Kinetic, Mechanistic and Spectral Investigations of Oxidation of Gabapentin (neurontin) by Diperiodatoargentate(III) in an Aqueous Alkaline Medium

Abstract

The kinetics of the oxidative degradation of gabapentin by diperiodatoargentate(III) in aqueous alkaline medium at constant ionic strength of 0.10 mol dm -3 was studied spectrophotometrically using a rapid kinetics accessory. The reaction is first order in [DPA] and has apparent less than unit order in both [gabapentin] and [alkali]. Addition of periodate has a retarding effect on the rate of reaction. The reaction rate increased with increase in ionic strength and decrease in solvent polarity of the medium. Main products were identified by IR, NMR and mass spectral studies. A mechanism involving the monoperiodatoargentate(III) as the reactive species of oxidant has been proposed. The reaction constants involved in the mechanism are evaluated. The activation parameters are computed with respect to the slow step of the proposed mechanism.