Mechanistic Study of Oxidation of Primary Alcohols by Quinolinium Fluorochromate using Micro-amount of Ghloro-complex of Ir(III) as a Homogeneous Catalyst in Acidic Medium

摘要

The mechanistic study of iridium(III) catalyzed oxidation of n-hexanol and n-heptanol (primary alcohols) has been studied by quinolinium fluorochromate (QFC) in aqueous perchloric acid medium at 308 K. The reaction followed zero order kinetics with respect to [primary alcohols]. First-order kinetics with respect to [QFC] and [Ir(III)] were observed for the oxidation of primary alcohols. The rate of reaction decreased with increasing [Cl~-]. The variation of [H~+] and ionic strength of the medium had no significant effect on the rate of the reaction. The values of rate constants observed at four different temperatures were utilized to calculate the activation parameters. The reaction between QFC and primary alcohols, in acidic medium, exhibits 1:1 stoichiometry. A plausible mechanism conforming to the kinetic results has been proposed.