The effect of N-tetradecyl-N,N-dimethylamine oxide micelles on the kinetics of the electron transfer reaction of Ce(IV) with substituted malonic acids

The kinetics of the oxidation of malonic acid and (its substituted compounds, methyl-, ethyl-, butylandbenzyl-malonic acid) by ceric ions has been studied at 20.0 ◦C in the absence and the presence ofthe surfactant N-tetradecyl-N,N-dimethylamine oxide (C14DMAO). The addition of increasing amountsof C14DMAO influences the rate of the redox process to an extent that significantly depends on thehydrophobicity of the reducing species. The reactivity data together with the estimated binding constantsand the standard transfer free energies of the malonic acids from water to the micelles suggest that themalonic acid is confined to the aqueous pseudo-phase while for the other solutes the binding occurs inthe palisade layer of micelles.