Hydrolysis of phenyl trifluoroacetate in mixed surfactant systems

Abstract

The rate of spontaneous hydrolysis of phenyl trifluoroacetate (1) was measured in pure and mixed fluorocarbon/hydrocarbon surfactant systems. The reaction is inhibited by the surfactants when their concentrations are higher than the critical micelle concentration. The same behavior is observed in mixtures of surfactants. The kinetic analysis according to the pseudophase separation model indicates that the contribution of the micelle‐associated substrate hydrolysis rate to the overall observed rate constant is negligible. In that condition, the substrate is less available for water. The differences in inhibition observed for the hydrolysis reaction of 1 in the studied systems are due to the contribution of several effects: differences in polarity of the interfaces, protection of the substrate (reactive center) inside the micelles, and stabilization of the transition state. The association constants of 1 with the surfactants and their mixtures were also determined. Copyright © 2016 John Wiley & Sons, Ltd.