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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 67| Part 6| June 2011| Page o1369
doi:10.1107/S1600536811015996

3,4-Di­nitro-1H-pyrazole benzene 0.25-solvate

Yong-Xiang Li,a Shan Dua and Jian-Long Wanga*

aSchool of Chemical Engineering and Environment, North University of China, Taiyuan, People's Republic of China
*Correspondence e-mail: wangjianlong@nuc.edu.cn

(Received 11 April 2011; accepted 27 April 2011; online 11 May 2011)

The asymmetric unit of the title compound, 4C3H2N2O4·C6H6, contains two independent dinitro­pyrazole mol­ecules and half a benzene solvent mol­ecule, which lies on a crystallographic inversion centre. Each pyrazole ring is essentially planar (mean deviations of 0.009 and 0.002 Å), with the two nitro groups rotated out of the plane [dihedral angles = 11.7 (2)/31.1 (1) and 21.8 (2)/25.0 (1)° for the two mol­ecules].

Related literature

For the biological properties of polynitro­pyrazoles, see: Alejandre-Durán et al. (1986[Alejandre-Durán, E., Ruiz-Rubio, M., Claramunt, R. M., López, C. & Pueyo, C. (1986). Environ. Mutagen. 8, 611-619.]); Grigor'ev et al. (1998)[Grigor'ev, N. B., Kalinkina, M. A., Chechekin, G. V., Nikitin, V. B. & Engalycheva, G. N. (1998). Pharm. Chem. J. 32, 127-131.]; Xuan et al. (1999[Xuan, B., Zhou, Y. H. & Verma, R. S. (1999). J. Ocul. Pharmacol. Ther. 15, 135-142.]). For their detonation properties, see: Keshavarz et al. (2007[Keshavarz, M. H., Pouretedal, H. R. & Semnani, A. (2007). J. Hazard. Mater. 141, 803-807.]); Zaitsev et al. (2009)[Zaitsev, A. A., Dalinger, I. L. & Shaevelev, S. A. (2009). Russ. Chem. Rev. 78, 589-627.]. For the synthesis, see: Katritzky et al. (2005[Katritzky, A. R., Scriven, E. F. V., Majumder, S., Akhmedova, R. G., Akhmedov, N. G. & Vakulenko, A. V. (2005). ARKIVOC, iii, 179-191.]).

[Scheme 1]

Experimental

Crystal data

  • 2C3H2N4O4·0.5C6H6

  • Mr = 355.23

  • Monoclinic, P 21 /n

  • a = 7.4579 (15) Å

  • b = 9.787 (2) Å

  • c = 19.534 (4) Å

  • β = 94.87 (3)°

  • V = 1420.7 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.15 mm−1

  • T = 123 K

  • 0.30 × 0.20 × 0.20 mm
Data collection

  • Rigaku R-AXIS RAPID IP diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.957, Tmax = 0.971

  • 3454 measured reflections

  • 3256 independent reflections

  • 1267 reflections with I > 2σ(I)

  • Rint = 0.084
Refinement

  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.105

  • S = 0.92

  • 3256 reflections

  • 235 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.33 e Å−3

Data collection: RAPID-AUTO (Rigaku, 2000[Rigaku (2000). RAPID-AUTO and CrystalStructure. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku, 2000[Rigaku (2000). RAPID-AUTO and CrystalStructure. Rigaku Corporation, Tokyo, Japan.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811015996/zs2110sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811015996/zs2110Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811015996/zs2110Isup3.cml

checkCIF report


Comment top

Polynitropyrazole systems have been investigated extensively because of their biological activity (Alejandre-Durán et al., 1986; Grigor'ev et al., 1998; Xuan et al., 1999). Recently, these so called "high energy density materials" have attracted renewed attention because of their favorable detonation performance (Keshavarz et al., 2007; Zaitsev et al., 2009). As a potential candidate, 3,4-dinitropyrazole was synthesized by the nitration of pyrazole (Katritzky et al., 2005). Here we report the crystal structure of the title compound, the benzene solvate 4(C3H2N2O4). C6H6 (I).

In the crystal structure of (I) (Fig. 1), the nitro groups are twisted with respect to the pyrazole plane, making dihedral angles of 11.7° (N1/O1, O2), 31.1° (N2/O3, O4) (molecule A) and 21.8° (N5/O5, O6), 25.0° (N6/O7, O8) (molecule B).

Related literature top

For the biological properties of polynitropyrazoles, see: Alejandre-Durán et al. (1986); Grigor'ev et al. (1998); Xuan et al. (1999). For their detonation properties, see: Keshavarz et al. (2007); Zaitsev et al. (2009). For the synthesis, see: Katritzky et al. (2005).

Experimental top

The title compound was prepared by the nitrification of pyrazole according to the literature method (Katritzky et al., 2005). Single crystals suitable for X-ray diffraction were obtained by evaporation of a solution of the compound in benzene at room temperature.

Refinement top

All H atoms were positioned geometrically and treated as riding, with C—H bond lengths constrained to 0.95 Å and Uiso(H) = 1.2Ueq(C), and the N—H bond = 0.87 Å and Uiso(H) = 1.5Ueq(N).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 2000); cell refinement: RAPID-AUTO (Rigaku, 2000); data reduction: CrystalStructure (Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the asymmetric unit of the title compound with the atom numbering scheme. The benzene molecule has inversion symmetry [symmetry code (i): -x + 2, -y, -z]. Hydrogen atoms are omitted and displacement ellipsoids are drawn at the 30% probability level.
3,4-Dinitro-1H-pyrazole benzene 0.25-solvate top
Crystal data top
2C3H2N4O4·0.5C6H6F(000) = 724
Mr = 355.23Dx = 1.661 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3256 reflections
a = 7.4579 (15) Åθ = 2.1–27.5°
b = 9.787 (2) ŵ = 0.15 mm−1
c = 19.534 (4) ÅT = 123 K
β = 94.87 (3)°Block, colorless
V = 1420.7 (5) Å30.30 × 0.20 × 0.20 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID IP
diffractometer		3256 independent reflections
Radiation source: fine-focus sealed tube1267 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.084
Detector resolution: 10.00 pixels mm-1θmax = 27.5°, θmin = 2.1°
ω scansh = −9→9
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		k = −12→12
Tmin = 0.957, Tmax = 0.971l = −25→25
3256 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.060H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.105 w = 1/[σ2(Fo2) + (0.P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.92(Δ/σ)max < 0.001
3256 reflectionsΔρmax = 0.27 e Å−3
235 parametersΔρmin = −0.33 e Å−3
2 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0081 (6)
Crystal data top
2C3H2N4O4·0.5C6H6V = 1420.7 (5) Å3
Mr = 355.23Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.4579 (15) ŵ = 0.15 mm−1
b = 9.787 (2) ÅT = 123 K
c = 19.534 (4) Å0.30 × 0.20 × 0.20 mm
β = 94.87 (3)°
Data collection top
Rigaku R-AXIS RAPID IP
diffractometer		3256 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		1267 reflections with I > 2σ(I)
Tmin = 0.957, Tmax = 0.971Rint = 0.084
3256 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0602 restraints
wR(F2) = 0.105H atoms treated by a mixture of independent and constrained refinement
S = 0.92Δρmax = 0.27 e Å−3
3256 reflectionsΔρmin = −0.33 e Å−3
235 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
C10.9887 (4)0.1907 (3)0.19586 (16)0.0327 (8)
C21.1357 (4)0.1088 (4)0.19047 (17)0.0420 (9)
H21.25850.13590.19530.050*
C30.8410 (4)0.1014 (3)0.18468 (16)0.0289 (8)
C40.5086 (4)0.5510 (3)0.09984 (17)0.0387 (9)
C50.3685 (4)0.6383 (3)0.11466 (16)0.0344 (8)
C60.6606 (4)0.6268 (4)0.10959 (18)0.0538 (11)
H60.78010.59750.10450.065*
C71.1648 (8)0.0615 (7)0.0108 (2)0.0902 (16)
H71.27900.10450.01800.108*
C81.0067 (11)0.1372 (5)0.0150 (2)0.0921 (19)
H81.01320.23180.02580.111*
C90.8469 (8)0.0760 (7)0.0040 (2)0.0880 (17)
H90.73990.12790.00630.106*
N10.9970 (4)0.3361 (3)0.20565 (14)0.0409 (7)
N20.6477 (3)0.1259 (3)0.18791 (15)0.0431 (8)
N31.0721 (3)−0.0172 (3)0.17704 (15)0.0415 (8)
N40.8896 (3)−0.0246 (3)0.17325 (13)0.0364 (7)
N50.5049 (4)0.4072 (3)0.08235 (17)0.0540 (9)
N60.1748 (3)0.6197 (3)0.10954 (15)0.0422 (7)
N70.6079 (4)0.7520 (4)0.12796 (17)0.0533 (9)
N80.4295 (3)0.7621 (3)0.13217 (14)0.0455 (8)
O11.1467 (3)0.3853 (3)0.22096 (13)0.0593 (8)
O20.8580 (3)0.4027 (3)0.19682 (14)0.0638 (8)
O30.6020 (3)0.2140 (3)0.22658 (13)0.0616 (8)
O40.5471 (3)0.0518 (3)0.15166 (14)0.0585 (8)
O50.6340 (4)0.3642 (3)0.05424 (15)0.0840 (10)
O60.3762 (4)0.3390 (3)0.09674 (17)0.0864 (10)
O70.1130 (3)0.5307 (3)0.07052 (13)0.0636 (8)
O80.0861 (3)0.6953 (3)0.14284 (14)0.0631 (8)
H7A0.684 (5)0.820 (4)0.127 (3)0.17 (2)*
H31.138 (3)−0.091 (2)0.1735 (17)0.052 (11)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0275 (18)0.0321 (19)0.038 (2)−0.0016 (15)0.0019 (15)0.0026 (17)
C20.0259 (18)0.042 (2)0.057 (2)0.0014 (17)−0.0032 (16)−0.004 (2)
C30.0226 (16)0.0290 (18)0.0343 (18)0.0030 (14)−0.0015 (14)0.0029 (16)
C40.0326 (19)0.039 (2)0.044 (2)0.0008 (17)−0.0042 (15)−0.001 (2)
C50.0306 (18)0.034 (2)0.038 (2)−0.0019 (16)−0.0017 (14)−0.0027 (18)
C60.0279 (19)0.070 (3)0.063 (3)−0.001 (2)−0.0027 (18)0.013 (3)
C70.112 (5)0.101 (5)0.056 (3)−0.015 (4)−0.007 (3)0.007 (3)
C80.177 (6)0.047 (3)0.047 (3)−0.006 (4)−0.019 (4)−0.001 (3)
C90.127 (5)0.089 (5)0.046 (3)0.043 (4)−0.004 (3)−0.002 (3)
N10.0403 (18)0.0392 (19)0.0422 (18)−0.0050 (15)−0.0027 (14)−0.0002 (16)
N20.0299 (16)0.0406 (19)0.058 (2)−0.0009 (15)−0.0004 (15)0.0044 (18)
N30.0257 (15)0.042 (2)0.056 (2)0.0115 (15)−0.0010 (13)−0.0006 (17)
N40.0232 (14)0.0343 (17)0.0511 (18)0.0016 (12)0.0007 (12)0.0042 (15)
N50.051 (2)0.048 (2)0.061 (2)0.0108 (18)−0.0078 (17)−0.0066 (19)
N60.0311 (16)0.0382 (18)0.056 (2)−0.0012 (15)−0.0003 (14)0.0049 (18)
N70.045 (2)0.049 (2)0.063 (2)−0.0178 (18)−0.0099 (16)0.0041 (19)
N80.0431 (18)0.0332 (18)0.059 (2)−0.0049 (15)−0.0009 (15)−0.0002 (17)
O10.0446 (15)0.0533 (17)0.0775 (19)−0.0211 (14)−0.0100 (13)−0.0038 (16)
O20.0497 (15)0.0403 (16)0.099 (2)0.0119 (13)−0.0072 (15)0.0013 (16)
O30.0338 (14)0.0637 (19)0.089 (2)0.0096 (14)0.0136 (13)−0.0253 (18)
O40.0272 (13)0.0502 (17)0.096 (2)−0.0024 (12)−0.0094 (12)−0.0134 (17)
O50.071 (2)0.078 (2)0.105 (2)0.0246 (17)0.0199 (17)−0.030 (2)
O60.082 (2)0.0369 (18)0.141 (3)−0.0096 (16)0.015 (2)−0.0024 (19)
O70.0371 (14)0.066 (2)0.085 (2)−0.0130 (14)−0.0100 (13)−0.0203 (18)
O80.0405 (15)0.0539 (18)0.098 (2)0.0059 (14)0.0231 (14)−0.0095 (18)
Geometric parameters (Å, º) top
C1—C21.370 (4)C8—C91.335 (7)
C1—C31.409 (4)C8—H80.9500
C1—N11.436 (4)C9—C7i1.377 (7)
C2—N31.339 (4)C9—H90.9500
C2—H20.9500N1—O21.224 (3)
C3—N41.310 (4)N1—O11.229 (3)
C3—N21.468 (3)N2—O31.214 (3)
C4—C61.355 (4)N2—O41.225 (3)
C4—C51.398 (4)N3—N41.359 (3)
C4—N51.448 (4)N3—H30.876 (10)
C5—N81.328 (4)N5—O61.221 (4)
C5—N61.451 (4)N5—O51.223 (4)
C6—N71.344 (4)N6—O81.217 (3)
C6—H60.9500N6—O71.222 (3)
C7—C9i1.377 (7)N7—N81.344 (4)
C7—C81.401 (7)N7—H7A0.878 (10)
C7—H70.9500
C2—C1—C3104.2 (3)C8—C9—C7i120.8 (5)
C2—C1—N1124.3 (3)C8—C9—H9119.6
C3—C1—N1131.3 (3)C7i—C9—H9119.6
N3—C2—C1106.3 (3)O2—N1—O1124.5 (3)
N3—C2—H2126.8O2—N1—C1118.8 (3)
C1—C2—H2126.8O1—N1—C1116.6 (3)
N4—C3—C1112.7 (3)O3—N2—O4126.1 (3)
N4—C3—N2116.7 (3)O3—N2—C3118.1 (3)
C1—C3—N2130.5 (3)O4—N2—C3115.7 (3)
C6—C4—C5105.5 (3)C2—N3—N4113.3 (3)
C6—C4—N5124.4 (3)C2—N3—H3125 (2)
C5—C4—N5130.0 (3)N4—N3—H3121 (2)
N8—C5—C4111.4 (3)C3—N4—N3103.4 (3)
N8—C5—N6116.7 (3)O6—N5—O5125.4 (3)
C4—C5—N6131.7 (3)O6—N5—C4118.5 (3)
N7—C6—C4106.1 (3)O5—N5—C4116.1 (3)
N7—C6—H6127.0O8—N6—O7125.0 (3)
C4—C6—H6127.0O8—N6—C5118.0 (3)
C9i—C7—C8119.4 (5)O7—N6—C5117.0 (3)
C9i—C7—H7120.3N8—N7—C6113.4 (3)
C8—C7—H7120.3N8—N7—H7A126 (3)
C9—C8—C7119.8 (5)C6—N7—H7A119 (3)
C9—C8—H8120.1C5—N8—N7103.7 (3)
C7—C8—H8120.1
C3—C1—C2—N30.1 (4)C1—C3—N2—O3−29.0 (5)
N1—C1—C2—N3−175.8 (3)N4—C3—N2—O4−31.6 (4)
C2—C1—C3—N4−0.1 (4)C1—C3—N2—O4152.5 (3)
N1—C1—C3—N4175.4 (3)C1—C2—N3—N4−0.1 (4)
C2—C1—C3—N2175.9 (3)C1—C3—N4—N30.0 (4)
N1—C1—C3—N2−8.6 (6)N2—C3—N4—N3−176.6 (3)
C6—C4—C5—N80.5 (4)C2—N3—N4—C30.1 (4)
N5—C4—C5—N8176.4 (4)C6—C4—N5—O6155.9 (4)
C6—C4—C5—N6175.6 (3)C5—C4—N5—O6−19.3 (6)
N5—C4—C5—N6−8.5 (6)C6—C4—N5—O5−23.7 (5)
C5—C4—C6—N7−1.0 (4)C5—C4—N5—O5161.0 (3)
N5—C4—C6—N7−177.2 (3)N8—C5—N6—O8−25.2 (4)
C9i—C7—C8—C9−0.8 (8)C4—C5—N6—O8159.9 (3)
C7—C8—C9—C7i0.8 (9)N8—C5—N6—O7153.1 (3)
C2—C1—N1—O2166.3 (3)C4—C5—N6—O7−21.8 (5)
C3—C1—N1—O2−8.5 (6)C4—C6—N7—N81.2 (4)
C2—C1—N1—O1−12.0 (5)C4—C5—N8—N70.3 (4)
C3—C1—N1—O1173.2 (3)N6—C5—N8—N7−175.7 (3)
N4—C3—N2—O3146.8 (3)C6—N7—N8—C5−0.9 (4)
Symmetry code: (i) −x+2, −y, −z.

Experimental details

Crystal data
Chemical formula2C3H2N4O4·0.5C6H6
Mr355.23
Crystal system, space groupMonoclinic, P21/n
Temperature (K)123
a, b, c (Å)7.4579 (15), 9.787 (2), 19.534 (4)
β (°) 94.87 (3)
V (Å3)1420.7 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.15
Crystal size (mm)0.30 × 0.20 × 0.20
Data collection
DiffractometerRigaku R-AXIS RAPID IP
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.957, 0.971
No. of measured, independent and
observed [I > 2σ(I)] reflections		3256, 3256, 1267
Rint0.084
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.105, 0.92
No. of reflections3256
No. of parameters235
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.27, −0.33

Computer programs: RAPID-AUTO (Rigaku, 2000), CrystalStructure (Rigaku, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

The authors thank the China North Industries Group Corporation for financial support.

References

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 6| June 2011| Page o1369
doi:10.1107/S1600536811015996
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