Kinetic and Mechanistic Study of the Oxidation of D-Galactose by Tetraethylammonium Chlorochromate in Aqueous Acetic Acid Medium

Abstract

In an attempt to develop new oxochromium(VI) reagents for effective and selective oxidation of organic substrates under mild conditions, the oxidation kinetics of D-galactose with tetraethylammonium chlorochromate (C₂H₅)₄NcrO₃Cl has been studied in aqueous acetic acid medium 50% (v/v) in the presence of perchloric acid at constant ionic strength. The reaction, under pseudo-first order condition, is first order with respect to both the [oxidant] and the [substrate]. The reaction is markedly catalyzed by [H⁺] and the effect of [NaClO₄] is negligible. Increasing the dielectric constant of medium decreases the reaction rate. A 1 : 1 stoichiometry is observed and the reaction did not induce the polymerization of acrylonitrile. The reaction has been carried out at different temperatures and the various activation parameters have been computed.