Kinetics of the solvolysis of the trans‐dichlorobis(1,2‐diaminoethane)‐cobalt(III) Ion in water + urea mixtures

Abstract

AbstractFollowing the kinetic investigation of the solvolysis of a range of cobalt(III) complexes in mixtures of water + cosolvent wherethe cosolvent enhances the solvent structure and decreases the dielectric constant, kinetic data are now reported for such a solvolysis in water + urea where urea acts as a structure breaker and enhances the dielectric constant. A plot of log (rate constant) against reciprocal of the dielectric constant shows that differential effects of changes in solvent structure occur between the initial and the transition states and, as in theinvestigations using structure‐enhancing cosolvents, the principal effect of change in solvent structure on the cobalt(III) cation occurs on the penta‐coordinated ion in the transition state.