Russian Journal of Organic Chemistry, Vol. 38, No. 5, 2002, p. 753. Translated from Zhurnal Organicheskoi Khimii, Vol. 38, No. 5, 2002, p. 789.
Original Russian Text Copyright
2002 by Svetlakov, Nikitin, Orekhova.
SHORT
COMMUNICATIONS
Oxidation of Diethylene Glycol with Nitric Acid
N. V. Svetlakov, V. G. Nikitin, and A. O. Orekhova
Kazan State Technological University, ul. Karla Marksa 68, Kazan, 420015 Tatarstan, Russia
Received July 24, 2001
It is known that nitric acid is capable of splitting
ether bonds to give carboxy groups [1] and that
heat evolution was over ( 2 h), the mixture was kept
for 12 14 h at 20 C, and the product was filtered off
and dried at 60 C. Yield 18.6 g (85%). mp 148 C
aliphatic alcohols react with HNO to afford alkyl
3
1
nitrates [2]. Diethylene glycol can react with nitric
acid at both the ether bond and the hydroxy groups.
We performed oxidation of diethylene glycol with
(from water) [3]. IR spectrum, , cm : 1720 (C O),
1
2400 3200 (COOH). H NMR spectrum, , ppm:
4.2 s (4H, CH ), 7.0 br.s (2H, OH).
2
8
5% nitric acid at 25 30 C. The reaction was exo-
Reproducible results were obtained with enlarged
amounts of the reactants (by several times). In some
cases, a seed should be added to initiate crystalliza-
tion. In order to increase the yield of the product, it
is advisable to cool the reaction mixture below 0 C.
thermic and was accompanied by evolution of nitro-
gen oxides. In 1.5 2 h after mixing of the reactants,
colorless crystals began to separate. The product was
identified as diglycolic acid.
We used diethylene glycol A containing 99.5% of
the main substance and 97% nitric acid of technical
grade which was diluted with water to a required
concentration.
The H NMR spectrum was recorded on a Tesla-
497 spectrometer (100 MHz) at room temperature
Presumably, the reaction involves intermediate
formation of diethylene glycol dinitrate which is
unstable at elevated temperature [2]. The presence of
1
O NO groups reduces the nucleophilicity of the ether
using acetone-d as solvent and HMDS as internal
2
6
bond, so that the latter remains unchanged under the
given conditions. This reaction provides a convenient
procedure for preparation of diglycolic acid: The
procedure is fairly simple and it utilizes accessible
starting compounds. The known methods for prepara-
tion of diglycolic acid are based on dehydration of
glycolic acid above 200 C or transformations of halo-
acetic acids [3].
reference. The IR spectrum was measured on a UR-20
instrument.
REFERENCES
1. Freidlin, G.N., Alifaticheskie dikarbonovye kisloty
(Aliphatic Dicarboxylic Acids), Moscow: Khimiya,
1978, pp. 50 65.
Diethylene glycol, 15.7 g (0.15 mol), was added
with stirring at 25 30 C to 56.7 g of 85% nitric acid
2. Orlova, E.Yu., Khimiya i tekhnologiya brizantnykh
vzryvchatykh veshchestv (Chemistry and Technology
of High Explosives), Moscow: Oborongiz, 1960,
pp. 301, 329.
(
0.9 mol of HNO ). The temperature was maintained
3
by cooling with cold water. The reaction was accom-
panied by evolution of nitrogen oxides. When the
entire amount of diethylene glycol was added and
3. Beilsteins Handbuch der organischen Chemie, H,
vol. 3, p. 234.
1
070-4280/02/3805-0753$27.00 2002 MAIK Nauka/Interperiodica