[3,5-Bis(benz­yloxy)phen­yl]methanol

Zhu, P.-H.; Ni, Z.-Z.; Dong, C.-H.; Zhao, Y.-F.; Wei, Q.

doi:10.1107/S1600536809010757

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Page o962

doi:10.1107/S1600536809010757

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[3,5-Bis(benzyloxy)phenyl]methanol

Pei-Hua Zhu,^a ^* Zi-Zhen Ni,^a Chun-Hui Dong,^a Yan-Fang Zhao ^a and Qin Wei ^a

^aSchool of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China
^*Correspondence e-mail: chm_zhuph@ujn.edu.cn

(Received 12 March 2009; accepted 24 March 2009; online 8 April 2009)

In the title compound, C₂₁H₂₀O₃, the two terminal phenyl rings are each approximately perpendicular to the central benzene ring, making dihedral angles of 84.40 (16) and 75.12 (15)°. The H atom of the hydroxy group is disordered over two positions with equal occupancies. The molecules are linked by O—H⋯O hydrogen bonds, forming a chain along the a axis.

Related literature

For related compounds, see: Rheiner & Seebach (1999 ); Pan et al. (2005 ); Xiao et al. (2007 ). For the synthesis, see: Hawker & Fréchet (1990 ).

Experimental

Crystal data

C₂₁H₂₀O₃
M_r = 320.37
Triclinic, $[P \overline 1]$
a = 4.8555 (6) Å
b = 12.2442 (18) Å
c = 15.017 (2) Å
α = 74.049 (1)°
β = 83.293 (1)°
γ = 89.733 (2)°
V = 852.2 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 K
0.46 × 0.16 × 0.15 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.963, T_max = 0.988
4355 measured reflections
2909 independent reflections
1563 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.057
wR(F²) = 0.168
S = 0.99
2909 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O3ⁱ	0.87	1.98	2.791 (4)	155
O3—H3′⋯O3ⁱⁱ	0.86	1.95	2.805 (5)	179
Symmetry codes: (i) -x+3, -y+1, -z+1; (ii) -x+2, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809010757/is2400sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809010757/is2400Isup2.hkl

checkCIF report

Comment top

Dendrimers are three-dimensional hyperbranched macromolecules that provide well defined nanoscopic objects at the single molecular level. Recent studies on dendritic macromolecules have extended the scope of research from synthesis to applications for catalysts, photoactive and electronic materials, medicinal and biomedical materials, and other functional materials. As a part of our structural investigations on dendritic macromolecules, the single-crystal X-ray diffraction study on the title compound was carried out.

In the title compound, the bond lengths and angles are within the normal ranges. Each unit cell of the title compound contains two molecules like other analogues reported before (Pan et al., 2005; Rheiner & Seebach, 1999; Xiao et al., 2007). It is worth noting that the dihedral angles between the central benzene ring and the two peripheral phenyl rings are 84.40 (16) and 75.12 (15)°. Probably because of the effects of substitution of the central benzene ring, the dihedral angels of the title compound are different from ones reported (Xiao et al., 2007). The O—CH₂ bonds lie in the plane of the central phenyl ring and adopt a syn, anti conformation (Pan et al., 2005). The crystal structure is stabilized by intermolecular hydrogen bonds.

Related literature top

For related compounds, see: Rheiner & Seebach (1999); Pan et al. (2005); Xiao et al. (2007). For the synthesis, see: Hawker & Fréchet (1990).

Experimental top

Benzylbromide (10.0 g, 58 mmol), 3,5-dihydroxybenzyl alcohol (4.10 g, 129 mmol), 18-crown-6-ether (1.54 g, 5.8 mmol) and potassium carbonate (16 g, 578.6 mmol) were suspended in 500 ml of 2-butanone under nitrogen atmosphere. The mixture was heated under reflux for 48 h. Upon completion of the reaction, the solvent was evaporated and the water and dichloromethanewere added to the residue. Conventional workup and purification by silica-gel column chromatography (eluent: dichloromethane) yielded 5.6 g of the title compound (60%) as a white needle (Hawker & Fréchet, 1990). Single crystals suitable for X-ray study were grown by diffusion method [dichloromethane/n-hexane (1:4 v/v)] at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); 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).

Figures top

Fig. 1. The molecular structure, with atom labels and 25% probability displacement ellipsoids for non-H atoms.

[3,5-Bis(benzyloxy)phenyl]methanol top

Crystal data top

C₂₁H₂₀O₃	Z = 2
M_r = 320.37	F(000) = 340
Triclinic, P1	D_x = 1.249 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.8555 (6) Å	Cell parameters from 1252 reflections
b = 12.2442 (18) Å	θ = 2.5–23.9°
c = 15.017 (2) Å	µ = 0.08 mm⁻¹
α = 74.049 (1)°	T = 298 K
β = 83.293 (1)°	Needle, colorless
γ = 89.733 (2)°	0.46 × 0.16 × 0.15 mm
V = 852.2 (2) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	2909 independent reflections
Radiation source: fine-focus sealed tube	1563 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 25.0°, θ_min = 1.4°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −5→5
T_min = 0.963, T_max = 0.988	k = −14→13
4355 measured reflections	l = −17→17

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.168	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0808P)²] where P = (F_o² + 2F_c²)/3
2909 reflections	(Δ/σ)_max = 0.001
217 parameters	Δρ_max = 0.37 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₂₁H₂₀O₃	γ = 89.733 (2)°
M_r = 320.37	V = 852.2 (2) Å³
Triclinic, P1	Z = 2
a = 4.8555 (6) Å	Mo Kα radiation
b = 12.2442 (18) Å	µ = 0.08 mm⁻¹
c = 15.017 (2) Å	T = 298 K
α = 74.049 (1)°	0.46 × 0.16 × 0.15 mm
β = 83.293 (1)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	2909 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	1563 reflections with I > 2σ(I)
T_min = 0.963, T_max = 0.988	R_int = 0.035
4355 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.057	0 restraints
wR(F²) = 0.168	H-atom parameters constrained
S = 0.99	Δρ_max = 0.37 e Å⁻³
2909 reflections	Δρ_min = −0.21 e Å⁻³
217 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

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.7476 (4)	0.54725 (14)	0.18038 (12)	0.0568 (6)
O2	0.7536 (4)	0.14526 (14)	0.29783 (13)	0.0635 (6)
O3	1.2666 (5)	0.48874 (17)	0.45678 (15)	0.0789 (7)
H3	1.3738	0.4982	0.4970	0.095*	0.50
H3'	1.1026	0.4958	0.4828	0.095*	0.50
C1	0.8253 (5)	0.4491 (2)	0.24052 (17)	0.0426 (6)
C2	0.7487 (5)	0.34076 (19)	0.23990 (17)	0.0453 (7)
H2A	0.6341	0.3299	0.1974	0.054*
C3	0.8453 (6)	0.2488 (2)	0.30348 (18)	0.0464 (7)
C4	1.0120 (6)	0.2635 (2)	0.36729 (18)	0.0480 (7)
H4A	1.0747	0.2007	0.4098	0.058*
C5	1.0871 (5)	0.3729 (2)	0.36817 (17)	0.0425 (6)
C6	0.9927 (5)	0.4648 (2)	0.30581 (17)	0.0438 (7)
H6A	1.0402	0.5379	0.3069	0.053*
C7	0.5903 (6)	0.5371 (2)	0.10822 (18)	0.0533 (7)
H7A	0.4095	0.5024	0.1351	0.064*
H7B	0.6854	0.4897	0.0729	0.064*
C8	0.5585 (6)	0.6536 (2)	0.04585 (18)	0.0496 (7)
C9	0.7312 (7)	0.6937 (3)	−0.0356 (2)	0.0754 (10)
H9A	0.8676	0.6473	−0.0528	0.090*
C10	0.7059 (10)	0.8012 (3)	−0.0920 (3)	0.0962 (13)
H10A	0.8263	0.8274	−0.1467	0.115*
C11	0.5067 (10)	0.8696 (3)	−0.0687 (3)	0.0908 (12)
H11A	0.4883	0.9422	−0.1076	0.109*
C12	0.3331 (9)	0.8312 (3)	0.0124 (3)	0.1023 (13)
H12A	0.1982	0.8781	0.0297	0.123*
C13	0.3587 (8)	0.7224 (3)	0.0687 (2)	0.0794 (10)
H13A	0.2372	0.6959	0.1232	0.095*
C14	0.8719 (7)	0.0468 (2)	0.3518 (2)	0.0680 (9)
H14A	0.8331	0.0422	0.4176	0.082*
H14B	1.0716	0.0501	0.3354	0.082*
C15	0.7497 (7)	−0.0552 (2)	0.3328 (2)	0.0557 (8)
C16	0.8521 (8)	−0.0914 (3)	0.2569 (2)	0.0772 (10)
H16A	0.9985	−0.0510	0.2158	0.093*
C17	0.7416 (8)	−0.1859 (3)	0.2410 (3)	0.0869 (11)
H17A	0.8147	−0.2090	0.1893	0.104*
C18	0.5285 (9)	−0.2461 (3)	0.2992 (3)	0.0790 (11)
H18A	0.4561	−0.3106	0.2880	0.095*
C19	0.4214 (8)	−0.2119 (3)	0.3736 (3)	0.0840 (11)
H19A	0.2732	−0.2526	0.4136	0.101*
C20	0.5308 (7)	−0.1165 (3)	0.3910 (2)	0.0724 (9)
H20A	0.4552	−0.0937	0.4427	0.087*
C21	1.2750 (6)	0.3847 (2)	0.43799 (19)	0.0533 (7)
H21C	1.2243	0.3258	0.4958	0.064*
H21A	1.4641	0.3721	0.4148	0.064*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0814 (15)	0.0381 (10)	0.0525 (11)	−0.0110 (9)	−0.0322 (10)	−0.0052 (9)
O2	0.0863 (16)	0.0319 (10)	0.0791 (14)	0.0001 (9)	−0.0387 (12)	−0.0149 (9)
O3	0.0913 (17)	0.0735 (14)	0.0969 (17)	0.0106 (12)	−0.0500 (14)	−0.0495 (13)
C1	0.0504 (17)	0.0370 (14)	0.0399 (14)	−0.0060 (12)	−0.0073 (12)	−0.0090 (12)
C2	0.0548 (18)	0.0405 (15)	0.0447 (15)	−0.0049 (12)	−0.0162 (13)	−0.0141 (12)
C3	0.0544 (18)	0.0364 (14)	0.0529 (16)	−0.0019 (12)	−0.0106 (14)	−0.0179 (13)
C4	0.0553 (18)	0.0407 (15)	0.0521 (16)	0.0023 (12)	−0.0168 (14)	−0.0156 (13)
C5	0.0382 (15)	0.0501 (16)	0.0421 (14)	−0.0022 (12)	−0.0080 (12)	−0.0166 (13)
C6	0.0480 (17)	0.0412 (15)	0.0451 (14)	−0.0094 (12)	−0.0073 (13)	−0.0162 (12)
C7	0.067 (2)	0.0495 (17)	0.0465 (15)	−0.0089 (14)	−0.0208 (14)	−0.0128 (13)
C8	0.0575 (19)	0.0477 (16)	0.0469 (16)	−0.0056 (14)	−0.0173 (14)	−0.0139 (13)
C9	0.090 (3)	0.064 (2)	0.064 (2)	−0.0044 (18)	0.0077 (19)	−0.0125 (18)
C10	0.131 (4)	0.074 (3)	0.065 (2)	−0.018 (2)	0.002 (2)	0.005 (2)
C11	0.114 (3)	0.060 (2)	0.087 (3)	−0.006 (2)	−0.039 (3)	0.010 (2)
C12	0.109 (3)	0.073 (3)	0.112 (3)	0.023 (2)	−0.015 (3)	−0.002 (2)
C13	0.082 (3)	0.073 (2)	0.070 (2)	0.014 (2)	−0.0027 (18)	0.0004 (18)
C14	0.097 (3)	0.0410 (16)	0.073 (2)	0.0056 (16)	−0.0391 (18)	−0.0153 (15)
C15	0.072 (2)	0.0330 (15)	0.0616 (19)	0.0019 (14)	−0.0210 (16)	−0.0064 (14)
C16	0.088 (3)	0.059 (2)	0.086 (2)	−0.0220 (18)	0.009 (2)	−0.0278 (18)
C17	0.093 (3)	0.072 (2)	0.109 (3)	−0.006 (2)	−0.003 (2)	−0.050 (2)
C18	0.092 (3)	0.0474 (19)	0.102 (3)	−0.0107 (19)	−0.037 (2)	−0.019 (2)
C19	0.084 (3)	0.069 (2)	0.088 (3)	−0.028 (2)	−0.020 (2)	0.001 (2)
C20	0.081 (3)	0.070 (2)	0.065 (2)	0.0024 (19)	−0.0113 (19)	−0.0148 (18)
C21	0.0524 (18)	0.0574 (17)	0.0596 (18)	0.0020 (14)	−0.0189 (14)	−0.0267 (15)

Geometric parameters (Å, º) top

O1—C1	1.371 (3)	C10—C11	1.354 (5)
O1—C7	1.429 (3)	C10—H10A	0.9300
O2—C3	1.374 (3)	C11—C12	1.365 (5)
O2—C14	1.416 (3)	C11—H11A	0.9300
O3—C21	1.378 (3)	C12—C13	1.381 (5)
O3—H3	0.8727	C12—H12A	0.9300
O3—H3'	0.8599	C13—H13A	0.9300
C1—C2	1.382 (3)	C14—C15	1.496 (4)
C1—C6	1.396 (3)	C14—H14A	0.9700
C2—C3	1.381 (3)	C14—H14B	0.9700
C2—H2A	0.9300	C15—C16	1.372 (4)
C3—C4	1.372 (3)	C15—C20	1.374 (4)
C4—C5	1.394 (3)	C16—C17	1.369 (4)
C4—H4A	0.9300	C16—H16A	0.9300
C5—C6	1.367 (3)	C17—C18	1.349 (5)
C5—C21	1.503 (3)	C17—H17A	0.9300
C6—H6A	0.9300	C18—C19	1.347 (5)
C7—C8	1.494 (4)	C18—H18A	0.9300
C7—H7A	0.9700	C19—C20	1.387 (4)
C7—H7B	0.9700	C19—H19A	0.9300
C8—C13	1.358 (4)	C20—H20A	0.9300
C8—C9	1.369 (4)	C21—H21C	0.9700
C9—C10	1.370 (5)	C21—H21A	0.9700
C9—H9A	0.9300

C1—O1—C7	117.82 (18)	C10—C11—H11A	120.3
C3—O2—C14	117.6 (2)	C12—C11—H11A	120.3
C21—O3—H3	116.4	C11—C12—C13	119.7 (4)
C21—O3—H3'	107.9	C11—C12—H12A	120.1
H3—O3—H3'	103.4	C13—C12—H12A	120.1
O1—C1—C2	124.7 (2)	C8—C13—C12	121.0 (3)
O1—C1—C6	115.0 (2)	C8—C13—H13A	119.5
C2—C1—C6	120.3 (2)	C12—C13—H13A	119.5
C3—C2—C1	118.9 (2)	O2—C14—C15	108.6 (2)
C3—C2—H2A	120.6	O2—C14—H14A	110.0
C1—C2—H2A	120.6	C15—C14—H14A	110.0
C4—C3—O2	124.6 (2)	O2—C14—H14B	110.0
C4—C3—C2	121.2 (2)	C15—C14—H14B	110.0
O2—C3—C2	114.1 (2)	H14A—C14—H14B	108.4
C3—C4—C5	119.7 (2)	C16—C15—C20	117.6 (3)
C3—C4—H4A	120.1	C16—C15—C14	121.4 (3)
C5—C4—H4A	120.1	C20—C15—C14	121.0 (3)
C6—C5—C4	119.8 (2)	C17—C16—C15	120.9 (3)
C6—C5—C21	122.4 (2)	C17—C16—H16A	119.5
C4—C5—C21	117.8 (2)	C15—C16—H16A	119.5
C5—C6—C1	120.1 (2)	C18—C17—C16	121.0 (4)
C5—C6—H6A	119.9	C18—C17—H17A	119.5
C1—C6—H6A	119.9	C16—C17—H17A	119.5
O1—C7—C8	108.02 (19)	C19—C18—C17	119.4 (3)
O1—C7—H7A	110.1	C19—C18—H18A	120.3
C8—C7—H7A	110.1	C17—C18—H18A	120.3
O1—C7—H7B	110.1	C18—C19—C20	120.4 (3)
C8—C7—H7B	110.1	C18—C19—H19A	119.8
H7A—C7—H7B	108.4	C20—C19—H19A	119.8
C13—C8—C9	118.4 (3)	C15—C20—C19	120.6 (3)
C13—C8—C7	120.9 (3)	C15—C20—H20A	119.7
C9—C8—C7	120.8 (3)	C19—C20—H20A	119.7
C8—C9—C10	120.9 (3)	O3—C21—C5	114.2 (2)
C8—C9—H9A	119.6	O3—C21—H21C	108.7
C10—C9—H9A	119.6	C5—C21—H21C	108.7
C11—C10—C9	120.5 (4)	O3—C21—H21A	108.7
C11—C10—H10A	119.8	C5—C21—H21A	108.7
C9—C10—H10A	119.8	H21C—C21—H21A	107.6
C10—C11—C12	119.5 (4)

C7—O1—C1—C2	−4.0 (4)	C7—C8—C9—C10	−178.8 (3)
C7—O1—C1—C6	176.2 (2)	C8—C9—C10—C11	−0.7 (6)
O1—C1—C2—C3	178.9 (2)	C9—C10—C11—C12	0.9 (6)
C6—C1—C2—C3	−1.3 (4)	C10—C11—C12—C13	−1.3 (6)
C14—O2—C3—C4	−10.0 (4)	C9—C8—C13—C12	−1.3 (5)
C14—O2—C3—C2	171.7 (2)	C7—C8—C13—C12	178.3 (3)
C1—C2—C3—C4	0.7 (4)	C11—C12—C13—C8	1.6 (6)
C1—C2—C3—O2	179.1 (2)	C3—O2—C14—C15	−178.2 (2)
O2—C3—C4—C5	−178.4 (2)	O2—C14—C15—C16	83.4 (4)
C2—C3—C4—C5	−0.3 (4)	O2—C14—C15—C20	−96.8 (3)
C3—C4—C5—C6	0.4 (4)	C20—C15—C16—C17	−0.9 (5)
C3—C4—C5—C21	−178.7 (2)	C14—C15—C16—C17	178.9 (3)
C4—C5—C6—C1	−1.0 (4)	C15—C16—C17—C18	0.2 (6)
C21—C5—C6—C1	178.1 (2)	C16—C17—C18—C19	0.6 (6)
O1—C1—C6—C5	−178.8 (2)	C17—C18—C19—C20	−0.7 (5)
C2—C1—C6—C5	1.5 (4)	C16—C15—C20—C19	0.8 (5)
C1—O1—C7—C8	−173.7 (2)	C14—C15—C20—C19	−179.0 (3)
O1—C7—C8—C13	−82.1 (3)	C18—C19—C20—C15	0.0 (5)
O1—C7—C8—C9	97.5 (3)	C6—C5—C21—O3	21.5 (4)
C13—C8—C9—C10	0.9 (5)	C4—C5—C21—O3	−159.4 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O3ⁱ	0.87	1.98	2.791 (4)	155
O3—H3′···O3ⁱⁱ	0.86	1.95	2.805 (5)	179

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

Experimental details

Crystal data
Chemical formula	C₂₁H₂₀O₃
M_r	320.37
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	4.8555 (6), 12.2442 (18), 15.017 (2)
α, β, γ (°)	74.049 (1), 83.293 (1), 89.733 (2)
V (Å³)	852.2 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.46 × 0.16 × 0.15

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.963, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	4355, 2909, 1563
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.168, 0.99
No. of reflections	2909
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.21

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O3ⁱ	0.87	1.98	2.791 (4)	155
O3—H3'···O3ⁱⁱ	0.86	1.95	2.805 (5)	179

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

Acknowledgements

This work was supported by Shandong Province (2007BS02016) and the Key Subject Research Foundation of Shandong Province (XTD 0705).

References

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