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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 9| September 2015| Page o634
https://doi.org/10.1107/S2056989015013432

Crystal structure of 4,5-di­nitro-1H-imidazole

CROSSMARK_Color_square_no_text.svg
G. Kenneth Windler,a Brian L. Scott,b Neil C. Tomsonb and Philip W. Leonarda*

aPO Box 1663 MS C920, Los Alamos National Laboratory, Los Alamos, NM 87544, USA, and bPO Box 1663 MS J514, Los Alamos National Laboratory, Los Alamos, NM 87544, USA
*Correspondence e-mail: philipl@lanl.gov

Edited by G. Smith, Queensland University of Technology, Australia (Received 6 June 2015; accepted 13 July 2015; online 6 August 2015)

The title compound, C3H2N4O4, forms crystals with two mol­ecules in the asymmetric unit which are conformationally similar. With the exception of the O atoms of the nitro groups, the mol­ecules are essentially planar. In the crystal, adjacent mol­ecules are associated by N—H⋯N hydrogen bonds involving the imidazole N—H donors and N-atom acceptors of the unsaturated nitro­gen of neighboring rings, forming layers parallel to (010).

CCDC reference: 1412685

Similar articles

1. Related literature

For background to imidazoles and the title compound, see: Windaus & Vogt (1907[Windaus, A. & Vogt, W. (1907). Ber. Dtsch. Chem. Ges. 40, 3691-3695.]); Cooper (1996[Cooper, P. W. (1996). In Explosives Engineering. New York: Wiley-VCH.]); Epishina et al. (1967[Epishina, L. V., Slovetskii, V. I., Osipov, V. G., Lebedev, O. V., Khmel'nitskii, L. I., Sevost'yanova, V. V. & Novikova, T. S. (1967). Khim. Geterotsikl. Soedin. 4, 716-723.]). For the preparation, see: Novikov et al. (1970[Novikov, S. S., Khmel'nitskii, L. I., Lebedev, O. V., Epishina, L. V. & Sevost'yanova, V. V. (1970). Khim. Geterotsikl. Soedin. 5, 664-668.]). For similar structures, see: Parrish et al. (2015[Parrish, D. A., Kramer, S., Windler, G. K., Chavez, D. E. & Leonard, P. W. (2015). Acta Cryst. E71, o491.]); Windler et al. (2015[Windler, G. K., Scott, B. L., Tomson, N. C. & Leonard, P. W. (2015). Acta Cryst. E71, o633.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C3H2N4O4

  • Mr = 158.09

  • Monoclinic, P 21 /n

  • a = 11.4797 (9) Å

  • b = 8.8205 (7) Å

  • c = 11.802 (1) Å

  • β = 107.827 (1)°

  • V = 1137.65 (16) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.17 mm−1

  • T = 100 K

  • 0.12 × 0.06 × 0.06 mm

2.2. Data collection

  • Bruker D8 Quest with CMOS diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.971, Tmax = 0.995

  • 25837 measured reflections

  • 4868 independent reflections

  • 4216 reflections with I > 2σ(I)

  • Rint = 0.024

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.118

  • S = 1.60

  • 4868 reflections

  • 211 parameters

  • All H-atom parameters refined

  • Δρmax = 0.54 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N3—H2⋯N7i 0.90 (2) 1.96 (2) 2.836 (1) 163 (2)
N8—H4⋯N4ii 0.92 (2) 1.89 (2) 2.807 (1) 179 (3)
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: CHEMDRAW Ultra (Cambridge Soft, 2014[Cambridge Soft (2014). CHEMDRAW Ultra. Cambridge Soft Corporation, Cambridge, Massachusetts, USA.]).

Supporting information

CCDC reference: 1412685

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015013432/zs2338sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015013432/zs2338Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015013432/zs2338Isup3.cdx

Supporting information file. DOI: https://doi.org/10.1107/S2056989015013432/zs2338Isup4.cml

checkCIF report


Comment top

In addition to more mundane uses as pharmaceuticals (Windaus & Vogt, 1907), imidazoles make quality backbones for energetic materials (Epishina et al., 1967) because of their nitrogen content. The dinitro-bearing title compound, C3H2N4O4, is of interest because of its better oxygen balance (Cooper, 1996), contributing to its effectiveness as an explosive. To better understand the nature of explosive sensitivity as it relates to intermolecular forces, the title compound (Fig. 1) was of interest for comparison with other imidazoles previously studied (Parrish et al., 2015; Windler et al., 2015).

In the title compound, the two independent molecules (A, defined by C1–N3 and B, defined by C4–N7) in the asymmetric unit (Fig. 1) are conformationally similar with the nitro groups being variously rotated out of the imidazole planes: in A [torsion angles N3—C1—N1—O2, -174.29 (9)° and N4—C3—N2—O3, 163.63 (7)°] and in B [torsion angles N7—C4—N5—O6, 156.95 (8)° and N6—C6—N6—O7, 163.63 (7)°].

In the crystal, intermolecular N—H···N hydrogen bonding interactions N3—H···N7 and N8—H···N4 between the A and B molecules (Table 1), generate layered structures lying roughly parallel to (010) (Fig. 2).

Related literature top

For background to imidazoles and the title compound, see: Windaus & Vogt (1907); Cooper (1996); Epishina et al. (1967). For the preparation, see: Novikov et al. (1970). For similar structures, see: Parrish et al. (2015); Windler et al. (2015).

Experimental top

Caution! The title compound is an explosive and should only be handled with appropriate safety equipment in small quantities by an experienced explosive handler.

The title compound was prepared by literature methods (Novikov et al., 1970). Crystals were obtained by slow evaporation of a concentrated solution in ethyl acetate.

Refinement top

All hydrogen atoms was located in a difference-Fourier and the positional parameters were fully refined, with Uiso(H) set invariant at 0.08.

Structure description top

In addition to more mundane uses as pharmaceuticals (Windaus & Vogt, 1907), imidazoles make quality backbones for energetic materials (Epishina et al., 1967) because of their nitrogen content. The dinitro-bearing title compound, C3H2N4O4, is of interest because of its better oxygen balance (Cooper, 1996), contributing to its effectiveness as an explosive. To better understand the nature of explosive sensitivity as it relates to intermolecular forces, the title compound (Fig. 1) was of interest for comparison with other imidazoles previously studied (Parrish et al., 2015; Windler et al., 2015).

In the title compound, the two independent molecules (A, defined by C1–N3 and B, defined by C4–N7) in the asymmetric unit (Fig. 1) are conformationally similar with the nitro groups being variously rotated out of the imidazole planes: in A [torsion angles N3—C1—N1—O2, -174.29 (9)° and N4—C3—N2—O3, 163.63 (7)°] and in B [torsion angles N7—C4—N5—O6, 156.95 (8)° and N6—C6—N6—O7, 163.63 (7)°].

In the crystal, intermolecular N—H···N hydrogen bonding interactions N3—H···N7 and N8—H···N4 between the A and B molecules (Table 1), generate layered structures lying roughly parallel to (010) (Fig. 2).

For background to imidazoles and the title compound, see: Windaus & Vogt (1907); Cooper (1996); Epishina et al. (1967). For the preparation, see: Novikov et al. (1970). For similar structures, see: Parrish et al. (2015); Windler et al. (2015).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), Mercury (Macrae et al., 2008) and PLATON (Spek, 2009); software used to prepare material for publication: CHEMDRAW Ultra (Cambridge Soft, 2014).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with atom labeling. Ellipsoids are drawn at the 50% probability level and the hydrogen atoms are drawn as spheres of arbitrary size.
[Figure 2] Fig. 2. A crystal packing diagram for the title compound viewed along the b axis. The N—H···N hydrogen bonds are shown as dashed lines.
4,5-Dinitro-1H-imidazole top
Crystal data top
C3H2N4O4F(000) = 640
Mr = 158.09Dx = 1.846 Mg m−3
Monoclinic, P21/nMelting point = 460–461 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 11.4797 (9) ÅCell parameters from 4868 reflections
b = 8.8205 (7) Åθ = 2.9–35.4°
c = 11.802 (1) ŵ = 0.17 mm−1
β = 107.827 (1)°T = 100 K
V = 1137.65 (16) Å3Block, colorless
Z = 80.12 × 0.06 × 0.06 mm
Data collection top
Bruker D8 Quest with CMOS
diffractometer		4868 independent reflections
Radiation source: fine-focus sealed tube4216 reflections with I > 2σ(I)
Bruker Triumph curved graphite monochromatorRint = 0.024
ω scansθmax = 35.4°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		h = −17→18
Tmin = 0.971, Tmax = 0.995k = −14→13
25837 measured reflectionsl = −18→18
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118All H-atom parameters refined
S = 1.60 w = 1/[σ2(Fo2) + (0.0548P)2]
where P = (Fo2 + 2Fc2)/3
4868 reflections(Δ/σ)max = 0.001
211 parametersΔρmax = 0.54 e Å−3
0 restraintsΔρmin = −0.33 e Å−3
Crystal data top
C3H2N4O4V = 1137.65 (16) Å3
Mr = 158.09Z = 8
Monoclinic, P21/nMo Kα radiation
a = 11.4797 (9) ŵ = 0.17 mm−1
b = 8.8205 (7) ÅT = 100 K
c = 11.802 (1) Å0.12 × 0.06 × 0.06 mm
β = 107.827 (1)°
Data collection top
Bruker D8 Quest with CMOS
diffractometer		4868 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		4216 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.995Rint = 0.024
25837 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.118All H-atom parameters refined
S = 1.60Δρmax = 0.54 e Å−3
4868 reflectionsΔρmin = −0.33 e Å−3
211 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.29370 (6)0.50168 (8)0.81909 (6)0.01298 (13)
N20.15331 (6)0.38337 (8)1.01582 (6)0.01315 (13)
N30.11402 (6)0.37089 (8)0.70000 (6)0.01075 (12)
N40.01562 (6)0.30341 (8)0.82719 (6)0.01203 (13)
N50.51594 (6)0.79131 (8)0.14048 (6)0.01209 (13)
N60.33377 (6)0.62492 (8)0.27135 (6)0.01158 (12)
N70.31591 (6)0.85813 (8)0.01033 (6)0.01174 (12)
N80.19372 (6)0.75974 (8)0.10560 (6)0.01083 (12)
O10.31536 (6)0.52596 (8)0.72497 (6)0.02044 (14)
O20.35443 (7)0.54920 (9)0.91643 (6)0.02736 (17)
O30.25949 (6)0.41102 (8)1.07370 (6)0.01982 (14)
O40.06957 (6)0.36304 (9)1.05882 (6)0.02084 (14)
O50.55956 (6)0.80860 (9)0.05851 (6)0.02079 (14)
O60.57642 (6)0.78190 (8)0.24607 (5)0.01798 (13)
O70.43309 (5)0.56137 (7)0.30593 (6)0.01585 (12)
O80.24913 (6)0.60769 (8)0.31361 (6)0.01785 (13)
C10.18544 (7)0.41388 (8)0.81011 (6)0.01016 (13)
C20.01380 (7)0.30381 (9)0.71412 (7)0.01240 (14)
C30.12271 (7)0.37018 (8)0.88769 (6)0.01062 (13)
C40.38434 (7)0.78740 (8)0.11035 (6)0.01003 (13)
C50.20090 (7)0.83961 (9)0.01039 (7)0.01204 (14)
C60.31069 (7)0.72465 (8)0.17067 (6)0.00992 (13)
H1−0.044 (2)0.259 (3)0.651 (2)0.080*
H20.129 (2)0.386 (3)0.630 (2)0.080*
H30.133 (2)0.875 (3)−0.045 (2)0.080*
H40.125 (2)0.740 (3)0.1274 (19)0.080*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0108 (3)0.0118 (3)0.0163 (3)−0.0018 (2)0.0041 (2)−0.0016 (2)
N20.0163 (3)0.0130 (3)0.0101 (3)0.0017 (2)0.0039 (2)0.0008 (2)
N30.0099 (3)0.0133 (3)0.0102 (3)−0.0015 (2)0.0047 (2)−0.0021 (2)
N40.0110 (3)0.0151 (3)0.0109 (3)−0.0013 (2)0.0047 (2)−0.0008 (2)
N50.0099 (3)0.0128 (3)0.0138 (3)−0.0012 (2)0.0039 (2)0.0000 (2)
N60.0119 (3)0.0126 (3)0.0100 (3)−0.0010 (2)0.0031 (2)0.0009 (2)
N70.0108 (3)0.0154 (3)0.0098 (3)0.0015 (2)0.0042 (2)0.0018 (2)
N80.0089 (3)0.0147 (3)0.0096 (3)0.0004 (2)0.0038 (2)0.0005 (2)
O10.0205 (3)0.0243 (3)0.0221 (3)−0.0084 (2)0.0147 (2)−0.0065 (2)
O20.0271 (4)0.0329 (4)0.0170 (3)−0.0173 (3)−0.0009 (3)−0.0019 (3)
O30.0195 (3)0.0229 (3)0.0135 (3)−0.0047 (2)−0.0003 (2)−0.0017 (2)
O40.0197 (3)0.0315 (4)0.0139 (3)0.0045 (3)0.0091 (2)0.0044 (2)
O50.0135 (3)0.0340 (4)0.0182 (3)−0.0032 (2)0.0097 (2)−0.0037 (2)
O60.0123 (3)0.0222 (3)0.0156 (3)−0.0039 (2)−0.0014 (2)0.0056 (2)
O70.0114 (2)0.0170 (3)0.0171 (3)0.0014 (2)0.0013 (2)0.0044 (2)
O80.0166 (3)0.0229 (3)0.0173 (3)0.0010 (2)0.0099 (2)0.0062 (2)
C10.0093 (3)0.0104 (3)0.0113 (3)−0.0006 (2)0.0039 (2)−0.0013 (2)
C20.0105 (3)0.0162 (3)0.0118 (3)−0.0022 (2)0.0053 (2)−0.0021 (2)
C30.0111 (3)0.0118 (3)0.0093 (3)0.0004 (2)0.0037 (2)−0.0004 (2)
C40.0086 (3)0.0120 (3)0.0097 (3)0.0000 (2)0.0031 (2)−0.0006 (2)
C50.0109 (3)0.0157 (3)0.0100 (3)0.0021 (2)0.0040 (2)0.0016 (2)
C60.0095 (3)0.0121 (3)0.0080 (3)0.0000 (2)0.0025 (2)0.0005 (2)
Geometric parameters (Å, º) top
O1—N11.2291 (10)N4—C31.3530 (11)
O2—N11.2211 (10)N3—H20.90 (2)
O3—N21.2256 (10)N5—C41.4426 (11)
O4—N21.2299 (10)N6—C61.4364 (10)
O5—N51.2274 (10)N7—C51.3306 (11)
O6—N51.2297 (9)N7—C41.3535 (10)
O7—N61.2230 (10)N8—C61.3628 (11)
O8—N61.2299 (10)N8—C51.3500 (11)
N1—C11.4404 (11)N8—H40.92 (2)
N2—C31.4486 (10)C1—C31.3817 (11)
N3—C11.3610 (10)C2—H10.92 (2)
N3—C21.3487 (11)C4—C61.3771 (11)
N4—C21.3282 (10)C5—H30.91 (2)
O1—N1—O2125.12 (8)C6—N8—H4125.6 (14)
O1—N1—C1115.84 (7)N1—C1—C3135.58 (7)
O2—N1—C1119.01 (7)N3—C1—C3105.73 (7)
O3—N2—O4124.66 (7)N1—C1—N3118.30 (6)
O3—N2—C3118.67 (7)N3—C2—N4111.94 (7)
O4—N2—C3116.66 (7)N2—C3—C1131.32 (7)
C1—N3—C2106.95 (7)N4—C3—C1110.21 (6)
C2—N4—C3105.15 (7)N2—C3—N4118.47 (7)
C1—N3—H2127.2 (15)N3—C2—H1121.3 (15)
C2—N3—H2125.9 (15)N4—C2—H1126.7 (15)
O5—N5—C4117.25 (7)N7—C4—C6110.60 (7)
O6—N5—C4118.16 (7)N5—C4—N7119.23 (7)
O5—N5—O6124.55 (8)N5—C4—C6130.13 (7)
O8—N6—C6116.27 (7)N7—C5—N8112.21 (7)
O7—N6—C6118.28 (7)N8—C6—C4105.81 (6)
O7—N6—O8125.42 (7)N6—C6—N8120.37 (7)
C4—N7—C5104.72 (7)N6—C6—C4133.38 (7)
C5—N8—C6106.67 (7)N7—C5—H3126.3 (15)
C5—N8—H4127.5 (14)N8—C5—H3121.5 (15)
O1—N1—C1—N3−2.71 (11)O7—N6—C6—N8159.07 (7)
O1—N1—C1—C3−174.29 (9)O7—N6—C6—C4−12.11 (12)
O2—N1—C1—N3175.41 (8)O8—N6—C6—N8−18.96 (10)
O2—N1—C1—C33.83 (14)O8—N6—C6—C4169.86 (8)
O3—N2—C3—N4163.63 (7)C4—N7—C5—N8−0.32 (9)
O3—N2—C3—C1−15.76 (12)C5—N7—C4—N5−177.47 (7)
O4—N2—C3—N4−15.16 (11)C5—N7—C4—C60.55 (9)
O4—N2—C3—C1165.45 (8)C5—N8—C6—N6−173.00 (7)
C2—N3—C1—N1−174.24 (7)C5—N8—C6—C40.35 (8)
C2—N3—C1—C3−0.35 (8)C6—N8—C5—N7−0.02 (9)
C1—N3—C2—N41.06 (9)N3—C1—C3—N4−0.44 (9)
C3—N4—C2—N3−1.31 (9)N1—C1—C3—N2−8.71 (15)
C2—N4—C3—N2−178.45 (7)N1—C1—C3—N4171.86 (8)
C2—N4—C3—C11.06 (9)N3—C1—C3—N2178.98 (8)
O6—N5—C4—C6−25.25 (12)N5—C4—C6—N6−10.74 (14)
O5—N5—C4—N7−25.48 (11)N5—C4—C6—N8177.17 (7)
O5—N5—C4—C6156.95 (8)N7—C4—C6—N6171.53 (8)
O6—N5—C4—N7152.33 (7)N7—C4—C6—N8−0.57 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H2···N7i0.90 (2)1.96 (2)2.836 (1)163 (2)
N8—H4···N4ii0.92 (2)1.89 (2)2.807 (1)179 (3)
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x, −y+1, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H2···N7i0.90 (2)1.96 (2)2.836 (1)163 (2)
N8—H4···N4ii0.92 (2)1.89 (2)2.807 (1)179 (3)
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x, −y+1, −z+1.
 

Acknowledgements

This work was supported by the National Nuclear Security Administration Science Campaign 2 and performed at Los Alamos National Laboratory under DE-AC52-06 N A25396. LA-UR-15-23929

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ISSN: 2056-9890
Volume 71| Part 9| September 2015| Page o634
https://doi.org/10.1107/S2056989015013432
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