Kinetics and Mechanism of Oxidation of Alcohols by Ceric Ammonium Nitrate

Department of Chemistry, University of Jodhpur, Jodhpur-342 001

Manuscript received 24 May 1984, revised 1 March 1985, accepted 3 June 1985

The main product of the oxidation or secondary alcohol by ceric ammonium nitrate is the corresponding ketone. The reaction Is of first-order with respect to the oxidant but exhibit a Michaelis-Menten type kinetics with respect to the alcohol. The formation constants of the alcohol Ce^IV complex and Its thermodynamic parameters have been calculated. The rate of decomposition of the complex and the activation parameters have also been evaluated. The rates of decomposition of the complex correlate with Taft's σ^* values with a low negative reaction constant. The oxidation induced polymerisation of acrylonitrile. The retardation of rate with increasing acidity has been explained on the formation or kinetically Inactive protonated alcohol. The protonated constants for the various alcohol have been calculated. The presence of a small primary kinetic isotope effect k_H /k_D -1.3, confirms that the rate-determining step Involves a C—H bond rupture in a non-symmetrical transition state.