The study of the Kinetics of D-mannose Oxidation with Imidazolium Fluorochromate in Aqueous Acetic Acid Medium through Spectrophotometric Analysis

Kinetics and mechanism of oxidation of D-mannose with imidazolium fluorochromate (IFC) have been studied in a 1:1 volume ratio aqueous acetic acid medium. The oxidation study revealed first- order relationship on concentration of D-mannose, imidazolium fluorochromate, and perchloric acid. The reaction rates were enhanced by perchloric acid, and maintained a 1:1 stoichiometric ratio. A constant ionic strength was ensured across the reaction mixture. Further, variations in ionic strength values reflected shallow effect on oxidation rates. The reaction rates decreased in the solvent of high dielectric constant (delta). The observed results were in agreement with the Amis and Kirkwood plots, namely (logK(1) vs (1/delta) and (delta-1/2 delta+1)). Polymerization of acrylonitrile was absent in the reaction. The oxidation rates were recorded across the range of temperatures, and several thermodynamic variables were computed. The products of the oxidation reaction were arabinose and formic acid. A reaction mechanism supported by observed findings was suggested.