The Mechanisms of Racemization of the 2,2'-Bipyridinebis-(1,10-phenanthroline) nickel(II) Ion and the 1,10-Phenanthrolinebis-(2,2'-bipyridine)-nickel(II) Ion

Abstract

The rates of racemization of the 1,10-phenanthrolinebis-(2,2'-bipyridine)nickel(II) ion and the 2,2'-bipyridinebis-(1,10-phenanthroline)nickel(II) ion have been measured in neutral, acid, and basic solutions as well as in organic solvents. Comparison of the rates in acid solution with the corresponding rates of dissociation has shown that racemization takes place by means of an intermolecular mechanism with the loss of one bipyridine ligand. Increased racemization rates in the presence of acids, bases, and specific ions such as NO₂^-;, Cl^-, Br^- have been accounted for by the same mechanism.