Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 7, pp. 1243−1247.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
E.V. Potapenko, P.Yu. Andreev, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 7, pp. 1137−1141.
AND INDUSTRIAL ORGANIC CHEMISTRY
Oxidation of Benzyl Alcohol and Benzaldehyde
with Ozone in Acetic Acid
E. V. Potapenko and P. Yu. Andreev
Institute for Chemical Technology, Dal’ Eastern-Ukrainian National University, Rubezhnoe,
Lugansk oblast, Ukraine
Received September 3, 2009
Abstract—Ozonation of benzyl alcohol and benzaldehyde in acetic acid was studied. A method for ozonation
of these compounds is suggested.
Liquid-phase oxidation of methylbenzenes with ozone
has been rather long considered a promising way to obtain
aromatic carboxylic acids . In the course of ozonation,
the primary comparatively stable products of oxidation
of the methyl group are aromatic alcohols and aldehydes.
Despite that their concentration in the system is rather
low, these substances undoubtedly play an important role
in deep conversion stages of methylbenzenes.
Apparently, to extend the concepts of processes
for oxidation of methylbenzenes, it is also necessary
to understand the fundamental kinetic aspects and
mechanism of the reaction of ozone with aromatic
alcohols and aldehydes.
In this context, it is of interest to study the
fundamental aspects of ozonation of benzyl alcohol
and benzaldehyde in acetic acid under the conditions
characteristic of oxidation of methylbenzenes.
The interaction of benzyl alcohol with ozone in
acetic acid is accompanied by preferential oxidation of
the oxymethyl group (Fig. 1). Benzoic acid accumulates
as the main product (83.7%), with the amount of
ozonides not exceeding 15.2%. Benzaldehyde is formed
in parallel with benzoic acid in minor amounts.
Introduction of cobalt(II) acetate into the oxidizing
system makes it possible to raise both the yield of
benzoic acid (95.4%) and the consumption rate of the
alcohol (Fig. 1). It is noteworthy that benzoic acid is
formed in the presence of the catalyst after a sufﬁ cient
amount of benzaldehyde accumulates in the reaction
mass. This is indicative of the successive nature of their
formation. Already in the ﬁ rst minutes of ozonation,
cobalt becomes trivalent and after that its concentration
In contrast to benzyl alcohol, the main reaction
pathway in ozonation of benzaldehyde is the destruction
of the aromatic ring (52.3%), with the yield of benzoic
Fig. 1. Kinetic curves of (1, 1') consumption of benzyl alcohol
and accumulation of (2, 2') benzoic acid, (3, 3') benzaldehyde,
and (4) ozonides in ozonation (1–4) in the absence of a catalyst
and (1'–3') in the presence of cobalt(II) acetate in acetic acid at
OH] = 0.069 M, [O
] = 4 × 10
0.08 M. (c) Concentration and (τ) reaction duration; the same
for Fig. 2.
c × 10