Condensation of acetamide in aqueous solutions in the presence of sulfur(IV) dioxide

Full text of DOI:10.1134/S107036320906036X

ISSN 1070-3632, Russian Journal of General Chemistry, 2009, Vol. 79, No. 6, pp. 1223–1224. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © R.E. Khoma, A.V. Mazepa, A.A. Shestaka, A.A. Ennann, V.O. Gelmboldt, 2009, published in Zhurnal Obshchei Khimii, 2009,
Vol. 79, No. 6, pp. 1048–1049.
LETTERS
TO THE EDITOR
Condensation of Acetamide in Aqueous Solutions
in the Presence of Sulfur(IV) Dioxide
R. E. Khomaa,b, A. V. Mazepac, A. A. Shestakab, A. A. Ennannb, and V. O. Gelmboldtb
a Mechnikov Odessa National University,
ul. Dvoryanskaya 2, Odessa 65082, Ukraine
e-mail: rek@onu.edu.ua, r_khoma@farlep.net
b Physico-Chemical Institute of Environment and Human Protection,
Ministry of Education and Sciences of Ukraine and National Academy of Sciences of Ukraine, Odessa, Ukraine
c Bogatskii Physico-Chemical Institute, National Academy of Sciences of Ukraine, Odessa, Ukraine
Received December 10, 2008
DOI: 10.1134/S107036320906036X
The reactions leading to formation of cyclic
structures are not typical for amides, in distinct to their
thio analogs that under the conditions of acid catalyzed
hydrolysis are prone to cyclization processes with
formation of N,S-containing heterocycles [1–3].
SO2 with the rate 10 to 15 ml min–1 until homogenous
mixture has formed. The viscous oily yellow solution
as placed to a freezing chamber (≈ –15°С). After a few
weeks the SO2 excess was neutralized at –5 to –10°С
by adding Na2CO3 in small portions until gas evolution
stopped. The solution was decanted and again placed
into freezing chamber (~ –15°С). After ~14 days the
solution obtained was placed to a desiccator over
calcium chloride at room temperature and kept until a
precipitate has fiormed. We isolated 5.2 g (62 %) of
product І, white, easily sublimating at room
temperature. The IR spectrum, ν, cm–1: 3420 m
[νas(NH)]; 3342 s [νs(NH)]; 3080 sh [νas(СH2)(=CH2)];
2930 s [νs(СH2)(=CH2)]; 2857 s [νs(СH2)]; 1637 m
[ν(СО), ν(С=С)]; 1562 s [δ(NH2), [ν(С=С)ring]; 1453 s
[δ(СH2), δ(СNН)]; 1397 m [δ(СH2)planar.]; 1361 m
[δ(СH2), r(NH2)]; 1071 w [νas(СN)(C–NH2)]; 1061 m
[δ(ССC)planar,ring ]; 969 w [νring]; 823 m, br [t(NH2)];
797 m [δ(СH2)]; 733 m [δ(ССC)out-of-plane, ring]; 711 m
[r (СH2), t(NH2)]; 611 m [δ(ССC)out-of-plane, ring]; 497 m
We found that reaction of acetamide proceeding in
SO2–H3СC(О)NH2–H2O solution affords cyclic o-
quinoid compound І that formally can be regarded as a
product of acetamide condensation along the scheme:
NH2
O
O
SO2
NH2
6
H2N
NH2
O
NH2
I
+ 4 H2O + 2 NH3
In the process of the synthesis of І also has been
registered formation of acetic acid that can be a result
of acetamide hydrolysis in the presence of SO2. Not
excluded that the ability of the observed trans-
formation in the presence of SO2 is provided due to
weak СН-acid properties of Н3СС(О)NH2 [1].
1
[δ(ОСС)ring ]. The Н NMR spectrum (CD3OD), δ,
ppm (J, Hz): 1.33–1.37 m (4H, C–NH2), 1.44–1.53 m
(4Н, CH2–NH2) 2.63 t (4Н, CH2–NH2, JНН 7.2), 4.87 s
(4H, C=СH2). The mass spectrum (FAB, solution of I
in 3-nitrobenzyl alcohol), m/z (Irel %): 250 (100) [M +
2Н]+; (FAB, solution of I in 3-nitrobenzyl alcohol with
NaI adding) m/z (Irel, %): 271 (65) [M + Na]+, 250 (53)
[M + 2Н]+. In the FAB mass-spectrum occurs a peak
of [M + 2Н]+, characteristic of o-quinones that are
reduced to the corresponding catechols, that is not
inherent in p-quinones [5]. Found, %: C 57.43; H 6.41;
4,5-Bis(aminomethyl)-3,6-bis(1-aminovinyl)cyclo-
hexa-3,5-diene-1,2-dione (І). A mixture of acetamide
(0.2 mol) and 3.6 ml of water (0.2 mol) was placed to a
reactor, cooled and kept at the temperature 0°С for
20 min. Then through the mixture was passed gaseous
1223

1224
KHOMA et al.
N 23.21. C12H16N4O2. Calculated, %: C 58.05; H 6.50;
REFERENCES
N 22.57. M 248.3.
1. Comprehensive Organic Chemistry, Barton, D. and
Ollis, W.D., Eds., vol. 4, Liverpool: Pergamon Press,
1979. Translated under the title Obshchaya orga-
nicheskaya khimiya, Moscow: Khimiya, 1983.
The carbon and hydrogen contents were analyzed
on a СHN-analyzer. The IR spectra were recorded on a
Spectrum BX II FT-IR System instrument (Perkin-
Elmer) in the range 4000–350 cm–1, the samples were
2. Ibid., vol. 5, p. 656.
3. Ibid., vol. 9, p. 548.
4. Gel’mbol’dt, V.O., Ilyukhin, A.B., Ganin, E.V., and
Ennan, A.A., Koord. Khimiya, 2001, vol. 27, p. 573.
5. Vul’fson, N.S., Zaikin, V.G., and Mikaya, A.I., Mass-
spektrometriya organicheskikh soedinenii (Mass-
Spectrometry of Organic Compounds), Moscow:
Khimiya, 1986.
prepared as pellets with KBr. The H, 13C NMR
1
spectra were registered on a Bruker WM 400 spec-
trometer. The FAB mass spectra were registered on a
VG 7070 instrument, desorption of ions from a liquid
matrix was carried out by the action of the beam of
argon atoms with the energy 8 keV.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 6 2009