OXIDATION OF VANILLIN BY IODATE IN AQUEOUS ACETIC ACID MEDIUM: A KINETIC AND MECHANISTIC STUDY

The kinetics and mechanism of the oxidation of vanillin by iodate in aqueous acetic acid medium is studied. The reaction exhibits first order in [Iodate], fractional order in [vanillin] and [acid]. Variation of ionic strength had no effect on the reaction rate. Increase in the reaction rate by a decrease in the dielectric constant of the medium is observed. The reaction was studied at four different temperatures and the related activation and thermodynamic parameters were calculated. The product of oxidation was confirmed as vanillic acid by spectral analysis. Based on the results a plausible mechanism has been proposed and the appropriate rate law has been derived.