Chemistry of Heterocyclic Compounds, Vol. 42, No. 7, 2006
SYNTHESIS OF 5-NITRO-1,2,3,4-TETRAHYDRO-
1,4-PHTHALAZINEDIONE AND 1,8-DINITRO-
5,7,12,14-TETRAHYDROPHTHALAZINO-
[2,3-b]PHTHALAZINE-5,7,12,14-TETRAONE
V. V. Ganzha, A. D. Kotov, T. V. Kesareva, and V. Yu. Orlov
Keywords: hydrazine sulfate, 3-nitrophthalic acid, oxalic acid dihydrazide, derivatives of
1,2,3,4-tetrahydro-1,4-phthalazinedione.
We have observed that when 3-nitrophthalic acid (1) is reacted with hydrazine sulfate or oxalic acid
dihydrazide in fuming sulfuric acid at a temperature of 85-90°C, a mixture of 5-nitro-1,2,3,4-tetrahydro-1,4-
phthalazinedione (2) and 1,8-dinitro-5,7,12,14-tetrahydrophthalazino[2,3-b]phthalazine-5,7,12,14-tetraone (3) is
formed with percentage ratio 80:20 (HPLC data), and at a temperature of 75-80°C the ratio is 30:70.
NO2
O
O
NO2
O
NO2
fuming
CO2H
CO2H
sulfuric acid
N
N
NH
NH
+
.
NH2NH2 H2SO4
or (CON2H3)2
2
1
3
O
O
NO2
O
These aspects were not covered in the papers [1-3], which were devoted to synthesis of phthalazine
derivatives. Obviously the initial step of the reaction is formation of compound 3, which then is converted to
phthalazine 2 under the influence of the reaction conditions. This hypothesis is confirmed by the fact that when
compound 3 is held in fuming sulfuric acid at a temperature of 90°C, it is converted to compound 2.
1
The H NMR spectra were recorded on a Bruker AC-300 SF (300 MHz) spectrometer in DMSO-d6,
internal standard HMDS (δ 0.05 ppm). The IR spectra were recorded on a Specord M-80 (East Germany) in
nujol. The elemental composition was determined on a CHN-1 elemental analyzer (Czech SSR). The mass
spectra were obtained on an MX-1310. High performance liquid chromatography was run on a Hitachi
chromatograph, model L-7100 pump, model L-7400 UV 190-600 detector (254 nm), column (l × d)
250 × 4 mm, support NUCLEOSIL - 100-5 C18, mobile phase 80:20 acetonitrile–water (rate, 1 ml/min), P = 115
bar, solvent for the sample was acetonitrile. As the internal standard, we used 1-chloro-4-nitrobenzene.
Synthesis of Compounds 2 and 3. 3-Nitrophthalic acid (4.7 mmol) was added at room temperature to a
mixture of fuming sulfuric acid (20 ml) and hydrazine sulfate (or oxalic acid dihydrazide) (4.7 mmol). The
reaction mixture was stirred for 8 h at 85-90°C (80°C when oxalic acid dihydrazide was used), cooled down to
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P. G. Demidov Yaroslavl State University, Yaroslavl 150000, Russia; e-mail: kot@bio.uniyar.ac.ru.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1110-1111, July, 2006. Original article
submitted April 13, 2006.
0009-3122/06/4207-0963©2006 Springer Science+Business Media, Inc.
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