Kinetics and Mechanism of Atenolol Oxidation in Alkaline Permanganate Medium

Abstract

The kinetic and mechanistic study of the oxidation of the emerging pharmaceutical
contaminant atenolol by alkaline permanganate in a potassium hydroxide medium was
conducted spectrophotometrically under pseudo-first-order conditions, utilizing an excess of
permanganate. IR spectroscopy was used to find the oxidation product, which proved that the
corresponding oxidized derivative of atenolol had formed. The reaction's stoichiometry was 1:2.
which means that one mole of atenolol reacts with two moles of Mn(VII). The reaction exhibited
pseudo-first-order kinetics concerning permanganate and demonstrated fractional order
dependence on both [atenolol] and [OH⁻], with each value being less than one. The oxidation
happens when an intermediate complex forms between atenolol and the reactive alkaline
permanganate species. This complex then breaks down to make the final products. The reaction
rate went down when the dielectric constant of the medium went down. This suggests that
charged species are involved in the step that sets the rate. We also looked at how ionic strength
and the products that were added at first changed things. Kinetic studies conducted at various
temperatures facilitated the assessment of activation and thermodynamic parameters.