Micellar-Assisted Oxidation of D-Glucose by Imidazolium Fluorochromate in a 50% (v/v) Aqueous Acetic Acid Medium: A Kinetic and Mechanistic Approach

Abstract

This work examined the impact of sodium dodecyl sulfate (SDS) surfactant on the oxidation kinetics of D-glucose employing imidazolium fluorochromate (IFC) as the oxidant. The experiments were conducted under pseudo-first-order conditions at 30 °C, with D-glucose in a significantly higher concentration than IFC. The solvent medium used was 50% (v/v) aqueous acetic acid. The reaction demonstrated a first-order dependence on [IFC] and [HClO₄]. The order for [D-glucose] oxidation kinetics was slightly less than one. Perchloric acid acted as a catalyst in this process. The addition of acrylonitrile had no effect on rate constants (k_obs). k_obs decreased with an increase in the concentration of Mn(II) ions. An increase in the dielectric constant of the medium had an inverse effect on k_obs. The initial increase in [SDS] led to a corresponding rise in k_obs, though a saturation in k_obs was observed for elevated [SDS]. The Menger-Portnoy and Piszkiewicz models were used to quantitatively assess the experimental results. The binding constant (K_p), cooperativity index (n), and various thermodynamic parameters in the presence of SDS were calculated. Infrared and mass spectroscopy were used to ascertain D-gluconolactone as the primary product of the reaction. Based on these findings, a reaction scheme has been suggested.