Oxidation of α,β-Unsaturated Alcohols by Nicotinium Dichromate: A Kinetic Study

Abstract

Kinetics of oxidation of  α, β-unsaturated alcohols by nicotinium
dichromate (NDC), have been studied in 50% acetic acid-water
medium. The reaction is first order each in the concentration of
oxidant and substrate  Increase in acidity increases the rate of  the
reaction. Increase in ionic strength has appreciable effect on the
reaction rate. The rate of the reaction decreases with increase in the
dielectric constant of the medium. The reaction does not induce the
polymerization of acrylonitrile. The retardation of the rate by the
addition of Mn²⁺ ions confirms that a two electron transfer process
is involved in the reaction. The reaction rates have been determined
at different temperatures and the activation parameters calculated
and a suitable mechanism has been proposed. The order of reactivity
is allyl alcohol < crotyl alcohol < cinnamyl alcohol.