Croatica Chemica Acta, Vol. 84 No. 1, 2011.
Original scientific paper
https://doi.org/10.5562/cca1694
Kinetics and Mechanism of the Oxidation of Aliphatic Aldehydes by Benzimidazolium Dichromate
Pravesh Kumar
; Department of Chemistry, J N V University, Jodhpur 342 001, India
Dinesh Panday
; Department of Chemistry, J N V University, Jodhpur 342 001, India
Seema Kothari
; Department of Chemistry, J N V University, Jodhpur 342 001, India
Abstract
Kinetic and mechanistic studies of the oxidation of aliphatic aldehydes, (in organic non-aqueous
solvents), were discussed with an emphasis of correlation of structure and reactivity. The reactions were
of first order with respect to BIDC and hydrogen-ion. However, Michaelis-Menten type kinetics were observed
with respect to aldehyde. The deuterium isotope effect for the oxidation of acetaldehyde
(kH/kD = 6.36 at 298 K) indicated an α-C–H bond cleavage in the rate-determining step. Based on kinetic
data, analyses of the solvent effect and results of structure-reactivity correlation along with some nonkinetic
parameters suggested a mechanism involving rate-determining oxidative decomposition of a aldehyde-
BIDC complex via a cyclic transition state to give a carbocationic species through hydride-ion transfer
from the aldehyde to the oxidant. (doi: 10.5562/cca1694)
Keywords
kinetics; oxidation; aliphatic aldehydes; benzimidazolium dichromate; mechanism
Hrčak ID:
69694
URI
Publication date:
30.5.2011.
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