Kinetics of the Acid-Base Catalyzed Hydration of 1,3-Dichloroacetone in the Presence of Triton X-100 Reversed Micelles in Carbon Tetrachloride

Article abstract of DOI:10.1021/jo00200a044

The kinetics of the reversible hydration of 1,3-dichloroacetone catalyzed by hydrochloric acid or by imidazole buffer solubilized by the reversed micelles of the nonionic surfactant Triton X-100 in carbon tetrachloride have been studied spectrophotometrically.Rate and equilibrium constants, kinetic isotope effects, and activation parameters have been determined as a function of the / molar ratio.The rate constants were found to be similar to those obtained in the presence of the reversed micelles of the anionic surfactant Aerosol-OT but higher (by factors from 4 to 327) than those for the same reaction in aqueous dioxane.On the basis of the obtained data, transition-state structures for the acid- or base-catalyzed reactions are suggested that clearly show the catalytic role (acid-base) played by the surfactant.The observed rate enhancement is attributed to this participation of the detergent which entails differences between the structures of the transition states for the micelle-mediated reactions and those in aqueous dioxane.