Kinetic and mechanistic study of the oxidative deamination and decarboxylation of L-valine by alkaline permanganate

The kinetics of the oxidation of L-valine, (L-Val) by permanganate in aqueo us alkaline medium at a constant ionic strength of 0.50 mol . dm(-3) was st udied spectrophotometrically. The reaction is of first order in [permangana te ion] and of fractional order in both [L-Val] and [alkali]. Addition of p roducts has no significant effect on the reaction rate. However, increasing ionic strength and decreasing dielectric constant of the medium increase t he rate. The oxidation process in alkaline medium has been shown to proceed via two paths, one involving the interaction of L-valine with permanganate ion in a slow step to yield the products, and the other path the interacti on of alkali with permanganate ion to give manganate. Some reaction constan ts involved in the mechanism were determined; calculated and observed rate constants agree excellently. The activation parameters were computed with r espect to the slow step of the mechanism.