Kinetics of organic reactions in micelles

Abstract

Those features of micellar organization and structure most pertinent to the understanding of micellar catalysis of organic reactions are briefly reviewed. Of crucial importance are the properties of the micelle-water interface: Marked hydrophobicity and hydrophilicity as manifested in binding of both organic molecules and ions to the micellar surface; a surface dielectric constant near 35; the high concentration of charged groups at the micellar surface; a water activity near unity; and the presence of functional groups. Those factors contributing to micellar catalysis are reviewed. for nonfunctional micelles, effects are either the consequence of the nature of the reaction medium (activity coefficient effects), the concentration of reactants (entropy effects) or both. Pertinent examples are cited including decarboxylations, phosphate ester hydrolyses, fading of dyes, and addition of cyanide ion to pyridinium ions. Finally, theoretical treatments of micellar catalysis are briefly reviewed, pointing out that equations derived by Berezin and by Romsted account satisfactorily for many features of micelle catalysis. © IUPAC