Oxidation of some aldopentoses by chloramine-B in alkaline medium: a kinetic and mechanistic study

Article abstract of DOI:10.1016/0008-6215(90)84035-S

The oxidation kinetics of D-xylose, D-ribose, and L-arabinose by chloramine-B (CAB) in alkaline medium at 35 deg C obey the rate law, rate = ->.Based on the results, a mechanism is suggested involving the anion of the β anomer of the pentose.The addition of reaction products, benzenesulphonamide and NaCl, had no effect on the rate of reaction whereas increase in the ionic strength and dielectric constant of the medium increased the rate.Proton-inventory studies were made in H2O-D2O mixtures.The rate of oxidation of pentoses follows the order: D-xylose > D-ribose > L-arabinose.Kinetic and thermodynamic parameters for the reaction were computed from the Arrhenius plots.The isokinetic temperature β = 416 K, which is much above the experimental temperature, suggests enthalpy-controlled reactions.