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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 7| July 2008| Pages o1312-o1313

5-Amino-1-phenyl-1H-pyrazole-4-carboxylic acid

aApplied Chemistry Research Centre, PCSIR Laboratories Complex, Lahore 54600, Pakistan, bChemistry Department, Loughborough University, Loughborough LE11 3TU, England, cCentre for High Energy Physics, University of the Punjab, Lahore 54590, Pakistan, and dDepartment of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
*Correspondence e-mail: rehman_pcsir@hotmail.com

(Received 5 June 2008; accepted 17 June 2008; online 21 June 2008)

In the mol­ecule of the title compound, C10H9N3O2, the pyrazole ring is approximately coplanar with the amino and carboxyl groups. The phenyl group is twisted by 48.13 (3)° relative to this plane. An intra­molecular N—H⋯O hydrogen bond stabilizes the planar conformation of the mol­ecule. The mol­ecules are linked into two-dimensional sheets by two strong inter­molecular N—H⋯N and O—H⋯O hydrogen bonds. The latter forms the classic carboxylic acid dimer motif.

Related literature

For related literature, see: Baroni & Kovyrzina (1961[Baroni, E. E. & Kovyrzina, K. A. (1961). Zh. Obshch. Khim. 31, 1641-1645.]); Baraldi et al. (1998[Baraldi, P. G., Manfredini, S., Romagnoli, R., Stevanato, L., Zaid, A. N. & Manservigi, R. (1998). Nucleosides Nucleotides, 17, 2165-2171.]); Bruno et al. (1990[Bruno, O., Bondavalli, F., Ranise, A., Schenone, P., Losasso, C., Cilenti, L., Matera, C. & Marmo, E. (1990). Il Farmaco, 45, 147-66.]); Chen & Li (1998[Chen, H. S. & Li, Z. M. (1998). Chem. J. Chin. Univ. 19, 572-576.]); Cottineau et al. (2002[Cottineau, B., Toto, P., Marot, C., Pipaud, A. & Chenault, J. (2002). Bioorg. Med. Chem. 12, 2105-2108.]); Dardari et al. (2006[Dardari, Z., Lemrani, M., Sebban, A., Bahloul, A., Hassair, M., Kitane, S., Berrada, M. & Boudouma, M. (2006). Arch. Pharm. 339, 291-298.]); Jin et al. (2004[Jin, Z.-M., Li, L., Li, M.-C., Hu, M.-L. & Shen, L. (2004). Acta Cryst. C60, o642-o643.]); Li et al. (2006[Li, S.-Y., Zhong, P., Hu, M.-L., Luo, Y. & Li, J.-H. (2006). Acta Cryst. E62, o3821-o3822.]); Londershausen (1996[Londershausen, M. (1996). Pestic. Sci. 48, 269-274.]); Mishra et al. (1998[Mishra, P. D., Wahidullah, S. & Kamat, S. Y. (1998). Indian J. Chem. Sect. B, 37, 199.]); Neunhoeffer et al. (1959[Neunhoeffer, O., Alsdorf, G. & Ulrich, H. (1959). Chem. Ber. 92, 252-256.]); Siddiqui et al. (2007[Siddiqui, H. L., Zia-ur-Rehman, M., Ahmad, N., Weaver, G. W. & Lucas, P. D. (2007). Chem. Pharm. Bull. 55, 1014-1017.]); Smith et al. (2001[Smith, S. R., Denhardt, G. & Terminelli, C. (2001). Eur. J. Pharmacol. 432, 107-119.]); Zhong et al. (2006[Zhong, P., Zhang, X.-H., Xiao, H.-P. & Hu, M.-L. (2006). Acta Cryst. E62, o513-o515.]); Zia-ur-Rehman et al. (2005[Zia-ur-Rehman, M., Choudary, J. A. & Ahmad, S. (2005). Bull. Korean Chem. Soc. 26, 1771-1175.], 2006[Zia-ur-Rehman, M., Choudary, J. A., Ahmad, S. & Siddiqui, H. L. (2006). Chem. Pharm. Bull. 54, 1175-1178.]).

[Scheme 1]

Experimental

Crystal data
  • C10H9N3O2

  • Mr = 203.20

  • Monoclinic, P 21 /n

  • a = 3.7937 (5) Å

  • b = 21.613 (3) Å

  • c = 11.1580 (16) Å

  • β = 92.170 (2)°

  • V = 914.2 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 150 (2) K

  • 0.28 × 0.10 × 0.07 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2007[Sheldrick, G. M. (2007). SADABS. University of Göttingen, Germany.]) Tmin = 0.971, Tmax = 0.993

  • 10482 measured reflections

  • 2800 independent reflections

  • 1967 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.116

  • S = 1.02

  • 2800 reflections

  • 145 parameters

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

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.27 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N4—H4A⋯O3 0.903 (18) 2.136 (18) 2.8233 (16) 132.3 (14)
N4—H4B⋯N3i 0.876 (18) 2.239 (18) 3.0087 (17) 146.5 (15)
O4—H4⋯O3ii 0.92 (2) 1.70 (2) 2.6189 (14) 178.4 (19)
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) -x, -y, -z.

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL and local programs.

Supporting information


Comment top

Pyrazole and its derivatives are known as heterocyclic compounds, having a wide range of biological activities. Some pyrazoles have been reported to possess significant antiarrhythmic and sedative (Bruno et al., 1990), hypoglycemic (Cottineau et al., 2002), antiviral (Baraldi et al., 1998), and pesticidal (Londershausen,1996) activities. Some of their derivatives have also been successfully tested for their antifungal (Chen & Li, 1998), antihistaminic (Mishra et al., 1998) and anti-inflammatory (Smith et al., 2001) activities. In addition, they have also been used as ligands to investigate the structure–activity relationship of the active site of metalloproteins (Dardari et al., 2006) and for the preparation of some 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 (Zia-ur-Rehman et al., 2005, 2006; Siddiqui et al., 2007), the crystal structure of the title compound, (I), was determined. In (I), the pyrazole ring is approximately co-planar with the amino and carboxylic acid groups. The C—N bond lengths in the pyrazole ring are 1.3146 (18) and 1.3530 (16) Å, which are shorter than a typical C—N single bond length of 1.443 Å, but longer than a typical C—N bond length of 1.269 Å (Jin et al., 2004), indicating electron delocalization. Most of the bond lengths and angles in N-phenylpyrazole group are in consistent with those in similar molecules (Li et al., 2006; Zhong et al., 2006). Each molecule exhibits an intramolecular N—H···O hydrogen bond which stabilizes the planar conformation and is linked to an adjacent one through head-to-tail pairs of O—H···O intermolecular interactions giving rise to dimeric motifs typical for carboxylic acids. Neighbouring dimers are further arranged into two-dimensional sheets in the (101) plane through N—H···N interactions (Fig.2).

Related literature top

For related literature, see: Baroni & Kovyrzina (1961); Baraldi et al. (1998); Bruno et al. (1990); Chen & Li (1998); Cottineau et al. (2002); Dardari et al. (2006); Jin et al. (2004); Li et al. (2006); Londershausen (1996); Mishra et al. (1998); Neunhoeffer et al. (1959); Siddiqui et al. (2007); Smith et al. (2001); Zhong et al. (2006); Zia-ur-Rehman et al. (2005, 2006).

Experimental top

A mixture of 5-amino-1-phenyl-1H-pyrazole-4-carboxylic acid, ethyl ester (2.312 g; 10.0 mmoles), potassium hydroxide (1.12 g; 20 mmoles) and ethanol (25 ml) was refluxed for two hours. The reaction mixture was poured into ice cooled water and acidified with dilute hydrochloric acid to Congo Red. The precipitated solids were collected by filtration, washed and dried. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of solution of the title compound in a mixture of ethanol and water (85:15); m.p. 460 K; yield: 68%.

Refinement top

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

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); 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: SHELXTL (Sheldrick, 2008) and local programs.

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] 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.
5-Amino-1-phenyl-1H-pyrazole-4-carboxylic acid top
Crystal data top
C10H9N3O2F(000) = 424
Mr = 203.20Dx = 1.476 Mg m3
Monoclinic, P21/nMelting point: 460 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 3.7937 (5) ÅCell parameters from 2299 reflections
b = 21.613 (3) Åθ = 3.4–29.6°
c = 11.1580 (16) ŵ = 0.11 mm1
β = 92.170 (2)°T = 150 K
V = 914.2 (2) Å3Block, colourless
Z = 40.28 × 0.10 × 0.07 mm
Data collection top
Bruker APEXII CCD
diffractometer
2800 independent reflections
Radiation source: fine-focus sealed tube1967 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ω rotation with narrow frames scansθmax = 30.6°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
h = 55
Tmin = 0.971, Tmax = 0.993k = 3030
10482 measured reflectionsl = 1515
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)] = 0.043Hydrogen site location: geom except NH & OH coords freely refined
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.0521P)2 + 0.3077P]
where P = (Fo2 + 2Fc2)/3
2800 reflections(Δ/σ)max < 0.001
145 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.27 e Å3
Crystal data top
C10H9N3O2V = 914.2 (2) Å3
Mr = 203.20Z = 4
Monoclinic, P21/nMo Kα radiation
a = 3.7937 (5) ŵ = 0.11 mm1
b = 21.613 (3) ÅT = 150 K
c = 11.1580 (16) Å0.28 × 0.10 × 0.07 mm
β = 92.170 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
2800 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)
1967 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.993Rint = 0.034
10482 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.34 e Å3
2800 reflectionsΔρmin = 0.27 e Å3
145 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
C10.0569 (4)0.34024 (6)0.20989 (12)0.0196 (3)
H10.03450.32060.28070.023*
C20.0428 (4)0.40410 (7)0.19887 (13)0.0242 (3)
H20.05480.42840.26280.029*
C30.1711 (4)0.43247 (7)0.09461 (14)0.0262 (3)
H30.16230.47620.08730.031*
C40.3122 (4)0.39693 (7)0.00110 (13)0.0235 (3)
H4C0.39580.41650.07070.028*
C50.3323 (4)0.33300 (6)0.01161 (12)0.0196 (3)
H50.43130.30870.05220.024*
C60.2054 (3)0.30513 (6)0.11682 (11)0.0168 (3)
N20.2312 (3)0.23989 (5)0.13188 (9)0.0172 (2)
N30.3587 (3)0.21589 (5)0.23810 (10)0.0205 (3)
C70.3374 (4)0.15556 (6)0.22523 (12)0.0200 (3)
H70.40840.12680.28390.024*
C80.1976 (4)0.13829 (6)0.11488 (11)0.0175 (3)
C90.1300 (3)0.19438 (6)0.05734 (11)0.0163 (3)
N40.0209 (3)0.20277 (6)0.04849 (10)0.0221 (3)
H4A0.068 (5)0.1668 (8)0.0857 (15)0.027*
H4B0.028 (5)0.2377 (8)0.0881 (16)0.027*
C100.1212 (4)0.07860 (6)0.06630 (12)0.0198 (3)
O30.0099 (3)0.07239 (4)0.03332 (9)0.0247 (2)
O40.1962 (3)0.03107 (5)0.13546 (9)0.0289 (3)
H40.132 (5)0.0050 (10)0.0983 (17)0.043*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0207 (7)0.0229 (7)0.0153 (6)0.0004 (5)0.0039 (5)0.0023 (5)
C20.0263 (7)0.0229 (7)0.0239 (7)0.0054 (6)0.0068 (6)0.0071 (5)
C30.0298 (8)0.0172 (6)0.0324 (8)0.0002 (6)0.0113 (6)0.0003 (5)
C40.0257 (7)0.0229 (7)0.0222 (7)0.0043 (5)0.0052 (5)0.0049 (5)
C50.0210 (7)0.0208 (6)0.0171 (6)0.0009 (5)0.0011 (5)0.0005 (5)
C60.0183 (6)0.0163 (6)0.0161 (6)0.0002 (5)0.0046 (5)0.0009 (5)
N20.0238 (6)0.0162 (5)0.0119 (5)0.0004 (4)0.0040 (4)0.0001 (4)
N30.0285 (6)0.0208 (6)0.0126 (5)0.0010 (5)0.0069 (4)0.0007 (4)
C70.0266 (7)0.0192 (6)0.0144 (6)0.0006 (5)0.0042 (5)0.0011 (5)
C80.0227 (6)0.0164 (6)0.0136 (6)0.0001 (5)0.0029 (5)0.0000 (4)
C90.0195 (6)0.0164 (6)0.0133 (6)0.0004 (5)0.0013 (5)0.0009 (4)
N40.0348 (7)0.0168 (5)0.0153 (5)0.0022 (5)0.0095 (5)0.0009 (4)
C100.0256 (7)0.0173 (6)0.0165 (6)0.0001 (5)0.0034 (5)0.0009 (5)
O30.0384 (6)0.0179 (5)0.0185 (5)0.0016 (4)0.0096 (4)0.0006 (4)
O40.0493 (7)0.0158 (5)0.0228 (5)0.0021 (5)0.0157 (5)0.0022 (4)
Geometric parameters (Å, º) top
C1—C21.387 (2)N2—N31.3968 (15)
C1—C61.3883 (18)N3—C71.3146 (18)
C1—H10.9500C7—C81.4092 (17)
C2—C31.387 (2)C7—H70.9500
C2—H20.9500C8—C91.4001 (17)
C3—C41.387 (2)C8—C101.4331 (18)
C3—H30.9500C9—N41.3438 (16)
C4—C51.3891 (19)N4—H4A0.903 (18)
C4—H4C0.9500N4—H4B0.876 (18)
C5—C61.3891 (18)C10—O31.2423 (16)
C5—H50.9500C10—O41.3221 (16)
C6—N21.4239 (16)O4—H40.92 (2)
N2—C91.3530 (16)
C2—C1—C6119.58 (13)C9—N2—C6128.69 (11)
C2—C1—H1120.2N3—N2—C6119.69 (10)
C6—C1—H1120.2C7—N3—N2104.53 (10)
C3—C2—C1120.06 (13)N3—C7—C8112.64 (12)
C3—C2—H2120.0N3—C7—H7123.7
C1—C2—H2120.0C8—C7—H7123.7
C4—C3—C2119.97 (13)C9—C8—C7104.64 (11)
C4—C3—H3120.0C9—C8—C10124.25 (12)
C2—C3—H3120.0C7—C8—C10131.08 (12)
C3—C4—C5120.55 (13)N4—C9—N2125.61 (12)
C3—C4—H4C119.7N4—C9—C8127.68 (12)
C5—C4—H4C119.7N2—C9—C8106.64 (11)
C4—C5—C6118.97 (13)C9—N4—H4A112.7 (11)
C4—C5—H5120.5C9—N4—H4B125.6 (11)
C6—C5—H5120.5H4A—N4—H4B120.0 (16)
C1—C6—C5120.86 (13)O3—C10—O4122.72 (12)
C1—C6—N2118.73 (12)O3—C10—C8121.96 (12)
C5—C6—N2120.40 (12)O4—C10—C8115.31 (12)
C9—N2—N3111.54 (10)C10—O4—H4109.2 (12)
C6—C1—C2—C31.1 (2)N3—C7—C8—C90.05 (16)
C1—C2—C3—C40.3 (2)N3—C7—C8—C10178.11 (14)
C2—C3—C4—C51.2 (2)N3—N2—C9—N4176.22 (12)
C3—C4—C5—C60.7 (2)C6—N2—C9—N40.3 (2)
C2—C1—C6—C51.6 (2)N3—N2—C9—C80.98 (15)
C2—C1—C6—N2177.34 (12)C6—N2—C9—C8177.55 (13)
C4—C5—C6—C10.7 (2)C7—C8—C9—N4176.51 (14)
C4—C5—C6—N2178.20 (12)C10—C8—C9—N41.7 (2)
C1—C6—N2—C9130.01 (14)C7—C8—C9—N20.62 (15)
C5—C6—N2—C951.1 (2)C10—C8—C9—N2178.85 (13)
C1—C6—N2—N346.33 (17)C9—C8—C10—O30.8 (2)
C5—C6—N2—N3132.62 (13)C7—C8—C10—O3178.56 (14)
C9—N2—N3—C70.93 (15)C9—C8—C10—O4178.38 (13)
C6—N2—N3—C7177.85 (12)C7—C8—C10—O40.7 (2)
N2—N3—C7—C80.51 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···O30.903 (18)2.136 (18)2.8233 (16)132.3 (14)
N4—H4B···N3i0.876 (18)2.239 (18)3.0087 (17)146.5 (15)
O4—H4···O3ii0.92 (2)1.70 (2)2.6189 (14)178.4 (19)
Symmetry codes: (i) x1/2, y+1/2, z+1/2; (ii) x, y, z.

Experimental details

Crystal data
Chemical formulaC10H9N3O2
Mr203.20
Crystal system, space groupMonoclinic, P21/n
Temperature (K)150
a, b, c (Å)3.7937 (5), 21.613 (3), 11.1580 (16)
β (°) 92.170 (2)
V3)914.2 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.28 × 0.10 × 0.07
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2007)
Tmin, Tmax0.971, 0.993
No. of measured, independent and
observed [I > 2σ(I)] reflections
10482, 2800, 1967
Rint0.034
(sin θ/λ)max1)0.716
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.116, 1.02
No. of reflections2800
No. of parameters145
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.34, 0.27

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and local programs.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···O30.903 (18)2.136 (18)2.8233 (16)132.3 (14)
N4—H4B···N3i0.876 (18)2.239 (18)3.0087 (17)146.5 (15)
O4—H4···O3ii0.92 (2)1.70 (2)2.6189 (14)178.4 (19)
Symmetry codes: (i) x1/2, y+1/2, z+1/2; (ii) x, y, z.
 

Acknowledgements

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

References

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Volume 64| Part 7| July 2008| Pages o1312-o1313
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