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Acta Crystallogr Sect E Struct Rep Online. 2009 February 1; 65(Pt 2): o275–o276.
Published online 2009 January 10. doi:  10.1107/S1600536809000488
PMCID: PMC2968147

Ethyl 5-amino-1-(4-chloro-2-nitro­phen­yl)-1H-pyrazole-4-carboxyl­ate

Abstract

In the mol­ecule of the title compound, C12H11ClN4O4, the pyrazole ring is coplanar with the amino and ethoxy­carbonyl groups within 0.026 (2) and 0.105 (2) Å, respectively. The C 6 ring of the 4-chloro-2-nitro­phenyl group is twisted by 53.58 (4)° relative to the plane of the pyrazole ring. The planar structure of the pyrazole ring is stabilized by an intra­molecular N—H(...)O hydrogen bond between its substituents. Neighbouring mol­ecules are linked through inter­molecular N—H(...)N and N—H(...)O hydrogen bonds, giving rise to one-dimensional tapes along the b axis. Mol­ecules in the chain are linked to those of an adjacent chain through weak C—H(...)O inter­actions, forming a three-dimensional network.

Related literature

For the biological activity of pyrazole and its derivatives, see: Iovu et al. (2003 [triangle]); Mahajan et al. (1991 [triangle]); related literature, see: Akhtar et al. (2008 [triangle]); Baraldi et al. (1998 [triangle]); Bruno et al. (1990 [triangle]); Cottineau et al. (2002 [triangle]); Smith et al. (2001 [triangle]). For the use of pyrazole-based ligands in investigating the structure–activity relationship of the active site of metalloproteins, see: Dardari et al. (2006 [triangle]), and in the preparation of commercially important dyestuffs, see: Baroni & Kovyrzina (1961 [triangle]); Neunhoeffer et al. (1959 [triangle]). For the synthesis and biological evaluation of heterocyclic compounds, see: Akhtar et al. (2008 [triangle]); Zia-ur-Rehman et al. (2006 [triangle], 2008 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0o275-scheme1.jpg

Experimental

Crystal data

  • C12H11ClN4O4
  • M r = 310.70
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0o275-efi4.jpg
  • a = 8.5899 (8) Å
  • b = 10.2413 (9) Å
  • c = 15.6633 (14) Å
  • β = 96.5415 (13)°
  • V = 1369.0 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.30 mm−1
  • T = 150 (2) K
  • 0.79 × 0.27 × 0.09 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2007 [triangle]) T min = 0.797, T max = 0.973
  • 15944 measured reflections
  • 4189 independent reflections
  • 3588 reflections with I > 2σ(I)
  • R int = 0.022

Refinement

  • R[F 2 > 2σ(F 2)] = 0.034
  • wR(F 2) = 0.096
  • S = 1.04
  • 4189 reflections
  • 197 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.44 e Å−3
  • Δρmin = −0.27 e Å−3

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL and local programs.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809000488/bt2841sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809000488/bt2841Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors are grateful to the Pakistan Council of Scientific & Industrial Research Laboratories, Lahore, Pakistan, for the provision of necessary chemicals.

supplementary crystallographic information

Comment

Pyrazole and its derivatives represent one of the most important classes of organic heterocyclic compounds, possessing a wide spectrum of biological activities such as antibacterial, fungicidal (Iovu et al., 2003), herbicidal (Mahajan et al.,1991) and antiviral (Baraldi et al., 1998) activities. Some of their derivatives have been reported to possess significant antiarrhythmic & sedative (Bruno et al., 1990), hypoglycemic (Cottineau et al., 2002) and anti-inflammatory (Smith et al., 2001) activities. In addition, pyrazole based ligands have also been used to investigate the structure-activity relationship of the active site of metalloproteins (Dardari et al., 2006) and for the preparation of commercially important dyestuffs (Baroni & Kovyrzina, 1961; Neunhoeffer et al.,1959). As part of our ongoing research on the synthesis and biological evaluation of heterocyclic compounds (Akhtar et al., 2008; Zia-ur-Rehman et al., 2006; Zia-ur-Rehman et al., 2008), crystal structure of the title compound, (I) was determined.

In I (Fig. 1) the pyrazole ring is approximately coplanar with the amino and ethyl carboxylate groups. The C6 ring of the 4-chloro-2-nitro phenyl group is essentially planar and is twisted by 53.58 (4)° relative to the plane of the pyrazole ring about the C6—N2 bond. The planar structure of the pyrazole ring is stabilized by an intramolecular N—H···O hydrogen bond between the amino and ethyl carboxylate substituents (Table 1). Neighbouring molecules are linked through one N—H···N and one N—H···O intermolecular hydrogen bond giving rise to one-dimensional tapes along the b axis (Fig. 2, Table 1). The nitro group is twisted by 37.98 (4)° relative to the C6 ring, driven by the desire to form the aforementioned H-bond. Each chain is cross-linked to the next through weak C–H···O interactions.

Experimental

A mixture of 5-amino-1-(4-chloro-2-nitrophenyl)-1H-pyrazole-4-carboxylic acid (3.05 g; 10.0 mmoles), phosphoric acid (0.196 g; 2.0 mmoles) and ethyl alcohol (100 ml) was refluxed for a period of five hours. The reaction mixture was then concentrated (to a volume of 20 ml) by slow distillation of ethanol followed by cooling and addition of cold water. The precipitated solid was then filtered, washed with cold water and dried. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a solution of the title compound in a mixture of ethanol and water (85: 15); yield: 73.68%.

Refinement

H atoms bound to C were placed in geometric positions (C—H distance = 0.95 Å) using a riding model. H atoms on N had coordinates freely refined. Uiso values were set to 1.2Ueq (1.5Ueq for CH3).

Figures

Fig. 1.
The asymmetric unit of the title compound highlighting the intramolecular H-bond. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
Perspective view of the crystal packing showing hydrogen-bond interactions (dashed lines). H atoms not involved in hydrogen bonding have been omitted for clarity. Symmetry operator i = -x + 1/2, y - 1/2, -z + 3/2.

Crystal data

C12H11ClN4O4F(000) = 640
Mr = 310.70Dx = 1.508 Mg m3
Monoclinic, P21/nMelting point: 435 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.5899 (8) ÅCell parameters from 6502 reflections
b = 10.2413 (9) Åθ = 2.6–30.6°
c = 15.6633 (14) ŵ = 0.30 mm1
β = 96.5415 (13)°T = 150 K
V = 1369.0 (2) Å3Lath, colourless
Z = 40.79 × 0.27 × 0.09 mm

Data collection

Bruker APEXII CCD diffractometer4189 independent reflections
Radiation source: fine-focus sealed tube3588 reflections with I > 2σ(I)
graphiteRint = 0.022
ω rotation with narrow frames scansθmax = 30.6°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)h = −12→12
Tmin = 0.797, Tmax = 0.973k = −14→14
15944 measured reflectionsl = −22→22

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: all non-H atoms found by direct methods
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: geom except NH coords freely refined
wR(F2) = 0.096H atoms treated by a mixture of independent and constrained refinement
S = 1.04w = 1/[σ2(Fo2) + (0.0507P)2 + 0.3692P] where P = (Fo2 + 2Fc2)/3
4189 reflections(Δ/σ)max = 0.001
197 parametersΔρmax = 0.44 e Å3
0 restraintsΔρmin = −0.27 e Å3

Special details

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)

xyzUiso*/Ueq
C10.16661 (12)0.37722 (10)0.87165 (6)0.01863 (19)
N10.00154 (11)0.39144 (9)0.83571 (6)0.02209 (18)
O1−0.04727 (11)0.32020 (9)0.77617 (6)0.0316 (2)
O2−0.07682 (10)0.47313 (9)0.86871 (6)0.03110 (19)
C20.19621 (13)0.36020 (11)0.95971 (7)0.0216 (2)
H20.11350.36090.99510.026*
C30.35046 (14)0.34216 (10)0.99458 (7)0.0224 (2)
Cl10.39123 (4)0.31052 (3)1.103127 (17)0.03302 (9)
C40.47238 (13)0.34677 (11)0.94341 (7)0.0229 (2)
H40.57770.33700.96850.028*
C50.43941 (13)0.36565 (10)0.85546 (7)0.0218 (2)
H50.52270.36910.82050.026*
C60.28554 (12)0.37949 (10)0.81810 (6)0.01836 (19)
N20.25381 (11)0.40263 (9)0.72882 (5)0.01940 (17)
N30.16947 (11)0.51311 (9)0.69958 (6)0.02197 (19)
C70.17042 (12)0.51027 (10)0.61560 (7)0.0206 (2)
H70.12150.57440.57780.025*
C80.25215 (12)0.40156 (10)0.58811 (6)0.01772 (19)
C90.30396 (12)0.33322 (10)0.66310 (6)0.01755 (19)
N40.39081 (12)0.22356 (9)0.67437 (6)0.0241 (2)
H4A0.4077 (18)0.1853 (14)0.6270 (11)0.029*
H4B0.3806 (18)0.1713 (14)0.7173 (10)0.029*
C100.28074 (12)0.36124 (10)0.50279 (6)0.01900 (19)
O30.35936 (10)0.26670 (8)0.48774 (5)0.02577 (17)
O40.20696 (9)0.43861 (8)0.44194 (5)0.02405 (17)
C110.23017 (13)0.40996 (12)0.35329 (7)0.0250 (2)
H11A0.13770.43960.31460.030*
H11B0.24070.31450.34600.030*
C120.37412 (17)0.47691 (14)0.32935 (9)0.0355 (3)
H12A0.36550.57110.33890.053*
H12B0.38450.46050.26860.053*
H12C0.46650.44290.36490.053*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0220 (5)0.0179 (4)0.0160 (4)0.0002 (4)0.0023 (4)−0.0002 (3)
N10.0232 (4)0.0248 (4)0.0183 (4)−0.0023 (3)0.0024 (3)0.0032 (3)
O10.0339 (5)0.0367 (5)0.0230 (4)−0.0084 (4)−0.0021 (3)−0.0042 (3)
O20.0271 (4)0.0339 (5)0.0330 (5)0.0062 (3)0.0063 (3)−0.0003 (4)
C20.0273 (5)0.0227 (5)0.0153 (4)−0.0007 (4)0.0047 (4)−0.0004 (4)
C30.0319 (5)0.0202 (5)0.0146 (4)0.0005 (4)0.0007 (4)−0.0002 (4)
Cl10.04426 (18)0.03893 (17)0.01462 (13)0.00482 (13)−0.00204 (11)0.00275 (10)
C40.0253 (5)0.0213 (5)0.0213 (5)0.0024 (4)−0.0011 (4)0.0009 (4)
C50.0243 (5)0.0208 (5)0.0209 (5)0.0029 (4)0.0054 (4)0.0020 (4)
C60.0256 (5)0.0164 (4)0.0134 (4)0.0016 (4)0.0035 (4)0.0008 (3)
N20.0258 (4)0.0188 (4)0.0142 (4)0.0057 (3)0.0046 (3)0.0019 (3)
N30.0291 (4)0.0192 (4)0.0179 (4)0.0085 (3)0.0044 (3)0.0019 (3)
C70.0237 (5)0.0207 (5)0.0174 (4)0.0043 (4)0.0030 (4)0.0022 (4)
C80.0202 (4)0.0185 (4)0.0149 (4)0.0013 (3)0.0038 (3)0.0015 (3)
C90.0205 (4)0.0171 (4)0.0156 (4)0.0007 (3)0.0048 (3)0.0004 (3)
N40.0361 (5)0.0188 (4)0.0187 (4)0.0091 (4)0.0090 (4)0.0037 (3)
C100.0193 (4)0.0223 (5)0.0157 (4)−0.0012 (4)0.0028 (3)0.0010 (4)
O30.0318 (4)0.0266 (4)0.0196 (4)0.0076 (3)0.0058 (3)−0.0015 (3)
O40.0266 (4)0.0313 (4)0.0145 (3)0.0064 (3)0.0031 (3)0.0029 (3)
C110.0238 (5)0.0369 (6)0.0141 (4)−0.0005 (4)0.0019 (4)0.0012 (4)
C120.0395 (7)0.0374 (7)0.0321 (6)−0.0095 (6)0.0150 (5)0.0001 (5)

Geometric parameters (Å, °)

C1—C21.3848 (14)C7—C81.4096 (14)
C1—C61.3940 (14)C7—H70.9500
C1—N11.4719 (14)C8—C91.3958 (14)
N1—O11.2202 (13)C8—C101.4462 (14)
N1—O21.2245 (13)C9—N41.3487 (13)
C2—C31.3868 (16)N4—H4A0.866 (16)
C2—H20.9500N4—H4B0.871 (15)
C3—C41.3902 (16)C10—O31.2188 (13)
C3—Cl11.7271 (11)C10—O41.3418 (12)
C4—C51.3881 (15)O4—C111.4549 (13)
C4—H40.9500C11—C121.4985 (17)
C5—C61.3904 (15)C11—H11A0.9900
C5—H50.9500C11—H11B0.9900
C6—N21.4140 (12)C12—H12A0.9800
N2—C91.3607 (13)C12—H12B0.9800
N2—N31.3925 (12)C12—H12C0.9800
N3—C71.3166 (13)
C2—C1—C6122.51 (10)C8—C7—H7123.8
C2—C1—N1116.93 (9)C9—C8—C7105.13 (9)
C6—C1—N1120.55 (9)C9—C8—C10124.27 (9)
O1—N1—O2125.00 (10)C7—C8—C10130.60 (9)
O1—N1—C1117.73 (9)N4—C9—N2123.64 (9)
O2—N1—C1117.26 (9)N4—C9—C8130.26 (9)
C1—C2—C3117.89 (10)N2—C9—C8106.06 (9)
C1—C2—H2121.1C9—N4—H4A114.1 (10)
C3—C2—H2121.1C9—N4—H4B120.7 (10)
C2—C3—C4121.15 (10)H4A—N4—H4B115.1 (14)
C2—C3—Cl1119.35 (9)O3—C10—O4123.99 (9)
C4—C3—Cl1119.49 (9)O3—C10—C8124.18 (9)
C5—C4—C3119.67 (10)O4—C10—C8111.82 (9)
C5—C4—H4120.2C10—O4—C11116.99 (9)
C3—C4—H4120.2O4—C11—C12110.69 (10)
C4—C5—C6120.57 (10)O4—C11—H11A109.5
C4—C5—H5119.7C12—C11—H11A109.5
C6—C5—H5119.7O4—C11—H11B109.5
C5—C6—C1118.15 (9)C12—C11—H11B109.5
C5—C6—N2120.01 (9)H11A—C11—H11B108.1
C1—C6—N2121.74 (9)C11—C12—H12A109.5
C9—N2—N3111.92 (8)C11—C12—H12B109.5
C9—N2—C6128.23 (9)H12A—C12—H12B109.5
N3—N2—C6119.72 (8)C11—C12—H12C109.5
C7—N3—N2104.38 (8)H12A—C12—H12C109.5
N3—C7—C8112.50 (9)H12B—C12—H12C109.5
N3—C7—H7123.8
C2—C1—N1—O1−127.78 (11)C9—N2—N3—C7−0.53 (12)
C6—C1—N1—O151.47 (14)C6—N2—N3—C7175.66 (9)
C2—C1—N1—O251.39 (13)N2—N3—C7—C80.14 (12)
C6—C1—N1—O2−129.37 (11)N3—C7—C8—C90.27 (12)
C6—C1—C2—C3−1.37 (16)N3—C7—C8—C10179.76 (10)
N1—C1—C2—C3177.85 (9)N3—N2—C9—N4178.62 (10)
C1—C2—C3—C42.81 (16)C6—N2—C9—N42.83 (17)
C1—C2—C3—Cl1−176.02 (8)N3—N2—C9—C80.70 (12)
C2—C3—C4—C5−2.04 (17)C6—N2—C9—C8−175.09 (10)
Cl1—C3—C4—C5176.78 (8)C7—C8—C9—N4−178.30 (11)
C3—C4—C5—C6−0.24 (16)C10—C8—C9—N42.17 (18)
C4—C5—C6—C11.62 (16)C7—C8—C9—N2−0.57 (11)
C4—C5—C6—N2178.08 (10)C10—C8—C9—N2179.90 (10)
C2—C1—C6—C5−0.81 (16)C9—C8—C10—O3−3.61 (17)
N1—C1—C6—C5179.99 (9)C7—C8—C10—O3176.99 (11)
C2—C1—C6—N2−177.21 (10)C9—C8—C10—O4174.82 (10)
N1—C1—C6—N23.59 (15)C7—C8—C10—O4−4.59 (16)
C5—C6—N2—C952.72 (15)O3—C10—O4—C11−3.17 (15)
C1—C6—N2—C9−130.95 (11)C8—C10—O4—C11178.40 (9)
C5—C6—N2—N3−122.79 (11)C10—O4—C11—C12−86.64 (13)
C1—C6—N2—N353.54 (14)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N4—H4A···O30.866 (16)2.328 (16)2.9383 (13)127.7 (12)
N4—H4A···O2i0.866 (16)2.610 (15)3.1356 (13)120.1 (12)
N4—H4B···N3i0.871 (15)2.153 (16)3.0074 (13)166.8 (14)

Symmetry codes: (i) −x+1/2, y−1/2, −z+3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2841).

References

  • Akhtar, T., Hameed, S., Zia-ur-Rehman, M., Hussain Bukhari, T. & Khan, I. (2008). Acta Cryst. E64, o1388. [PMC free article] [PubMed]
  • Baraldi, P. G., Manfredini, S., Romagnoli, R., Stevanato, L., Zaid, A. N. & Manservigi, R. (1998). Nucleosides Nucleotides, 17, 2165–2171.
  • Baroni, E. E. & Kovyrzina, K. A. (1961). Zh. Obshch. Khim.31, 1641–1645.
  • Bruker (2006). APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.
  • Bruno, O., Bondavalli, F., Ranise, A., Schenone, P., Losasso, C., Cilenti, L., Matera, C. & Marmo, E. (1990). Farmaco, 45, 147–66. [PubMed]
  • Cottineau, B., Toto, P., Marot, C., Pipaud, A. & Chenault, J. (2002). Bioorg. Med. Chem.12, 2105–2108. [PubMed]
  • Dardari, Z., Lemrani, M., Sebban, A., Bahloul, A., Hassair, M., Kitane, S., Berrada, M. & Boudouma, M. (2006). Arch. Pharm.339, 291–298. [PubMed]
  • Iovu, M., Zalaru, C., Dumitrascu, F., Draghici, C., Moraru, M. & Criste, E. (2003). Farmaco, 58, 301–307. [PubMed]
  • Mahajan, R. N., Havaldar, F. H. & Fernandes, P. S. (1991). J. Indian Chem. Soc.68, 245–249.
  • Neunhoeffer, O., Alsdorf, G. & Ulrich, H. (1959). Chem. Ber.92, 252–256.
  • Sheldrick, G. M. (2007). SADABS University of Göttingen, Germany.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Smith, S. R., Denhardt, G. & Terminelli, C. (2001). Eur. J. Pharmacol.432, 107–119. [PubMed]
  • Zia-ur-Rehman, M., Choudary, J. A., Ahmad, S. & Siddiqui, H. L. (2006). Chem. Pharm. Bull.54, 1175–1178. [PubMed]
  • Zia-ur-Rehman, M., Elsegood, M. R. J., Akbar, N. & Shah Zaib Saleem, R. (2008). Acta Cryst. E64, o1312–o1313. [PMC free article] [PubMed]

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