Structural and mechanistic studies of co-ordination compounds. Part 21. Base hydrolysis of some trans-tetra-aminedichlororuthenium(III) cations

Abstract

The base-hydrolysis kinetics for the release of the first co-ordinated chloride from trans-[RuCl₂L]⁺[L =(NH₃)₄, (en)₂(en = ethylenediamine), 3,7diazanonane-1,9- diamine, or 1,4,8,11 -tetra-azacyclotetradecane] have been studied. All the complexes react by second-order kinetics with complete retention of configuration. The observed increase in reactivity with increased chelation has been explained in terms of the nephelauxetic effect of the amine ligands on the central metal ion. An S_N1 (CB) mechanism in which a σ-trans effect of the amido-group operates has been proposed to explain the reactions.