1-(4-tert-Butyl­benz­yl)-3-phenyl-1H-pyrazole-5-carboxylic acid

Zheng Tang; Xiao-Ling Ding; Yong-Sheng Xie; Bao-Xiang Zhao

doi:10.1107/S1600536809017000

. 2009 May 14;65(Pt 6):o1273. doi: 10.1107/S1600536809017000

1-(4-tert-Butylbenzyl)-3-phenyl-1H-pyrazole-5-carboxylic acid

Zheng Tang ^a, Xiao-Ling Ding ^b, Yong-Sheng Xie ^c, Bao-Xiang Zhao ^c,^*

PMCID: PMC2969815 PMID: 21583135

Abstract

In the title compound, C₂₁H₂₂N₂O₂, the mean plane of the pyrazole ring makes dihedral angles of 18.80 (12) and 77.13 (5)°, respectively, with the mean planes of the phenyl and tert-butylbenzyl rings. The carboxylate group is inclined at 8.51 (14)° with respect to the pyrazole ring. The crystal structure displays intermolecular O—H⋯O hydrogen bonding, generating centrosymmetric dimers.

Related literature

For the synthesis and biological activity of related compounds, see: Wei et al. (2006 ▶); Xia et al. (2007b ▶); Zhang et al. (2008 ▶); Zhao et al. (2008 ▶). For related structures, see: Ding et al. (2007 ▶); Tang et al. (2007 ▶); Xia et al. (2007a ▶).

Experimental

Crystal data

C₂₁H₂₂N₂O₂
M _r = 334.41
Monoclinic,
a = 12.336 (2) Å
b = 17.632 (3) Å
c = 8.7876 (17) Å
β = 97.910 (3)°
V = 1893.2 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 K
0.16 × 0.13 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.988, T _max = 0.992
10007 measured reflections
3552 independent reflections
2644 reflections with I > 2σ(I)
R _int = 0.021

Refinement

R[F ² > 2σ(F ²)] = 0.052
wR(F ²) = 0.166
S = 1.02
3552 reflections
231 parameters
H-atom parameters constrained
Δρ_max = 0.56 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Data collection: SMART (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809017000/pv2149sup1.cif

e-65-o1273-sup1.cif^{(20.5KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809017000/pv2149Isup2.hkl

e-65-o1273-Isup2.hkl^{(170.7KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O2ⁱ	0.82	1.82	2.641 (2)	178

Open in a new tab

Symmetry code: (i) Inline graphic .

Acknowledgments

This study was supported by the Science and Technology Developmental Project of Shandong Province (grant No. 2008GG10002034).

supplementary crystallographic information

Comment

The pyrazole unit is one of the core structures in a number of natural products. Many pyrazole derivatives are known to exhibit a wide range of biological properties such as antitumor (Wei et al., 2006). As a part of our continuing project on the study of synthesis and bioactivity evaluation of pyrazole derivatives (Xia et al., 2007b; Zhao et al., 2008; Zhang et al., 2008), we report here the synthesis and crystal structure of the title compound.

In the title compound (Fig. 1), the pyrazole ring makes dihedral angles of 18.80 (12) and 77.13 (5)° with the phenyl and tert-butylbenzyl rings, respectively. The oxalate group is inclined at 8.51 (14)° with respect to the pyrazole ring. The crystal structure displays a strong intermolecular interaction which leads to the formation of hydrogen bonded dimeric units (Table 1) about inversion centers which is typical of organic carboxylic acids (Ding et al., 2007). The crystal structures of a few related compounds have been reported from our laboratory, e.g. (Ding et al., 2007; Xia et al., 2007a; Tang et al., 2007)

Experimental

A mixture of ethyl 1-(4-tert-Butylbenzyl)-3-phenyl-1H-pyrazole-5-carboxylate (0.01 mol) and potassium hydroxide (0.02 mol) in ethanol (40 ml) was heated to reflux for 3 h. The solvent was removed under reduced pressure and the residue was dissolved in water and acidified with hydrochloric acid (10%). The precipitate was filtered and dried to give a white solid (yield 92%). Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of a solution of the solid in acetone at room temperature for 3 d.