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

Tang, Z.; Ding, X.-L.; Xie, Y.-S.; Zhao, B.-X.

doi:10.1107/S1600536809017000

organic compounds

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ISSN: 2056-9890

Volume 65| Part 6| June 2009| Page o1273

doi:10.1107/S1600536809017000

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

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

^aSubmarine College of Navy, Qingdao 266071, People's Republic of China, ^bCollege of Advanced Professional Technology, Qingdao University, Qingdao 266061, People's Republic of China, and ^cSchool of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
^*Correspondence e-mail: bxzhao@sdu.edu.cn

(Received 24 March 2009; accepted 5 May 2009; online 14 May 2009)

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, P 2₁ /c
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[F² > 2σ(F²)] = 0.052
wR(F²) = 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

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
Symmetry code: (i) -x+2, -y, -z+1.

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.

Supporting information

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

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

checkCIF report

Comment top

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)

Related literature top

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 top

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.

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), with displacement ellipsoids drawn at the 30% probability level.

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

Crystal data top

C₂₁H₂₂N₂O₂	F(000) = 712
M_r = 334.41	D_x = 1.173 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3769 reflections
a = 12.336 (2) Å	θ = 2.3–27.1°
b = 17.632 (3) Å	µ = 0.08 mm⁻¹
c = 8.7876 (17) Å	T = 298 K
β = 97.910 (3)°	Block, colourless
V = 1893.2 (6) Å³	0.16 × 0.13 × 0.10 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	3552 independent reflections
Radiation source: fine-focus sealed tube	2644 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 26.1°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −12→15
T_min = 0.988, T_max = 0.992	k = −21→21
10007 measured reflections	l = −10→7

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.052	H-atom parameters constrained
wR(F²) = 0.166	w = 1/[σ²(F_o²) + (0.0935P)² + 0.4012P] where P = (F_o² + 2F_c²)/3
S = 1.02	(Δ/σ)_max = 0.001
3552 reflections	Δρ_max = 0.56 e Å⁻³
231 parameters	Δρ_min = −0.27 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0065 (19)

Crystal data top

C₂₁H₂₂N₂O₂	V = 1893.2 (6) Å³
M_r = 334.41	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 12.336 (2) Å	µ = 0.08 mm⁻¹
b = 17.632 (3) Å	T = 298 K
c = 8.7876 (17) Å	0.16 × 0.13 × 0.10 mm
β = 97.910 (3)°

Data collection top

Bruker SMART CCD area-detector diffractometer	3552 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2644 reflections with I > 2σ(I)
T_min = 0.988, T_max = 0.992	R_int = 0.021
10007 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.166	H-atom parameters constrained
S = 1.02	Δρ_max = 0.56 e Å⁻³
3552 reflections	Δρ_min = −0.27 e Å⁻³
231 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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

	x	y	z	U_iso*/U_eq
O1	1.06981 (13)	0.07159 (8)	0.39610 (19)	0.0671 (4)
H1	1.0670	0.0259	0.4125	0.101*
O2	0.94281 (12)	0.07589 (8)	0.5566 (2)	0.0633 (4)
N1	0.95215 (12)	0.23985 (8)	0.53903 (17)	0.0443 (4)
N2	0.98423 (12)	0.31199 (8)	0.52234 (17)	0.0467 (4)
C1	1.00463 (15)	0.10731 (11)	0.4774 (2)	0.0512 (5)
C2	1.01498 (14)	0.19024 (10)	0.4691 (2)	0.0469 (4)
C3	1.09088 (14)	0.23321 (11)	0.4044 (2)	0.0489 (4)
H3	1.1445	0.2157	0.3484	0.059*
C4	1.06969 (14)	0.30870 (10)	0.4412 (2)	0.0451 (4)
C5	1.12601 (14)	0.37881 (11)	0.4041 (2)	0.0491 (5)
C6	1.19031 (17)	0.38040 (14)	0.2862 (3)	0.0629 (5)
H6	1.2004	0.3363	0.2318	0.075*
C7	1.2401 (2)	0.44801 (18)	0.2487 (3)	0.0776 (7)
H7	1.2830	0.4484	0.1695	0.093*
C8	1.2262 (2)	0.51358 (16)	0.3277 (4)	0.0820 (8)
H8	1.2583	0.5585	0.3012	0.098*
C9	1.1646 (2)	0.51239 (14)	0.4457 (4)	0.0803 (8)
H9	1.1556	0.5567	0.4999	0.096*
C10	1.11504 (17)	0.44554 (12)	0.4858 (3)	0.0647 (6)
H10	1.0745	0.4455	0.5675	0.078*
C11	0.86035 (15)	0.22509 (11)	0.6259 (2)	0.0488 (4)
H11A	0.8471	0.2703	0.6836	0.059*
H11B	0.8810	0.1847	0.6991	0.059*
C12	0.75498 (14)	0.20293 (10)	0.5253 (2)	0.0439 (4)
C13	0.70381 (16)	0.25233 (12)	0.4155 (2)	0.0563 (5)
H13	0.7353	0.2993	0.4014	0.068*
C14	0.60599 (16)	0.23267 (14)	0.3261 (3)	0.0630 (6)
H14	0.5739	0.2667	0.2525	0.076*
C15	0.55480 (15)	0.16391 (13)	0.3434 (2)	0.0550 (5)
C16	0.60596 (16)	0.11511 (12)	0.4557 (3)	0.0581 (5)
H16	0.5734	0.0688	0.4718	0.070*
C17	0.70455 (15)	0.13405 (11)	0.5443 (2)	0.0525 (5)
H17	0.7371	0.0999	0.6174	0.063*
C18	0.44732 (18)	0.14091 (16)	0.2427 (3)	0.0751 (7)
C19	0.4710 (3)	0.0946 (3)	0.1148 (6)	0.185 (3)
H19A	0.4903	0.0443	0.1506	0.277*
H19B	0.5309	0.1165	0.0709	0.277*
H19C	0.4076	0.0924	0.0383	0.277*
C20	0.3864 (3)	0.2129 (3)	0.1715 (6)	0.151 (2)
H20A	0.4274	0.2350	0.0975	0.227*
H20B	0.3794	0.2490	0.2513	0.227*
H20C	0.3150	0.1988	0.1219	0.227*
C21	0.3666 (3)	0.1096 (3)	0.3438 (5)	0.148 (2)
H21A	0.2932	0.1199	0.2967	0.222*
H21B	0.3792	0.1334	0.4429	0.222*
H21C	0.3767	0.0558	0.3553	0.222*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0727 (10)	0.0507 (8)	0.0822 (11)	0.0079 (7)	0.0261 (8)	0.0001 (7)
O2	0.0514 (8)	0.0513 (8)	0.0893 (11)	0.0027 (6)	0.0172 (8)	0.0011 (7)
N1	0.0354 (7)	0.0495 (8)	0.0459 (8)	−0.0024 (6)	−0.0012 (6)	−0.0039 (6)
N2	0.0380 (8)	0.0489 (8)	0.0510 (9)	−0.0027 (6)	−0.0009 (6)	−0.0040 (6)
C1	0.0404 (10)	0.0509 (10)	0.0596 (11)	0.0039 (8)	−0.0021 (8)	−0.0019 (8)
C2	0.0369 (9)	0.0495 (10)	0.0517 (10)	0.0034 (7)	−0.0025 (8)	−0.0008 (8)
C3	0.0362 (9)	0.0543 (11)	0.0551 (11)	0.0057 (7)	0.0024 (8)	0.0004 (8)
C4	0.0322 (8)	0.0537 (10)	0.0466 (9)	0.0018 (7)	−0.0045 (7)	0.0006 (7)
C5	0.0321 (9)	0.0558 (10)	0.0563 (11)	0.0025 (7)	−0.0055 (8)	0.0072 (8)
C6	0.0485 (11)	0.0788 (14)	0.0604 (12)	−0.0038 (10)	0.0045 (9)	0.0025 (10)
C7	0.0564 (13)	0.102 (2)	0.0754 (16)	−0.0117 (12)	0.0110 (11)	0.0205 (14)
C8	0.0559 (14)	0.0742 (17)	0.114 (2)	−0.0116 (11)	0.0055 (14)	0.0295 (15)
C9	0.0598 (14)	0.0591 (13)	0.123 (2)	−0.0048 (10)	0.0163 (14)	0.0034 (13)
C10	0.0493 (11)	0.0559 (12)	0.0906 (16)	−0.0013 (9)	0.0159 (11)	−0.0021 (11)
C11	0.0436 (10)	0.0590 (11)	0.0434 (9)	−0.0048 (8)	0.0043 (8)	−0.0049 (8)
C12	0.0363 (9)	0.0530 (10)	0.0430 (9)	−0.0008 (7)	0.0076 (7)	−0.0061 (7)
C13	0.0421 (10)	0.0633 (12)	0.0634 (12)	−0.0089 (8)	0.0069 (9)	0.0134 (9)
C14	0.0412 (10)	0.0838 (15)	0.0624 (13)	−0.0037 (9)	0.0016 (9)	0.0231 (11)
C15	0.0344 (9)	0.0760 (13)	0.0546 (11)	−0.0022 (8)	0.0062 (8)	−0.0029 (9)
C16	0.0435 (10)	0.0521 (11)	0.0772 (14)	−0.0076 (8)	0.0029 (9)	−0.0051 (9)
C17	0.0455 (10)	0.0488 (10)	0.0611 (12)	0.0011 (8)	−0.0004 (9)	0.0014 (8)
C18	0.0397 (11)	0.1038 (19)	0.0782 (16)	−0.0116 (11)	−0.0042 (10)	−0.0058 (13)
C19	0.072 (2)	0.270 (7)	0.196 (5)	0.018 (3)	−0.036 (3)	−0.159 (5)
C20	0.077 (2)	0.157 (4)	0.195 (5)	0.009 (2)	−0.067 (3)	−0.013 (3)
C21	0.0644 (19)	0.220 (5)	0.151 (4)	−0.052 (3)	−0.013 (2)	0.029 (3)

Geometric parameters (Å, º) top

O1—C1	1.308 (2)	C11—H11B	0.9700
O1—H1	0.8200	C12—C17	1.385 (3)
O2—C1	1.233 (3)	C12—C13	1.385 (3)
N1—N2	1.346 (2)	C13—C14	1.390 (3)
N1—C2	1.369 (2)	C13—H13	0.9300
N1—C11	1.473 (2)	C14—C15	1.385 (3)
N2—C4	1.352 (2)	C14—H14	0.9300
C1—C2	1.470 (3)	C15—C16	1.393 (3)
C2—C3	1.386 (3)	C15—C18	1.544 (3)
C3—C4	1.403 (3)	C16—C17	1.391 (3)
C3—H3	0.9300	C16—H16	0.9300
C4—C5	1.477 (3)	C17—H17	0.9300
C5—C6	1.389 (3)	C18—C19	1.451 (5)
C5—C10	1.395 (3)	C18—C21	1.525 (5)
C6—C7	1.401 (4)	C18—C20	1.561 (5)
C6—H6	0.9300	C19—H19A	0.9600
C7—C8	1.372 (4)	C19—H19B	0.9600
C7—H7	0.9300	C19—H19C	0.9600
C8—C9	1.367 (4)	C20—H20A	0.9600
C8—H8	0.9300	C20—H20B	0.9600
C9—C10	1.395 (3)	C20—H20C	0.9600
C9—H9	0.9300	C21—H21A	0.9600
C10—H10	0.9300	C21—H21B	0.9600
C11—C12	1.519 (2)	C21—H21C	0.9600
C11—H11A	0.9700

C1—O1—H1	109.5	C17—C12—C11	121.19 (16)
N2—N1—C2	111.20 (15)	C13—C12—C11	120.99 (17)
N2—N1—C11	118.80 (15)	C12—C13—C14	120.89 (18)
C2—N1—C11	129.99 (16)	C12—C13—H13	119.6
N1—N2—C4	106.21 (14)	C14—C13—H13	119.6
O2—C1—O1	124.52 (19)	C15—C14—C13	122.00 (19)
O2—C1—C2	122.64 (18)	C15—C14—H14	119.0
O1—C1—C2	112.81 (18)	C13—C14—H14	119.0
N1—C2—C3	106.92 (16)	C14—C15—C16	116.70 (17)
N1—C2—C1	123.70 (17)	C14—C15—C18	122.4 (2)
C3—C2—C1	129.20 (17)	C16—C15—C18	120.9 (2)
C2—C3—C4	105.44 (17)	C17—C16—C15	121.59 (19)
C2—C3—H3	127.3	C17—C16—H16	119.2
C4—C3—H3	127.3	C15—C16—H16	119.2
N2—C4—C3	110.23 (16)	C12—C17—C16	121.04 (18)
N2—C4—C5	120.35 (16)	C12—C17—H17	119.5
C3—C4—C5	129.42 (18)	C16—C17—H17	119.5
C6—C5—C10	118.23 (19)	C19—C18—C21	117.7 (4)
C6—C5—C4	121.08 (19)	C19—C18—C15	110.1 (2)
C10—C5—C4	120.68 (18)	C21—C18—C15	109.8 (2)
C5—C6—C7	120.4 (2)	C19—C18—C20	106.5 (4)
C5—C6—H6	119.8	C21—C18—C20	102.2 (3)
C7—C6—H6	119.8	C15—C18—C20	110.2 (2)
C8—C7—C6	120.6 (2)	C18—C19—H19A	109.5
C8—C7—H7	119.7	C18—C19—H19B	109.5
C6—C7—H7	119.7	H19A—C19—H19B	109.5
C9—C8—C7	119.5 (2)	C18—C19—H19C	109.5
C9—C8—H8	120.2	H19A—C19—H19C	109.5
C7—C8—H8	120.2	H19B—C19—H19C	109.5
C8—C9—C10	120.9 (3)	C18—C20—H20A	109.5
C8—C9—H9	119.6	C18—C20—H20B	109.5
C10—C9—H9	119.6	H20A—C20—H20B	109.5
C5—C10—C9	120.4 (2)	C18—C20—H20C	109.5
C5—C10—H10	119.8	H20A—C20—H20C	109.5
C9—C10—H10	119.8	H20B—C20—H20C	109.5
N1—C11—C12	113.64 (14)	C18—C21—H21A	109.5
N1—C11—H11A	108.8	C18—C21—H21B	109.5
C12—C11—H11A	108.8	H21A—C21—H21B	109.5
N1—C11—H11B	108.8	C18—C21—H21C	109.5
C12—C11—H11B	108.8	H21A—C21—H21C	109.5
H11A—C11—H11B	107.7	H21B—C21—H21C	109.5
C17—C12—C13	117.77 (16)

C2—N1—N2—C4	−0.45 (18)	C7—C8—C9—C10	−0.6 (4)
C11—N1—N2—C4	179.05 (14)	C6—C5—C10—C9	2.2 (3)
N2—N1—C2—C3	−0.09 (19)	C4—C5—C10—C9	−177.19 (19)
C11—N1—C2—C3	−179.51 (16)	C8—C9—C10—C5	−1.1 (4)
N2—N1—C2—C1	175.41 (15)	N2—N1—C11—C12	106.44 (18)
C11—N1—C2—C1	−4.0 (3)	C2—N1—C11—C12	−74.2 (2)
O2—C1—C2—N1	−4.8 (3)	N1—C11—C12—C17	120.67 (19)
O1—C1—C2—N1	177.14 (16)	N1—C11—C12—C13	−62.0 (2)
O2—C1—C2—C3	169.67 (19)	C17—C12—C13—C14	−1.0 (3)
O1—C1—C2—C3	−8.4 (3)	C11—C12—C13—C14	−178.41 (19)
N1—C2—C3—C4	0.56 (19)	C12—C13—C14—C15	0.8 (3)
C1—C2—C3—C4	−174.60 (17)	C13—C14—C15—C16	0.3 (3)
N1—N2—C4—C3	0.81 (19)	C13—C14—C15—C18	−178.8 (2)
N1—N2—C4—C5	−179.17 (14)	C14—C15—C16—C17	−1.0 (3)
C2—C3—C4—N2	−0.87 (19)	C18—C15—C16—C17	178.0 (2)
C2—C3—C4—C5	179.11 (16)	C13—C12—C17—C16	0.2 (3)
N2—C4—C5—C6	−160.76 (17)	C11—C12—C17—C16	177.62 (18)
C3—C4—C5—C6	19.3 (3)	C15—C16—C17—C12	0.8 (3)
N2—C4—C5—C10	18.6 (3)	C14—C15—C18—C19	95.8 (4)
C3—C4—C5—C10	−161.36 (19)	C16—C15—C18—C19	−83.2 (4)
C10—C5—C6—C7	−1.7 (3)	C14—C15—C18—C21	−133.1 (3)
C4—C5—C6—C7	177.74 (18)	C16—C15—C18—C21	47.9 (4)
C5—C6—C7—C8	0.0 (4)	C14—C15—C18—C20	−21.3 (4)
C6—C7—C8—C9	1.1 (4)	C16—C15—C18—C20	159.6 (3)

Hydrogen-bond geometry (Å, º) top

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

Symmetry code: (i) −x+2, −y, −z+1.

Experimental details

Crystal data
Chemical formula	C₂₁H₂₂N₂O₂
M_r	334.41
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	12.336 (2), 17.632 (3), 8.7876 (17)
β (°)	97.910 (3)
V (Å³)	1893.2 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.16 × 0.13 × 0.10

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.988, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	10007, 3552, 2644
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.166, 1.02
No. of reflections	3552
No. of parameters	231
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.56, −0.27

Computer programs: SMART (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O2ⁱ	0.82	1.82	2.641 (2)	178.1

Symmetry code: (i) −x+2, −y, −z+1.

Acknowledgements

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

References

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