1070-4272/03/7602-0234 $25.00 C 2003 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 76, No. 2, 2003, pp. 234!237. Translated from Zhurnal Prikladnoi Khimii, Vol. 76, No. 2, 2003,
Original Russian Text Copyright C 2003 by Bazhenov, Kas’yanova, Bokin, Kutepov, Khazipova, Travkin, Shchadneva, Khusnutdinov, Dzhemilev.
Hydrogenation and Skeleton Rearrangements of =-Pinene
on Heterogeneous Catalysts
Yu. P. Bazhenov, L. Z. Kas’yanova, A. I. Bokin, B. I. Kutepov, A. N. Khazipova,
E. A. Travkin, N. A. Shchadneva, R. I. Khusnutdinov, and U. M. Dzhemilev
Kauchuk Private Company, Sterlitamak, Bashkortostan, Russia
Institute of Petrochemistry and Catalysis of the Republic of Bashkortostan, Ufa Scientific Center,
Russian Academy of Sciences, Ufa, Bashkortostan, Russia
Received May 14, 2002
Abstract-Hydrogenation and isomerization of a-pinene on heterogeneous catalysts were studied, and con-
ditions were found for hydrogenation of pinene to cis-pinane on nickel catalysts and for its dehydrogenation
to p-cymene on decationized zeolite Y.
a-Pinene, which is a bicyclic monoterpenoid, is
an important product of wood chemical industry.
a-Pinene widely occurs in nature; it is present in
oils obtained from most of coniferous tree species and
is the major component of turpentine. Due to the pres-
ence of a double bond and a strained four-membered
ring, a-pinene readily undergoes various transforma-
tions, primarily hydrogenation and skeleton isomeri-
a-Pinene is widely used in industry, in particular,
in production of synthetic camphor, camphene, myr-
cene, fragrances (linalool, citronellol, geraniol, pino-
carveol, myrtenol, etc.), and paint-and-varnish materi-
The a-pinene hydrogenation product, pinane, is
also an important chemical: its autooxidation yields a
stable hydroperoxide used as initiator of low-tempera-
ture copolymerization of butadiene with styrene .
Pinane required for preparing the hydroperoxide is
usually synthesized by hydrogenation of a-pinene
with molecular hydrogen on metal-containing cata-
lysts . In particular, it has been suggested [5, 6]
to use supported Ru- and Pd-containing catalysts for
a-pinene hydrogenation. Hydrogenation of a-pinene
can also be performed on Ni-containing catalysts, but
under more severe conditions: p
> 1.0 MPa and
reaction time no less than 14320h.
Our goal was to find catalysts effecting hydrogena-
tion of a-pinene to pinane under mild conditions
< 0.6 MPa, T < 150oC). The major attention was
given to hydrogenation of a-pinene on Pd- and Ni-
containing catalysts for hydrogenation of other or-
ganic substances, commercially produced in Russia.
Experiments on a-pinene transformations were per-
formed in a 100-ml isothermal pressure reactor con-
taining a finely dispersed (0.0430.1 mm) catalyst;
the ideal mixing mode was ensured by vigorous shak-
ing. The amount of loaded a-pinene was 50 ml, and
the amount of the catalytic system relative to sub-
=1310 wt %. The temperature in the reactor,
, was varied from 20 to 150oC, and the hydrogen
, from 0.2 to 1.0 MPa. Also, hydrogena-
tion of a-pinene was studied in a tubular bubbling re-
actor charged with a pelletized catalyst (V
= 100 ml);
the process was performed in a flow of hydrogen, in
the batch mode with respect to a-pinene.
The IR spectra were recorded on a UR-20 spec-
trometer; samples were prepared as KBr pellets, mulls
in mineral oil, or neat liquids. The
spectra were recorded on a Jeol FXQ spectrometer (90
and 22.5 MHz, respectively) in CDCl
chemical shifts (d, ppm) are given relative to TMS.
The mass spectra (70 eV) were taken on a Finnigan
MAT-112S gas chromatograph3mass spectrometer.
A chromatographic analysis was performed with a
Chrom-5 chromatograph, column length 1.2 m, sta-
tionary phase 5% SE-30 on Chromaton N-AW-HMDS,
carrier gas helium.
The reaction was performed with sulfate a-pinene
purified by distillation (99.0 wt % purity). The reac-