIDATIVE ADDITION REACTIONS OF d8 COMPLEXES. I. CHLORINE OXIDATION OF TETRACHOLOROPALLADATE (II)

Abstract

The reaction of Na₂PdCl₄ with chlorine in aqueous acid solution proceeds in two stages: oxidation of the complex to a Pd(IV) species followed by a slower substitution reaction. The oxidation reaction is first order in complex and first order in chlorine. At high chloride concentration, a six-coordinate palladium(II) intermediate is formed, which is oxidised via an outer-sphere type mechanism. Oxidation of the chloroaquopalladium(II) species present at low chloride concentration occurs via a different mechanism, probably involving coordination of the oxidant in a ‘quasiinner-sphere’ mechanism.