MECHANISM OF OH- PROMOTED HYDROLYSIS OF ACETOHYDROXAMIC ACID

Rate coefficients have been measured for the alkaline hydrolysis of ac etohydroxamic acid [CH3(C = O)NHOH] in 10% (v/v) dioxane-water at 85 d egrees C. The enthalpies and entropies of activation have been evaluat ed. Solvent effects, kinetic solvent isotope effects, salt effects and rate-acidity function correlations have been employed to elucidate th e mechanism. The evidence is consistent with hydrolysis mechanism with a rate determining attack of hydroxide ion to the carbonyl group, fol lowed by rapid collapse of the tetrahedral intermediate io form produc ts.