Nitrolysis of N,Nꢀdialkylcarboxamides in liquid CO2 Russ.Chem.Bull., Int.Ed., Vol. 59, No. 11, November, 2010 2149
Scheme 4
N,NꢀDiethylnitramine (2a). B.p. 99—100 °C (18 Torr)
20
(cf. Ref. 12: b.p. 90—91 °C (14 Torr)); nD 1.4522. IR (NaCl),
ν/cm–1: 2984, 2936, 1500, 1452, 1376, 1276, 1084. 1H NMR
(CDCl3), δ: 1.29 (t, 6 H, Me, J = 6.9 Hz); 3.82 (q, 4 H, NCH2,
J = 6.9 Hz).
N,NꢀDimethylnitramine (2b). B.p. 57—58 °C (cf. Ref. 12:
b.p. 55.5—56.5 °C). IR (KBr), ν/cm–1: 3112, 2944, 1500, 1416,
1336, 1280, 1068. 1H NMR (CDCl3), δ: 3.42 (s, 6 H, NMe).
N,NꢀDiꢀnꢀbutylnitramine (2c). B.p. 142—143 °C (18 Torr)
(cf. Ref. 11: b.p. 123—124 °C (9 Torr)); nD20 1.4564. IR (NaCl),
ν/cm–1: 2960, 2872, 1512, 1464, 1384, 1284, 1112. 1H NMR
(CDCl3), δ: 0.94 (t, 6 H, Me, J = 7.0 Hz); 1.33 (m, 4 H, CH2);
1.64 (m, 4 H, CH2); 3.70 (t, 4 H, NCH2, J = 7.3 Hz).
NꢀNitromorpholine (2d). B.p. 50—51 °C (cf. Ref. 13: b.p.
51—52 °C). IR (KBr), ν/cm–1: 2984, 2872, 1512, 1380, 1312,
1256, 1116, 980, 864. 1H NMR (CDCl3), δ: 3.82 (s, 8 H, CH2).
Reagents and conditions: i. N2O5 (3 equiv.), 100% HNO3
(4 equiv.), CO2 (100 bar), 0—20 °C, 4 h.
cinogenic side products, Nꢀnitrosoamines, are the advanꢀ
tages of the suggested procedure.
NꢀNitropiperidine (2e). B.p. 121—122 °C (18 Torr) (cf. Ref. 12:
b.p. 116—117 °C (17 Torr)), nD 1.4953. IR (NaCl), ν/cm–1
:
20
Experimental
2944, 2868, 1512, 1444, 1384, 1328, 1276, 1064. 1H NMR
(CDCl3), δ: 1.52 (q, 2 H, CH2, J = 6.0 Hz); 1.68 (m, 4 H, CH2);
3.82 (t, 4 H, NCH2, J = 6.0 Hz).
1,4ꢀDinitropiperazine (2f). B.p. 214—215 °C (cf. Ref. 11:
b.p. 215—216 °C). IR (KBr), ν/cm–1: 2984, 2888, 1556, 1448,
1388, 1244, 1096, 960. 1H NMR (DMSOꢀd6), δ: 4.06 (s, 8 H, CH2).
1ꢀAcetylꢀ3,5ꢀdinitrohexahydroꢀ1,3,5ꢀtriazine (6). B.p.
156—157 °C (cf. Ref. 39: b.p. 158—159 °C). 1H NMR (DMSOꢀd6),
δ: 2.17 (s, 3 H, C(O)CH3); 5.64 (s, 4 H, N(NO2)CH2NAc); 6.14
(s, 2 H, N(NO2)CH2NNO2).
1
H NMR spectra were recorded on a Bruker AMꢀ300 instruꢀ
ment (300 MHz) in CDCl3 or DMSOꢀd6 relative to Me4Si as
internal standard. Dichloromethane, N,Nꢀdimethylacetamide,
N,Nꢀdimethylformamide were distilled prior to use. N,NꢀDiꢀ
alkylacetamides 1a,c—f and N,Nꢀdialkylformamides 3a,c—e
were synthesized by the known methods.36 1,4ꢀDiformylpiperꢀ
azine,11 1,3,5ꢀtriacetylhexahydroꢀ1,3,5ꢀtriazine,37 and N2O5
(see Ref. 38) were prepared according to the previously described
procedures.
The nitrolysis of N,Nꢀdiethylacetamide (1a) with N2O5 in liquid
CO2. A steel autoclave (V = 35 mL) containing N,Nꢀdiethylaceꢀ
tamide (1a) (1.15 g, 10 mmol) was filled with CO2 (60 bar) and
cooled to 0 °C. Then N2O5 was added with stirring (see Table 1,
entries 1—3), the reaction mixture was heated up to 20 °C, and
the pressure of CO2 was increased up to 80 bar. The reaction
mixture was stirred for 4 h, CO2 was removed, and the residue
was poured into ice water (50 mL). The product was extracted
with CH2Cl2 (4×10 mL), combined organic layers were washed
with a saturated aqueous solution of NaHCO3 (2×20 mL), water
(25 mL), and dried with Na2SO4. Removal of the solvent in vacuo
afforded nitramine 2a (the yield is given in Table 1). Physicoꢀ
chemical parameters and spectral characteristics of 2a are conꢀ
References
1. T. Urbanski, Chemistry and Technology of Explosives, Vol. 1,
Pergamon Press, Oxford, 1965.
2. E. Yu. Orlova, Khimiya i tekhnologiya brizantnykh vzryvꢀ
chatykh veshchestv [Chemistry and Technology of Blasting
Explosives], 3d ed., Khimiya, Leningrad, 1991, 432 pp.
(in Russian).
3. Energeticheskie kondensirovannye sistemy: Kratkii entsiklopeꢀ
dicheskii slovar´ [HighꢀEnergy Fused Energetic Systems: A Brief
Encyclopedia], Ed. B. P. Zhukov, Yuanus, Moscow, 2000,
596 pp. (in Russian).
4. R. Mayer, Explosives, 5th ed. (Electronic), WileyꢀVCH Verꢀ
lag, GmbH, 2002.
5. D. O’Meara, D. M. Shepherd, J. Chem. Soc., 1955, 4232.
6. H. H. Licht, H. Ritter, Propell. Explos. Pyrotech., 1985,
10, 147.
7. W. E. Bachmann, W. J. Horton, E. L. Jenner, N. W. Macꢀ
Naughton, C. E. Maxwell, J. Am. Chem. Soc., 1950, 72, 3132.
8. J. P. Agrawal, M. Sonawane, S. H. Sonawane, R. N. Surve,
J. Hazard. Mater., 2000, 77, 11.
sistent with that previously published35
.
The nitrolysis of N,Nꢀdiethylacetamide (1a) with a mixture of
N2O5 and 100% HNO3 in liquid CO2. A steel autoclave (V = 35 mL)
containing N,Nꢀdiethylacetamide (1a) (1.15 g, 10 mmol) was
filled with CO2 (60 bar) and then cooled to 0 °C. A mixture of
N2O5 and 100% HNO3 was added with stirring (see Table 1,
entries 4—6). The reaction was carried out and the product was
isolated as described above. Removal of the solvent in vacuo
afforded nitramine 2a (the yield is given in Table 1).
Synthesis of nitramines 2 and 6 (general procedure). A steel
autoclave (V = 35 mL) containing amide 1b—e, 3a—e (10 mmol)
or cyclic amide 1f, 3f, 5 (5 mmol) was filled with CO2 (60 bar)
and cooled to 0 °C. A mixture of N2O5 (1.62 g, 15 mmol) and
100% HNO3 (1.26 g, 20 mmol) was added with stirring. The
reaction was carried out and the product was isolated as deꢀ
scribed above. Removal of the solvent in vacuo afforded nitrꢀ
amines 2a—e (the yields are given in Table 2). Compounds 2f
and 6 were filtered off, successively washed with ethanol (5 mL),
diethyl ether (5 mL), and air dried (the yields are given on
Schemes 3 and 4).
9. G. A. Olah, R. Malhotra, S. C. Narang, Nitration: Methods
and Mechanisms, WileyꢀVCH, Weinheim, 1989.
10. R. L. Willer, J. Org. Chem., 1984, 49, 5150.
11. J. H. Robson, J. Reinhart, J. Am. Chem. Soc., 1955, 77, 2453.
12. J. H. Robson, J. Am. Chem. Soc., 1955, 77, 107.
13. W. J. Chute, G. E. Dunn, J. C. MacKenzie, G. S. Myers,
G. N. R. Smart, J. W. Suggitt, G. F. Wright, Can. J. Res.,
1948, 26B, 114.
14. Yu. V. Guk, M. A. Ilyushin, E. L. Golod, B. V. Gidaspov,
Usp. Khim., 1983, 52, 499 [Russ. Chem. Rev. (Engl. Transl.),
1983, 52].