Kinetic Study of Silver-Catalysed Oxidation of α-Hydroxy Monocarboxylic Acids - dl-Atrolactic, Isobutyric, Mandelic and Benzilic Acid by Potassium Peroxydisulphate

D. S. College, Aligarh Hindu College, Moradabad Manuscript received 23 April 1979, revised 11 May 1981, accepted 22 July 1981 The oxidatloo of dl-atrolactlc, benzillc, mandelic and α - hydroxy isobutyric acids by peroxydisalphate in the preseace of Ag(l) shows first order dependence on [S2\(O^2_{3}\)] and [Ag(l)] and zero order dependence on [acid]. The first order specific reaction rate in case of all the acids decreases with an increase In K2S2O8 conceotration and increases with an increase in Ag(l) concentration. Allyl acetate and H+ ion exert an inhibitory effect on the oxidation rate of the acids. The salt effect is negative and of exponential type. Various metal ions inhibit the reaction rate in the order K+ > Na+ > Zn+2 > Mg+2 > AI+2. The stoichiometry In the reaction between the hydroxy acids and S2\(O^2_{3}\) ion is 1:1. Various energy parameters have been calculated for all acids. The result have been explained by suitable reaction mechanism that the oxidation of α - hydroxy acids proceeds through C-C bond fission which results In decarboxylation giving rise to a carbogyl compound