OXIDATION OF 6-METHYL-2,4-DIOXYPYRIMIDINE
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electrophilic attack on the 5-position of pyrimidine
ring followed by the formation of 6-methylene
derivative and its subsequent intramolecular oxidation
to form Se and orotic aldehyde.
hydrochloric acid and boiled for 15 min. After the
addition of powdered charcoal (3 g) the mixture was
boiled for 15 min. The solution was separated from the
adsorbent by filtration. After distilling off the water in
a 10–15 mm Hg vacuum to a volume of 70–80 ml, the
residue was cooled. The precipitated orotic aldehyde
was filtered off and washed on a filter with 20 ml of
water, 20 ml of ethanol and 100 ml of diethyl
ether. Orotic aldehyde was purified by sublimation in
vacuum (10 Hg mm). Yield 8 g (45.5%), mp 273–275°C
(decomp.), which corresponds to the published data [1,
5, 6]. In addition, after cooling the mother liquor (after
washing with water and ethyl alcohol) 3 g of orotic
aldehyde was obtained with the same parameters. The
total yield of orotic aldehyde was 11 g (62.5%).
One can also assume that the difference between
the oxidation of the methyl group in compound I with
acid IV consists in the fact that along with the mixed
anhydride of selenious and acetic acid, in the reaction
also take part selenious acid anhydride formed by the
intermolecular dehydration. In addition, the released
water molecules in the reaction of selenious acid with
acetic acid is always in the reaction sphere due to the
dipole–dipole interaction with an selenium atom and
associative interactions with a molecule of orotic
aldehyde, which favors the final stage in the direction
of the end reaction products.
REFERENCES
EXPERIMENTAL
1. Mikhailopulo, I.A., Gunar, V.I., and Zav’yalov, S.I., Izv.
Akad. Nauk SSSR, Ser. Khim., 1967, p. 1388.
2. Zee-Cheng Kwang-Yuen and Cheng, C.C., J. Hetero-
cyclic Chem., 1967, vol. 4, p. 163.
3. Schmidt, M.W., Baldridge, K.K., Boatz, J.A., Elbert, S.T.,
Gordon, M.S., Jensen, J.H., Koseki, S., Matsunaga, N.,
Nguyen, K.A., Su, S.J., Windus, T.L., Dupuis, M., and
Montgomery, J.A., J. Comput. Chem., 1993, vol. 14,
p. 1347.
1H NMR spectra were recorded on a Varian
Mercury instrument (300 MHz) in CCl4 or CDCl3
relative to internal HMDS. The IR spectra were taken
on a Specord-M82 instrument (liquid film).
Synthesis of orotic aldehyde (III). A three-necked
400 ml reactor equipped with a stirrer, a thermometer
and a reflux water-cooled condenser was charged with
15.9 g (0.13 mol) of 6-methyl-2,4-dioxypyrimidine I,
and then was added 250 ml of glacial acetic acid. The
mixture was kept at 50–60°C until the complete
dissolution. Then 9.15 g of selenious acid was dosed. The
resulting mixture was refluxed for 5 h with stirring.
4. Nakamura, F. and Kuwajima, I., J. Am. Chem. Soc.,
1977, vol. 99, p. 961.
5. Shul’man, R.B. and Rakhimov, A.I., Abstract of Papers,
37 Nauchnaya konferentsiya “Sintez, farmakologiya i
klinicheskie aspekty novykh psikhotropnykh
i
serdechno-sosudistykh veshchestv” (37 Sci. Conf.
“Synthesis, Pharmacology and Chemical Aspects of
New Psychotropic and Cardiovascular Drugs”),
Volgograd, 2000, p. 15.
The precipitated gray mass of selenium (recovered
as compound IV [4]) was filtered off on a Schott’s
filter and washed thoroughly with hot acetic acid.
Acetic acid was distilled off from the filtrate under
vacuum (10–15 Hg mm). The resulting residue was
dissolved in 300 ml of water acidified with 0.4 ml of
6. Rakhimov, A.I., Kryukov, I.E., Shul’man, R.B., and
Sinel’nikov, P.Yu., Izv. Volgograd. Gos. Tekh. Univ.,
Ser. Khim. i Tekhnol. Elementoorg. Monomerov i
Polimernykh Materialov, 2000, no. 2, p. 170.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 11 2011