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ISSN: 2056-9890

2-Chloro-N-{3-cyano-1-[2,6-di­chloro-4-(tri­fluoro­meth­yl)phen­yl]-1H-pyrazol-5-yl}acetamide

aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing, Nanjing 210009, People's Republic of China
*Correspondence e-mail: rwan@njut.edu.cn

(Received 27 October 2011; accepted 7 December 2011; online 14 December 2011)

The title compound, C13H6Cl3F3N4O, was synthesized by the reaction of 5-amino-1-[2,6-dichloro-4-(trifluoro­meth­yl)phen­yl]-1H-pyrazole-3-carbonitrile and 2-chloro­acetyl chloride. The five-membered pyrazole ring makes a dihedral angle of 71.5 (3)° with the benzene ring. The –CF3 group is disordered by rotation, and the F atoms are split over two sets of sites with occupancies of 0.59 (2) and 0.41 (2). The crystal structure features weak C—H⋯O and N—H⋯N inter­actions involving the carbonyl and cyano groups as acceptors.

Related literature

For biological properties of N-pyrazole derivatives, see: Cheng et al. (2008[Cheng, J. L., Wei, F. L., Zhu, L., Zhao, J. H. & Zhu, G. N. (2008). Chin. J. Org. Chem. 28, 622-627.]); Liu et al. (2010[Liu, Y. Y., Shi, H., Li, Y. F. & Zhu, H. J. (2010). J. Heterocycl. Chem. 47, 897-902.]); Hatton et al. (1993[Hatton, L. R., Buntain, I. G., Hawkins, D. W., Parnell, E. W. & Pearson, C. J. (1993). US Patent 5232940.]). For related structures, see: Yang et al. (2004[Yang, Z., Zhong, P. & Guo, S. (2004). Acta Cryst. E60, o1277-o1278.]); Zhang et al. (2005[Zhang, X.-H., Chen, J.-Z., Zhong, P., Xiao, H.-P. & Hu, M.-L. (2005). Acta Cryst. E61, o3676-o3678.]); Zhong et al. (2004[Zhong, P., Yang, Z., Li, S. & Tang, R. (2004). Acta Cryst. E60, o2395-o2396.]).

[Scheme 1]

Experimental

Crystal data
  • C13H6Cl3F3N4O

  • Mr = 397.57

  • Triclinic, [P \overline 1]

  • a = 8.4190 (17) Å

  • b = 9.2650 (19) Å

  • c = 11.944 (2) Å

  • α = 69.77 (3)°

  • β = 76.74 (3)°

  • γ = 66.10 (3)°

  • V = 794.9 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.62 mm−1

  • T = 293 K

  • 0.30 × 0.20 × 0.20 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.837, Tmax = 0.887

  • 3133 measured reflections

  • 2921 independent reflections

  • 2313 reflections with I > 2σ(I)

  • Rint = 0.030

  • 3 standard reflections every 200 reflections intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.155

  • S = 1.01

  • 2921 reflections

  • 246 parameters

  • H-atom parameters constrained

  • Δρmax = 0.60 e Å−3

  • Δρmin = −0.58 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N4—H4A⋯N3i 0.86 2.49 3.280 (5) 153
C4—H4B⋯Oii 0.93 2.53 3.349 (5) 148
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z.

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); 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


Comment top

In a variety of biological heterocyclic compounds, N-pyrazole derivatives are of great interest because of their chemical and pharmaceutical properties (Cheng et al., 2008). Some X-ray structures of N-pyrazole compounds have already been reported (Zhang et al., 2005; Zhong et al., 2004; Yang et al., 2004), and they have been found to exhibit good insecticidal activities against diamond-back moth, mustard beetle, vetch aphid and so on (Hatton et al., 1993). Besides, some other N-pyrazole derivatives are known to have antifungal activities (Liu et al., 2010). Herein we report the crystal structure of a new derivative (Fig. 1). In this structure, the pyrazole ring N1/N2/C8/C9/C10 is a planar five-membered ring and the mean deviation from plane is 0.0063 Å. The dihedral angle between the pyrazole and benzene rings is 71.5 (3)°. In the crystal structure, weak intermolecular C—H···O and N—H···N hydrogen bonds (Table 1) link symmetry-related molecules, to form a trimeric unit (Fig. 2), which may be effective in the stabilization of the crystal.

Related literature top

For biological properties of N-pyrazole derivatives, see: Cheng et al. (2008); Liu et al. (2010); Hatton et al. (1993). For related structures, see: Yang et al. (2004); Zhang et al. (2005); Zhong et al. (2004).

Experimental top

To a stirred solution of 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-1H-pyrazole-3-carbonitrile (5 mmol) in THF (20 ml) was added 2-chloroacetyl chloride (5 mmol) dropwise at 0–5 °C. After the addition, the reaction mixture was allowed to rise to room temperature and was stirred for 2 h. The crude product precipitated and was filtered. Pure compound was obtained by crystallization from ethanol. Crystals suitable for X-ray diffraction were obtained by slow evaporation of an acetone solution.

Refinement top

All H atoms bonded to the C atoms were placed geometrically at the distances of 0.93–0.97 Å and included in the refinement in riding motion approximation with Uiso(H) = 1.2 or 1.5Ueq of the carrier atom. F atoms were disordered over two sites, occupancies were refined and converged to 0.565 (12) and 0.435 (12), respectively.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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. A view of the molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Partial packing view showing the hydrogen-bonded network. Dashed lines indicate intermolecular N—H···N and C—H···O hydrogen bonds.
2-Chloro-N-{3-cyano-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]- 1H-pyrazol-5-yl}acetamide top
Crystal data top
C13H6Cl3F3N4OZ = 2
Mr = 397.57F(000) = 396
Triclinic, P1Dx = 1.661 Mg m3
Hall symbol: -P 1Melting point: 483 K
a = 8.4190 (17) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.2650 (19) ÅCell parameters from 25 reflections
c = 11.944 (2) Åθ = 9–13°
α = 69.77 (3)°µ = 0.62 mm1
β = 76.74 (3)°T = 293 K
γ = 66.10 (3)°Block, colourless
V = 794.9 (3) Å30.30 × 0.20 × 0.20 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
2313 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.030
Graphite monochromatorθmax = 25.4°, θmin = 1.8°
ω/2θ scansh = 010
Absorption correction: ψ scan
(North et al., 1968)
k = 1011
Tmin = 0.837, Tmax = 0.887l = 1414
3133 measured reflections3 standard reflections every 200 reflections
2921 independent reflections intensity decay: 1%
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)] = 0.053H-atom parameters constrained
wR(F2) = 0.155 w = 1/[σ2(Fo2) + (0.1P)2 + 0.320P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
2921 reflectionsΔρmax = 0.60 e Å3
246 parametersΔρmin = 0.58 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.195 (13)
Crystal data top
C13H6Cl3F3N4Oγ = 66.10 (3)°
Mr = 397.57V = 794.9 (3) Å3
Triclinic, P1Z = 2
a = 8.4190 (17) ÅMo Kα radiation
b = 9.2650 (19) ŵ = 0.62 mm1
c = 11.944 (2) ÅT = 293 K
α = 69.77 (3)°0.30 × 0.20 × 0.20 mm
β = 76.74 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
2313 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.030
Tmin = 0.837, Tmax = 0.8873 standard reflections every 200 reflections
3133 measured reflections intensity decay: 1%
2921 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0530 restraints
wR(F2) = 0.155H-atom parameters constrained
S = 1.01Δρmax = 0.60 e Å3
2921 reflectionsΔρmin = 0.58 e Å3
246 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O0.3070 (3)0.0918 (3)0.0994 (3)0.0713 (8)
Cl10.20070 (11)0.26994 (9)0.46773 (7)0.0529 (3)
Cl20.04187 (13)0.81751 (11)0.09593 (7)0.0636 (3)
Cl30.66610 (14)0.09291 (16)0.24189 (12)0.0861 (4)
N10.0425 (3)0.4846 (3)0.2382 (2)0.0414 (6)
C10.1882 (4)0.4703 (3)0.3992 (3)0.0380 (6)
N20.1343 (3)0.5475 (3)0.2373 (2)0.0462 (6)
C20.2458 (4)0.5460 (4)0.4546 (3)0.0444 (7)
H2B0.29100.48940.52820.053*
C30.2352 (4)0.7066 (4)0.3993 (3)0.0480 (7)
N30.4748 (4)0.5210 (5)0.1439 (4)0.0816 (11)
N40.3004 (3)0.2913 (4)0.1692 (3)0.0510 (7)
H4A0.36250.33170.18840.061*
C40.1707 (4)0.7917 (4)0.2891 (3)0.0482 (7)
H4B0.16570.89960.25200.058*
C50.1144 (4)0.7150 (4)0.2353 (3)0.0431 (7)
C60.1175 (3)0.5552 (3)0.2906 (2)0.0371 (6)
C70.2921 (6)0.7937 (5)0.4592 (5)0.0759 (12)
C80.1616 (4)0.4631 (4)0.1792 (3)0.0468 (7)
C90.0098 (4)0.3489 (4)0.1413 (3)0.0504 (8)
H9A0.00110.27640.09980.060*
C100.1202 (4)0.3680 (4)0.1793 (3)0.0419 (7)
C110.3373 (5)0.4970 (5)0.1602 (3)0.0597 (9)
C120.3826 (4)0.1554 (4)0.1304 (3)0.0511 (8)
C130.5789 (5)0.0841 (6)0.1261 (4)0.0791 (13)
H13A0.62680.14190.05030.095*
H13B0.61780.03020.12710.095*
F10.193 (2)0.9401 (14)0.447 (3)0.155 (10)0.59 (2)
F20.4449 (12)0.8100 (17)0.3936 (8)0.104 (3)0.59 (2)
F30.3470 (18)0.7085 (13)0.5612 (6)0.111 (4)0.59 (2)
F1'0.1496 (12)0.851 (3)0.5471 (17)0.111 (6)0.41 (2)
F2'0.327 (6)0.913 (4)0.4027 (11)0.169 (13)0.41 (2)
F3'0.3932 (17)0.6929 (17)0.5431 (17)0.135 (8)0.41 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O0.0581 (15)0.0791 (18)0.097 (2)0.0240 (13)0.0006 (14)0.0539 (16)
Cl10.0595 (5)0.0366 (4)0.0579 (5)0.0150 (3)0.0143 (4)0.0052 (3)
Cl20.0760 (6)0.0575 (5)0.0474 (5)0.0184 (4)0.0215 (4)0.0000 (4)
Cl30.0623 (6)0.0942 (8)0.1011 (8)0.0006 (5)0.0307 (6)0.0455 (7)
N10.0354 (13)0.0464 (14)0.0460 (13)0.0133 (11)0.0082 (10)0.0167 (11)
C10.0340 (14)0.0352 (14)0.0432 (15)0.0093 (11)0.0075 (11)0.0105 (12)
N20.0336 (13)0.0546 (15)0.0508 (15)0.0133 (11)0.0082 (11)0.0159 (12)
C20.0419 (16)0.0485 (17)0.0454 (16)0.0113 (13)0.0148 (13)0.0157 (13)
C30.0396 (16)0.0499 (18)0.0607 (19)0.0134 (14)0.0091 (14)0.0236 (15)
N30.0492 (19)0.114 (3)0.097 (3)0.0287 (19)0.0217 (17)0.040 (2)
N40.0399 (14)0.0645 (17)0.0633 (17)0.0206 (12)0.0029 (12)0.0346 (14)
C40.0478 (18)0.0361 (15)0.0593 (19)0.0151 (13)0.0093 (14)0.0093 (13)
C50.0390 (15)0.0418 (16)0.0433 (15)0.0090 (12)0.0095 (12)0.0089 (12)
C60.0320 (14)0.0402 (15)0.0407 (15)0.0103 (11)0.0059 (11)0.0150 (12)
C70.075 (3)0.058 (2)0.112 (4)0.018 (2)0.040 (3)0.031 (2)
C80.0410 (17)0.0599 (19)0.0465 (16)0.0212 (14)0.0118 (13)0.0149 (14)
C90.0486 (18)0.063 (2)0.0535 (18)0.0246 (15)0.0079 (14)0.0256 (15)
C100.0407 (16)0.0487 (16)0.0420 (15)0.0174 (13)0.0047 (12)0.0174 (13)
C110.053 (2)0.077 (2)0.058 (2)0.0258 (18)0.0128 (16)0.0231 (18)
C120.0449 (18)0.063 (2)0.0556 (19)0.0200 (16)0.0018 (14)0.0334 (16)
C130.044 (2)0.116 (4)0.095 (3)0.013 (2)0.0016 (19)0.072 (3)
F10.120 (7)0.087 (7)0.31 (3)0.014 (6)0.107 (12)0.124 (12)
F20.106 (6)0.127 (7)0.122 (5)0.082 (5)0.039 (4)0.020 (5)
F30.200 (10)0.138 (7)0.059 (4)0.118 (8)0.023 (4)0.027 (4)
F1'0.075 (5)0.149 (12)0.155 (11)0.020 (6)0.009 (5)0.124 (10)
F2'0.35 (4)0.16 (2)0.100 (7)0.21 (3)0.044 (17)0.007 (11)
F3'0.074 (5)0.128 (9)0.230 (19)0.043 (7)0.106 (8)0.119 (12)
Geometric parameters (Å, º) top
O—C121.205 (4)N4—H4A0.8600
Cl1—C11.720 (3)C4—C51.368 (4)
Cl2—C51.717 (3)C4—H4B0.9300
Cl3—C131.747 (4)C5—C61.390 (4)
N1—C101.353 (4)C7—F2'1.192 (11)
N1—N21.362 (3)C7—F11.249 (8)
N1—C61.420 (4)C7—F31.273 (9)
C1—C21.382 (4)C7—F3'1.304 (13)
C1—C61.387 (4)C7—F21.381 (9)
N2—C81.319 (4)C7—F1'1.454 (11)
C2—C31.378 (5)C8—C91.389 (5)
C2—H2B0.9300C8—C111.437 (4)
C3—C41.383 (5)C9—C101.369 (4)
C3—C71.504 (5)C9—H9A0.9300
N3—C111.137 (5)C12—C131.506 (5)
N4—C121.353 (4)C13—H13A0.9700
N4—C101.387 (4)C13—H13B0.9700
C10—N1—N2111.9 (2)F2'—C7—F1'103.7 (13)
C10—N1—C6130.1 (2)F3'—C7—F1'91.6 (9)
N2—N1—C6117.8 (2)F2'—C7—F3'114.9 (16)
C2—C1—C6120.8 (3)F1—C7—C3112.7 (5)
C2—C1—Cl1119.3 (2)F2—C7—C3106.0 (6)
C6—C1—Cl1119.9 (2)F3—C7—C3115.0 (5)
C8—N2—N1103.3 (2)F1'—C7—C3107.6 (5)
C3—C2—C1119.0 (3)F2'—C7—C3120.9 (7)
C3—C2—H2B120.5F3'—C7—C3113.0 (7)
C1—C2—H2B120.5N2—C8—C9113.8 (3)
C2—C3—C4121.2 (3)N2—C8—C11119.2 (3)
C2—C3—C7120.2 (3)C9—C8—C11127.1 (3)
C4—C3—C7118.6 (3)C10—C9—C8103.8 (3)
C12—N4—C10122.7 (3)C10—C9—H9A128.1
C12—N4—H4A118.6C8—C9—H9A128.1
C10—N4—H4A118.6N1—C10—C9107.2 (3)
C5—C4—C3119.0 (3)N1—C10—N4120.4 (3)
C5—C4—H4B120.5C9—C10—N4132.4 (3)
C3—C4—H4B120.5N3—C11—C8178.4 (4)
C4—C5—C6121.2 (3)O—C12—N4123.4 (3)
C4—C5—Cl2119.2 (2)O—C12—C13120.0 (3)
C6—C5—Cl2119.6 (2)N4—C12—C13116.7 (3)
C1—C6—C5118.7 (3)C12—C13—Cl3115.8 (2)
C1—C6—N1121.4 (3)C12—C13—H13A108.3
C5—C6—N1119.8 (3)Cl3—C13—H13A108.3
F1—C7—F2102.2 (9)C12—C13—H13B108.3
F1—C7—F3118.1 (10)Cl3—C13—H13B108.3
F3—C7—F2100.1 (6)H13A—C13—H13B107.4
C10—N1—N2—C81.6 (3)C4—C3—C7—F139.4 (16)
C6—N1—N2—C8177.3 (3)C2—C3—C7—F30.4 (9)
C6—C1—C2—C31.3 (4)C4—C3—C7—F3178.8 (8)
Cl1—C1—C2—C3179.9 (2)C2—C3—C7—F3'18.7 (11)
C1—C2—C3—C41.0 (5)C4—C3—C7—F3'162.0 (10)
C1—C2—C3—C7178.2 (3)C2—C3—C7—F2109.2 (6)
C2—C3—C4—C50.9 (5)C4—C3—C7—F271.6 (6)
C7—C3—C4—C5178.3 (3)C2—C3—C7—F1'80.8 (11)
C3—C4—C5—C61.4 (5)C4—C3—C7—F1'98.4 (11)
C3—C4—C5—Cl2177.6 (2)N1—N2—C8—C90.6 (4)
C2—C1—C6—C53.5 (4)N1—N2—C8—C11179.8 (3)
Cl1—C1—C6—C5177.8 (2)N2—C8—C9—C100.6 (4)
C2—C1—C6—N1173.9 (2)C11—C8—C9—C10178.6 (3)
Cl1—C1—C6—N14.8 (4)N2—N1—C10—C92.0 (3)
C4—C5—C6—C13.6 (4)C6—N1—C10—C9177.0 (3)
Cl2—C5—C6—C1175.4 (2)N2—N1—C10—N4179.1 (3)
C4—C5—C6—N1173.8 (3)C6—N1—C10—N44.0 (5)
Cl2—C5—C6—N17.1 (4)C8—C9—C10—N11.5 (4)
C10—N1—C6—C176.2 (4)C8—C9—C10—N4179.8 (3)
N2—N1—C6—C1109.0 (3)C12—N4—C10—N1168.1 (3)
C10—N1—C6—C5106.4 (4)C12—N4—C10—C910.5 (6)
N2—N1—C6—C568.3 (3)C10—N4—C12—O1.4 (6)
C2—C3—C7—F2'161 (3)C10—N4—C12—C13179.0 (3)
C4—C3—C7—F2'20 (3)O—C12—C13—Cl3143.6 (4)
C2—C3—C7—F1139.8 (16)N4—C12—C13—Cl336.7 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N3i0.862.493.280 (5)153
C4—H4B···Oii0.932.533.349 (5)148
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC13H6Cl3F3N4O
Mr397.57
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)8.4190 (17), 9.2650 (19), 11.944 (2)
α, β, γ (°)69.77 (3), 76.74 (3), 66.10 (3)
V3)794.9 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.62
Crystal size (mm)0.30 × 0.20 × 0.20
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.837, 0.887
No. of measured, independent and
observed [I > 2σ(I)] reflections
3133, 2921, 2313
Rint0.030
(sin θ/λ)max1)0.603
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.155, 1.01
No. of reflections2921
No. of parameters246
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.60, 0.58

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N3i0.86002.49003.280 (5)153.00
C4—H4B···Oii0.93002.53003.349 (5)148.00
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z.
 

Acknowledgements

The authors thank Professor Hua-qin Wang of the Analysis Centre, Nanjing University, for providing help during the X-ray crystallographic analysis.

References

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