Metal ligand reactions micellar systems

The kinetics and mechanism of a range of slow metal-ligand substitution processes have been investigated, and a generalized theory was proposed that was very similar to the Berezin model for the interpretation of micelle kinetics in aqueous solutionsJ Ligands of different hydrophobicity were studied in terms of their reaction with Ni +(aq), and it was found that for p3rridine-2-azo-p-phenol (PAP), the rate constants kf for reaction in SDS micellar solution and water/Na-AOT/heptane systems were comparable, as shown in Table 10.2. kf is expressed as a first-order rate constant in the microemulsion.)... 

However, there is an important difference between these two systems in the ligand-metal ion ratio in complexation. Namely, micellar reactions require a more generalized reaction Scheme 3, where the molarity of ligand n is either 1 or 2 depending upon the structure of the ligands. This scheme gives rates Eq. 2-4 for n = 1 and Eq. 3, 5, 6 for n = 2. The results of the kinetic analysis are shown in Table 3. 

The kinetics and mechanisms of ligand-substitution reactions involving labile metal ions in aqueous solution are now well understood (1). It is therefore of interest to investigate how such reactions are affected when the reaction medium is changed either by addition of charged micelles to an aqueous solution or by dispersing the reactants in an inverse-micellar (water-in-oil microemulsion) system. 

---