Synthesis of 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes and isomeric 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)-yl]benzenes

Article abstract of DOI:10.1016/j.mencom.2009.07.015

The 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes have been synthesized by dehydration of 1,3- and 1,4-bis(2-aminoglyoximo- 1-yl)benzenes followed by oxidation of amino groups. The 1,3- and 1,4-bis(3-nitrofuroxan-4-yl)benzenes have been prepared by nitroz

Full text of DOI:10.1016/j.mencom.2009.07.015

Mendeleev
Communications
Mendeleev Commun., 2009, 19, 217–219
Synthesis of 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes
and isomeric 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)-yl]benzenes
Igor V. Ovchinnikov, Alexey O. Finogenov, Margarita A. Epishina,
Yuri A. Strelenko and Nina N. Makhova*
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
Fax: +7 499 135 5328; e-mail: mnn@ioc.ac.ru
DOI: 10.1016/j.mencom.2009.07.015
The 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes have been synthesized by dehydration of 1,3- and 1,4-bis(2-aminoglyoximo-
1-yl)benzenes followed by oxidation of amino groups. The 1,3- and 1,4-bis(3-nitrofuroxan-4-yl)benzenes have been prepared by
nitrozylation of tetrapotassium salts of 1,3- and 1,4-bis(2,2-dinitro-1-oximinoethyl)benzenes and thermally isomerized to 1,3- and
1,4-bis(4-nitrofuroxan-3-yl)benzenes.
There are two main approaches to the preparation of arylnitro-
furoxans, namely, oxidation of 4-amino-3-arylfuroxans 1 into
Cl
3-aryl-4-nitrofuroxans1 2 and nitrosylation of 1-aryl-2,2-dinitro-
1-oximinoethane dipotassium salts 3 with the formation of
4-aryl-3-nitrofuroxans2 4. The latter can be thermally isomerized
to 3-aryl-4-nitofuroxans2 2 being more preferential in terms
of thermodynamics. Initial 4-amino-3-arylfuroxans 1 are syn-
thesized by thermal isomerization of 3-amino-4-arylfuroxans 5
formed, in turn, through oxidation of 1-amino-2-arylglyoximes
amfi-form 6.3,4 Dehydration of compounds 6 (amfi- and anti- or
syn-forms) under the action of inorganic bases is practiced to
prepare 3-amino-4-arylfurazans5 7, which can be oxidized into
4-aryl-3-nitrofurazans5 8 (Scheme 1).
HC=NOH
ii
C=NOH
CHO
i
HON=C
HON=C
Cl
OHC
H
R
R
R
9a–c
10a–c
11a–c
a 1,3-isomer, R = H
b 1,4-isomer, R = H
c 1,3-isomer, R = 5-Me
NH2 H2N
NC
CN
HON
NOH
iii
iv
11a,b
In this paper, all these approaches were investigated to
prepare isomeric 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)-yl]-
benzenes and their nitrofurazanyl analogues – potential high-
energy compounds. Benzene-1,3(9a)- and 1,4(9b)-dicarboxal-
dehydes, as well as 5-methylbenzene-1,3-dicarboxaldehyde (9c),
were selected as initial compounds. Using known methods,6,7
we transformed dicarboxaldehydes 9a–c to corresponding
oximes 10a–c under the action of hydroxylamine, and com-
pounds 10a–c were treated with gaseous Cl2 in aqueous HCl to
obtain 1,3- and 1,4-bis(hydroximoyl) chlorides 11a–c. To syn-
thesize 1,3- and 1,4-bis(2-aminoglyoximo-1-yl)benzenes 12a,b,
HON
NOH
HON
NOH
12a,b
13a,b
Scheme 2 Reagents and conditions: i, NH2OH·HCl (2 mol), NaOH, MeOH,
40–50 °C, 30 min; ii, Cl2 (2 mol), conc. HCl/MeOH, 0–10 °C, 1 h; iii, KCN
(2 mol), H2O, 20 °C, 1 h; iv, NH4OH·HCl (2 mol)/NaHCO3 (2 mol), H2O,
100 °C, 4 h.
precursors of 1,3- and 1,4-bis[aminofuroxanyl(furazanyl)]-
benzenes, compounds 11a,b were first transformed to 1,3- and
1,4-bis(cyanooximinomethyl) derivatives 13a,b and then treated
with hydroxylamine (Scheme 2).† It could be expected that
compounds 12a,b will mainly have amfi-configuration because
the similar transformation of arylhydroximoyl chlorides results
in a mixture of amfi- and syn-isomers of 1-amino-2-arylglyoximes
with preferential formation of amfi-form.3
The most preferable oxidizers for oxidizing amfi-form of
1-amino-2-arylglyoximes 6 to 3-amino-4-arylfuroxans 5 are
Br2 in hydrochloric acid3 or K3Fe(CN)6 in the presence of bases
(ammonia or aqueous NaOH solution).4(a),(b) Other oxidizers
either badly oxidize (Cl2, CrO3, KMnO4) or do not oxidize
(N2O4, NaOCl, HNO3) 1-amino-2-arylglyoximes into 3-amino-
4-arylfuroxans.8(a),(b) Unfortunately, all our attempts to oxidize
1,3- and 1,4-bis(2-aminoglyoximo-1-yl)benzenes 12a,b to 1,3-
and 1,4-bis(3-aminofuroxan-4-yl)benzenes 14a,b with Br2 in
hydrochloric acid resulted in a complex mixture of the com-
pounds (TLC data), in which the aminofuroxan ring was absent
[signals of C(3) furoxan carbon atoms at 108–110 ppm were
absent from the 13C NMR spectra]. A major part of initial
aminoglyoximes 12a,b decomposed when using K3Fe(CN)6 in
the presence of different bases. It is likely that compounds
Ar
NH2
Ar
NH2
Ar
NH2
[O]
Δ
N
N
N
N
N
N
O
O
O
O
OH
amfi-6
OH
5
1
[O]
NaOH, Δ
Ar
NO2
Ar
NO2
Ar
NH2
Δ
N
N
N
N
N
N
O
O
O
O
O
7
4
2
[O]
NaNO2 AcOH
Ar
NO2
Ar
NO2
N
NO2K
N
N
O K
O
8
3
Scheme 1
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© 2009 Mendeleev Communications. All rights reserved.

Mendeleev Commun., 2009, 19, 217–219
12a,b, which were prepared according to Scheme 2, do not
occur in the amfi-configuration. Therefore, they cannot be
oxidized to aminofuroxans.
H2N
O
N
i
O
N
N
O
12a,b
More successful results were obtained in the synthesis of
nitrofurazanyl derivatives from bis(aminoglyoximes) 12a,b.
These compounds were dehydrated to 1,3- and 1,4-bis(3-amino-
furazan-4-yl)benzenes 15a,b by their refluxing in aqueous
NaOH solution and the amino groups in compounds 15a,b
were then oxidized to the nitro groups with H2O2 in CF3COOH.
Target 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes 16a,b were
synthesized in 56 and 95% yields, respectively (Scheme 3).‡
N
O
NH2
14a,b
ii
H2N
O2N
N
N
O
N
O
N
N
O
N
O
iii
N
N
NH2
15a,b
NO2
16a,b
†
All new compounds exhibited satisfactory elemental analyses. IR spectra
were measured on a UR-20 spectrometer; 1H and 13C NMR spectra were
recorded on Bruker AC200-31 (200 MHz for 1H and 50.3 MHz for 13C)
and Bruker AM300 (300 MHz for 1H and 75.5 MHz for 13C) spectrometers
(CDCl3 was used as the internal standard). 13C NMR spectra were recorded
under proton decoupling conditions. 14N NMR spectra were recorded on
a Bruker AM300 (22 MHz) spectrometer (MeNO2 was used as the
internal standard). Mass spectra were measured on a Finnigan MAT
INCOS-50 instrument. TLC was carried out on Silufol UV-254 plates.
Melting points were measured on a Gallenkamp instrument (Sanyo).
1,3-Bis(2-aminoglyoximo-1-yl)benzene 12a: yield 69%, mp 180–182 °C,
Rf 0.31 (EtOAc). 1H NMR ([2H6]DMSO) d: 5.7 (br. s, 4H, NH2), 7.35 (t,
1H, C5H in Ar, 3J 7.5 Hz), 7.6 (d, 2H, C4H, C6H in Ar, 3J 7.5 Hz), 7.9 (s,
1H, C2H in Ar), 9.45 (br. s, 2H, OH), 11.6 (br. s, 2H, OH). IR (n/cm–1):
3464 (NH2), 3350 (OH), 2850 (CH), 2360, 1652 (C=N), 1484, 1376,
1280, 980, 872, 812, 700.
Scheme 3 Reagents and conditions: i, K3Fe(CN)6 (4 mol), 2.4% aqueous
NH3, H2O, 5 °C, 20 min; ii, 2 N NaOH, 100 °C, 1.5 h; iii, 30% H2O2 (100 mol)/
CF3COOH (25 mol), 50 °C, 2 h.
To obtain 1,3- and 1,4-bis(nitrofuroxanyl)benzenes, the
reaction of all three bis(hydroximoyl) chlorides 11a–c with an
excess of dinitromethane sodium salts at low temperature in
DMF was examined. Sodium salts of 1,3- and 1,4-bis(2,2-di-
nitro-1-oximinoethyl)benzenes (17a–c) were obtained and purified
from dinitromethane by extraction with CHCl3. The salts were
acidified with H2SO4 to 1,3- and 1,4-bis(2,2-dinitro-1-oximino-
ethyl)benzenes 18a–c and transformed to tetrapotassium salts
of 1,3- and 1,4-bis(2,2-dinitro-1-oximinoethyl)benzenes (19a–c)
by treatment with AcOK in MeOH. Nitrosylation of salts 19a–c
with NaNO2 in AcOH afforded 1,3- and 1,4-bis(3-nitrofuroxan-
4-yl)benzenes 20a–c. The reaction evidently runs through inter-
mediates 21a–c. Then, 3-nitrofuroxan derivatives 20a–c were
thermally isomerized to 1,3- and 1,4-bis(4-nitrofuroxan-3-yl)-
benzenes 22a–c in high yields by refluxing in toluene (Scheme 4).§
1,4-Bis(2-aminoglyoximo-1-yl)benzene 12b: yield 31%, mp 214–215 °C,
1
Rf 0.16 (EtOAc). H NMR ([2H6]DMSO) d: 5.76 (br. s, 4H, NH2), 7.56
(s, 4H in Ar), 9.48 (br. s, 2H, OH), 11.70 (br. s, 2H, OH). IR (n/cm–1):
3472 (NH2), 3400 (OH), 3020 (CH), 2980 (CH), 1684 (C=N), 1584,
1416, 1372, 1260, 1140, 1060, 1026, 960, 844, 828.
1,3-Bis(cyanooximinomethyl)benzene 13a: yield 79%, mp 195–196 °C,
Rf 0.38 (CHCl3:EtOAc, 5:1). 1H NMR ([2H6]DMSO) d: 7.65 (t, 1H, C5H
in Ar, 3J 5.9 Hz), 7.85 (d, 2H, C4H, C6H in Ar, 3J 5.9 Hz), 8.05 (s, 1H,
C2H in Ar), 14.00 (s, 2H, OH). IR (n/cm–1): 3384 (OH), 3236 (OH),
3028 (CH), 2988 (CH), 2872 (CH), 2236 (CN), 1612 (C=N), 1440,
1380, 1328, 1256, 1112, 1064, 1016, 896, 864, 800, 620.
NO2 Na
OH
O2N
N
HO
N
i
ii
11a–c
1,4-Bis(cyanooximinomethyl)benzene 13b: yield 90%, mp 192–194 °C,
1
Rf 0.55 (CHCl3:EtOAc, 5:1). H NMR ([2H6]DMSO) d: 7.88 (s, 4H in
Na O2N
R
Ar), 14.1 (br. s, 2H, OH). IR (n/cm–1): 3528 (OH), 3488 (OH), 3008
(CH), 2984 (CH), 2384, 2232 (CN), 1624 (C=N), 1532, 1452, 1304,
1288, 1224, 1072, 1044, 980, 848, 832.
NO2
17a–c
‡
NO2
OH
NO2
K
1,3-Bis(3-aminofurazan-4-yl)benzene 15a: yield 39%, mp 220–221 °C,
O– K+
Rf 0.42 (CHCl3:EtOAc, 1:1). 1H NMR ([2H6]DMSO) d: 6.35 (br. s, 4H,
NH2), 7.7 (t, 1H, C5H in Ar, J 8.6 Hz), 7.9 (d, 2H, C4H, C6H in Ar,
O2N
O2N
3
N
N
HO
N
K O N
3J 8.6 Hz), 8.1 (s, 1H, C2H in Ar). 13C NMR ([2H6]DMSO) d: 126.4 (C1,
C3 in Ar), 126.8, 129.8, 130.1 (C2, C4, C5 and C6 in Ar), 146.5, 155.4
(C3, C4 in furazan ring). IR (n/cm–1): 3472 (NH2), 3244 (CH), 2852
(CH), 2368 (CH), 1632 (C=N), 1572, 1516, 1396, 1280, 980, 872, 812,
700. MS, m/z: 244 (M+).
iii
iv
O2N
K O2N
R
R
NO2
NO2
18a–c
19a–c
O2N
O
N
1,4-Bis(3-aminofurazan-4-yl)benzene 15b: yield 68%, mp 205–207 °C,
Rf 0.32 (CHCl3:EtOAc, 1:1). 1H NMR ([2H6]DMSO) d: 6.30 (br. s, 4H,
NH2), 7.90 (s, 4H, CH in Ar). 13C NMR ([2H6]DMSO) d: 127.15 (C1, C4
in Ar), 128.30 (C2, C3 in Ar), 146.26, 155.24 (C3, C4 in furazan ring).
IR (n/cm–1): 3432 (NH2), 3344 (NH2), 3204, 3201 (CH), 2352 (CH), 1644
(C=N), 1552, 1480, 1388, 1280, 1068, 984, 844, 736. MS, m/z: 244 (M+).
1,3-Bis(3-nitrofurazan-4-yl)benzene 16a: yield 56%, mp 81–83 °C,
NO2
N
O2N
O
O
N
N
O K+
K O
N
N
O
N
v
O
N
O
R
R
O2N NO2
NO2
20a–c
1
Rf 0.26 (CCl4:CHCl3, 1:1). H NMR ([2H6]acetone) d: 7.93 (t, 1H, C5H
21a–c
in Ar, 3J 7.9 Hz), 8.22 (d, 2H, C4H, C6H in Ar, 3J 7.9 Hz), 8.37 (s,
1H, C2H in Ar). 13C NMR (CDCl3) d: 128.71 (C1, C3 in Ar), 129.43,
131.01 (C2, C5 in Ar), 132.83 (C4, C6 in Ar), 149.81 (C4 in furazan ring),
159.01 (C3 in furazan ring). 14N NMR ([2H6]acetone) d: –35.07 (s, NO2).
IR (n/cm–1): 2850 (CH), 2360 (CH), 1652 (C=N), 1540 (NO2), 1484,
1344 (NO2), 1280, 980, 872, 812, 700.
N
O2N
O
O
N
N
O
O
N
vi
R
1,4-Bis(3-nitrofurazan-4-yl)benzene 16b: yield 95%, mp 125–127 °C,
Rf 0.28 (CCl4:CHCl3, 1:1). 1H NMR ([2H6]acetone) d: 8.12 (s, 4H, Ar).
13C NMR ([2H6]acetone) d: 125.99 (C1, C4 in Ar), 130.08 (C2, C3 in
Ar), 149.84 (C4 in furazan ring), 159.79 (C3 in furazan ring). 14N NMR
([2H6]acetone) d: –35.11 (s, NO2). IR (n/cm–1): 3100 (CH), 2850 (CH),
1572, 1544 (NO2), 1372 (NO2), 1224, 1060, 1000, 912, 840, 824, 764.
NO2
22a–c
Scheme 4 Reagents and conditions: i, NaCH(NO2)2 (4 mol), DMF, –20 °C,
48 h; ii, CHCl3; iii, 20% H2SO4; iv, AcOK (10 mol), MeOH, 5 °C, 1 h;
v, NaNO2 (5 mol), AcONa·3H2O, AcOH, 20–30 °C, 30 min; vi, toluene, 2 h.
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Mendeleev Commun., 2009, 19, 217–219
To summarize, 1,3- and 1,4-bis(3-nitrofurazan-4-yl)benzenes
spectra) and elemental analysis data. It was shown that syn-
thesized 1,3- and 1,4-bis(aminoglyoximoyl)benzenes are not
evidently in amfi-configuration that hindered their oxidation to
corresponding 1,3- and 1,4-bis(3-aminofuroxan-4-yl)benzenes.
and isomeric 1,3- and 1,4-bis[3(4)-nitrofuroxan-4(3)yl]benzenes
were for the first time synthesized in this work. Their structures
were established by spectral (1H, 13C, 14N NMR, IR and mass
§
1,3-Bis(3-nitrofuroxan-4-yl)benzene 20a: yield 56%, mp 139.5–140.5 °C,
This study was partially supported by the Presidium of the
Russian Academy of Sciences, the programme ‘Development
of Methods for Synthesizing Chemical Compounds and Creating
New Materials’ (2006–2008).
Rf 0.29 (CCl4:EtOAc, 1:1). 1H NMR ([2H6]acetone) d: 7.92 (t, 1H, C5H
in Ar, 3J 7.9 Hz), 8.15 (d, 2H, C4H, C6H in Ar, 3J 7.9 Hz), 8.28 (s, 1H,
C2H in Ar). 13C NMR ([2H6]acetone) d: 125.42 (C1, C3 in Ar), 127.33
(C3 in furoxan ring), 129.02, 129.82 (C2, C5 in Ar), 132.22 (C4, C6 in
Ar), 151.35 (C4 in furoxan ring). 14N NMR (CDCl3) d: –38.35 (s, NO2).
IR (n/cm–1): 3096 (CH), 1632 (furoxan ring), 1544 (NO2), 1468, 1448,
1392 (NO2), 1264, 1220, 1172, 1040, 1000, 984, 856, 808, 756, 720.
1,4-Bis(3-nitrofuroxan-4-yl)benzene 20b: yield 45%, mp 180–203 °C,
Rf 0.31 (CCl4:EtOAc, 1:1). 1H NMR ([2H6]acetone) d: 8.13 (s, 4H in Ar).
13C NMR (CDCl3) d: 128.17 (C3 in furoxan ring), 129.75 (C1, C4 in Ar),
129.78 (C2, C3, C5 and C6 in Ar), 151.84 (C4 in furoxan ring). 14N NMR
([2H6]acetone) d: –38.30 (s, NO2). IR (n/cm–1): 3112 (CH), 2800 (CH),
2332, 1632 (furoxan ring), 1548 (NO2), 1436, 1340 (NO2), 1200, 1012,
984, 844, 792, 712.
References
1 (a) N. N. Makhova, A. N. Blinnikov and L. I. Khmel’nitskii, Mendeleev
Commun., 1995, 56; (b) I. V. Ovchinnikov, A. N. Blinnikov, N. N. Makhova
and L. I. Khmel’nitskii, Mendeleev Commun., 1995, 58.
2 V. G. Dubonos, I. V. Ovchinnikov, N. N. Makhova and L. I. Khmel’nitskii,
Mendeleev Commun., 1992, 120.
3 A. R. Gagneux and R. Meier, Helv. Chim. Acta, 1970, 53, 1883.
4 (a) C. Lehmann, A. Gagneux and E. Renk, Switzerland Patent, 496721,
1970 (Chem. Abstr., 1971, 75, 20406p); (b) N. N. Makhova and T. I.
Godovikova, Ross. Khim. Zh. (Zh. Ross. Khim. Ob-va im. D. I. Mendeleeva),
1997, 41 (2), 54 [Mendeleev Chem. J. (Engl. Transl.), 1997, 41, 81].
5 A. B. Sheremetev, N. N. Makhova and W. Friedrichsen, Adv. Heterocycl.
Chem., 2001, 78, 66.
1,3-Bis(3-nitrofuroxan-4-yl)-5-methylbenzene 20c: yield 42%, mp 122–
124 °C, Rf 0.20 (CCl4:CHCl3, 1:1). H NMR ([2H6]acetone) d: 2.60 (s,
1
3H, Me), 7.97 (s, 2H in Ar), 8.08 (s, 1H in Ar). 13C NMR (CDCl3) d:
20.33 (Me), 125.73 (C3 in furoxan ring), 127.41 (C5 in Ar), 132.93
(C4, C6 in Ar), 139.72 (C2 in Ar), 151.78 (C4 in furoxan ring). 14N NMR
([2H6]acetone) d: –38.35 (s, NO2). IR (n/cm–1): 2932 (CH), 2876 (CH),
1648 (furoxan ring), 1628 (Ar), 1536 (NO2), 1468, 1412, 1348 (NO2),
1260, 1172, 1076, 880, 844, 776.
6 L. A. Errede and J. M. Hoyt, J. Am. Chem. Soc., 1960, 82, 436.
7 B. H. Kim and E. J. Jeong, Synthesis, 2001, 14, 2119.
8 (a) G. Ponzio and C. Cerrina, Gazz. Chim. Ital., 1928, 58, 26; (b) A. Vianello,
Gazz. Chim. Ital., 1928, 58, 328.
1,3-Bis(4-nitrofuroxan-3-yl)benzene 22a: yield 91%, mp 142–144 °C,
1
Rf 0.21 (CCl4:CHCl3, 1:1). H NMR ([2H6]acetone) d: 7.92 (t, 1H, C5H
in Ar, 3J 7.9 Hz), 8.09 (d, 2H, C4H, C6H in Ar, 3J 7.9 Hz), 8.22 (s, 1H,
C2H in Ar). 13C NMR ([2H6]acetone) d: 110.00 (C3 in furoxan ring),
121.90 (C1, C3 in Ar), 129.53, 131.04 (C2, C5 in Ar), 132.84 (C4, C6 in
Ar), 158.87 (C4 in furoxan ring). 14N NMR (CDCl3) d: –34.88 (s, NO2).
IR (n/cm–1): 1632 (furoxan ring), 1568 (NO2), 1512, 1484, 1372 (NO2),
1296, 1268, 1144, 1116, 1072, 1028, 1000, 988, 896, 828, 796, 792, 704.
1,4-Bis(4-nitrofuroxan-3-yl)benzene 22b: yield 90%, mp 212–214 °C,
Rf 0.20 (CCl4:CHCl3, 1:1). 1H NMR ([2H6]acetone) d: 8.09 (s, 4H in Ar).
13C NMR (CDCl3) d: 110.08 (C3 in furoxan ring), 123.91 (C1, C4 in Ar),
130.23 (C2, C3, C5 and C6 in Ar), 158.85 (C4 in furoxan ring). 14N NMR
([2H6]acetone) d: –34.91 (s, NO2). IR (n/cm–1): 1624 (furoxan ring),
1612 (Ar), 1536 (NO2), 1488, 1408, 1364 (NO2), 1292, 1268, 1132, 1076,
992, 840, 792.
1,3-Bis(4-nitrofuroxan-3-yl)-5-methylbenzene 22c: yield 70%, mp 138–
1
141 °C, Rf 0.20 (CCl4:CHCl3, 1:1). H NMR ([2H6]acetone) d: 2.56 (s,
3H, Me), 7.88 (s, 2H in Ar), 7.99 (s, 1H in Ar). 13C NMR (CDCl3) d:
20.33 (Me), 109.95 (C3 in furoxan ring), 121.81 (C1, C3 in Ar), 128.19
(C2 in Ar), 133.10 (C4, C6 in Ar), 139.80 (C5 in Ar), 158.85 (C4 in
furoxan ring). 14N NMR ([2H6]acetone) d: –35.07 (s, NO2). IR (n/cm–1):
2920 (CH), 1624 (furoxan ring), 1560 (NO2), 1504, 1356 (NO2), 1272,
1136, 1076, 1016, 872, 832, 776, 704.
Received: 5th February 2009; Com. 09/3281
– 219 –