Diethyl Sulfide Oxidation with Sodium Peroxoborate in Water–Acetonitrile System. Kinetics and Mechanism

Abstract

In aqueous solutions of acetonitrile (1 vol%), the rate of oxidation of diethyl sulfide with sodium peroxoborate, Na2[B2(O2)2(OH)4]∙6H2O, in the pH range of 8.5–11 is significantly higher than the oxidation rate in water and exceeds the rate of reaction of Et2S with hydrogen peroxide in the H2O–MeCN system. The reaction order with respect to the substrate, which is close to zero, suggests that the limiting stage of the process is the reaction of peroxoborate anions with MeCN, leading to the formation of active boron peroxyimidates, which then react in a rapid stage with Et2S.