Kinetics and mechanism of oxidation of alcohols by butyltriphenylphosphonium dichromate

Abstract

2039-2043Butyltriphenylphosphonium dichromate (BTPPD) oxidizes aliphatic alcohols to the corresponding carbonyl compounds. The reaction is first order in BTPPD. The reaction exhibits a second order dependence each on the alcohol and hydrogen ions. The oxidation of deuteriated ethanol and 2-propanol indicates the presence of a substantial primary kinetic isotope effect. The reaction has been studied in nineteen organic solvents and the solvent effect was analyzed using multiparametric equations. It is observed that the cation-solvating power plays a major role in the reaction. The rate of oxidation shows excellent correlation with the polar and steric substituent constants. Suitable mechanisms have been proposed