ISSN 1070-4272, Russian Journal of Applied Chemistry, 2008, Vol. 81, No. 2, pp. 320!322. + Pleiades Publishing, Ltd., 2008.
Original Russian Text + L.S. Postnikov, I.V. Korovina, A.D. Kagarlitskii, L.A. Krichevskii, 2008, published in Zhurnal Prikladnoi Khimii, 2008,
Vol. 81, No. 2, pp. 332!334.
Oxidative Ammonolysis of 2-Methylquinoxaline
on Vanadium!Titanium Oxide Catalyst
L. S. Postnikov, I. V. Korovina, A. D. Kagarlitskii, and L. A. Krichevskii
Fitokhimiya Research and Production Center, Joint-Stock Company, Karaganda, Kazakhstan
Received July 21, 2007
Abstract-The behavior of 2-methylquinoxaline in the course of oxidative ammonolysis on V3Ti oxide
catalyst in a wide range of conditions was studied, and this reaction was examined as a route to 2-quinoxaline-
Quinoxalines, or benzopyrazines, form an import-
ant group of heterocycles. They exhibit a broad spec-
trum of biological activity, including antibacterial,
antitumor, fungicidal, and antiviral activity .
Interest in oxidative transformations of quinox-
alines is due to the fact that the oxidation products
can be used as starting compounds for preparing vari-
ous drugs by more efficient procedures than multistep
methods of classical organic chemistry.
As investigation object we chose readily accessible
2-methylquinoxaline synthesized by condensation of
o-phenylenediamine with a-isonitrosoacetone :
The majority of studies devoted to oxidation of qui-
noxalines are concerned with transformations of sub-
stituents at both benzene and pyrazine rings. Some
papers deal with various procedures for preparing qui-
noxaline N-oxides showing pronounced biological
activity. There are also papers reporting on oxidation
of quinoxalines with the aim to obtain pyrazine deriv-
atives, in particular, pyrazinecarboxylic acid [3, 4].
It seemed interesting to perform oxidative ammo-
nolysis of 2-methylquinoxaline as a possible route to
2-quinoxalinecarbonitrile, a synthetic precursor of new
compounds of the quinoxaline series. As catalyst we
used the system V
= 1 : 8 . The start-
ing compound was fed as a solution in aqueous am-
The process parameters were as follows: tempera-
ture 3203 460oC; amounts of ammonia and water 2.53
12.5 and 353 48 mol per mole of 2-methylquinoxaline,
respectively; contact time 0.332.0 s.
The reaction products were trapped in an airlift
absorber filled with chloroform. The products were
separated by column chromatography on silica gel,
eluent hexane3chloroform, 6 : 1.
Gas-chromatographic and spectral studies showed
that the catalyzates from oxidative ammonolysis of
2-methylquinoxaline contained unchanged starting
compound, 2-quinoxalinocarbonitrile, quinoxaline,
Fig. 1. Yield Y of products of oxidative ammonolysis
of 2-methylquinoxaline in the presence of the catalyst
vs. temperature T. Amounts of NH
O 12.5 and 35 mol per mole of 2-methylquinoxaline,
respectively; contact time 0.7 s. (1) 2-Methylquinoxaline,
(2) quinoxaline, and (3) 2-quinoxalinecarbonitrile; the same
for Figs. 2 and 3.