MEDIUM EFFECTS ON ALKALINE-HYDROLYSIS OF N-PHENYLBENZOHYDROXAMIC ACID

Kinetic studies of alkaline hydrolysis of N-phenylbenzohydroxamic acid have been investigated in aqueous dioxane, dimethyl sulphoxide, dimethyl formamide, acetone, acetonitrile, methanol and ethanol mixtures of varying compositions (0-80%, v/v) at different temperatures (55-75 degrees). The rate constant in all cases increases with increasing percentage of the solvent, which is attributed to solvation of the transition state, solute-solvent interactions and dielectric behaviour of the medium. The activation parameters have been evaluated and discussed in terms of solvation effect.