Kinetics and mechanism of oxidation of aliphatic alcohols by [bis(trifluoroacetoxy)iodo]benzene

Abstract

The oxidation of some aliphatic alcohols by [bis(trifluoro-acetoxy)iodo]benzene (TFAIB) in aqueous acetic acid solution leads to the formation of the corresponding carbonyl compounds. The reaction is first order in TFAIB and a Michaelis-Menten kinetics is obtained with respect to the alcohols. The reaction shows a first order dependence on hydrogen ions. The oxidation of [1,1–²H₂]ethanol and [2-²H]propan-2-ol exhibits the presence of a substantial primary kinetic isotope effect at 298 K (kH/kD = 3.64 and 3.89 respectively). The rate of disproportionation of the intermediate is susceptible to both polar and steric effects of the substituents. A suitable mechanism has also been proposed.