Mechanistic Insights into the Oxidation of Aminophylline by Potassium Permanganate in Basic Medium: A Kinetic and Spectrophotometric Approach

Abstract

he kinetics of oxidation of Aminophylline by potassium permanganate in alkaline medium has
been studied spectrophotometrically at 25°C keeping ionic strength constant at 0.1 mole dm–3.
The stoichiometric ratio of permanganate to aminophylline in alkaline media was found to be 1:4.
The kinetic study of the reaction between Aminophylline and permanganate ion has shown that
the reaction obeys first order kinetics. It was observed that the reaction was sub-unit order
dependent on both Aminophylline and hydroxide ion [OH−]. Increasing ionic strength did not
have any significant effect on the rate of the reaction. The main products were identified by IR
spectral analysis. The ionic strength and the dielectric constant had no effect on the rate of
reaction. The introduction of some products did not affect the reaction rate significantly. The rate
equation for this oxidation reaction has been established. Reaction constants and mechanism have
been calculated. The activation parameters associated with rate determining step of the reaction
as well as the thermodynamic values of the equilibrium constants have been estimated and
discussed