2-Hydr­oxy-3-methoxy­benzoic acid monohydrate

Fang, Z.-Q.; Zeng, R.-H.; Yang, M.; Liu, H.; Chen, X.-L.

doi:10.1107/S1600536808006065

organic compounds

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ISSN: 2056-9890

Volume 64| Part 4| April 2008| Page o691

doi:10.1107/S1600536808006065

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2-Hydroxy-3-methoxybenzoic acid monohydrate

Zhan-Qiang Fang,^a ^* Rong-Hua Zeng,^a Mei Yang,^a Hui Liu ^a and Xiao-Lei Chen ^a

^aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China
^*Correspondence e-mail: zhqfang77@yahoo.com.cn

(Received 2 January 2008; accepted 5 March 2008; online 12 March 2008)

The asymmetric unit of the title compound, C₈H₈O₄·H₂O, contains two organic molecules which are connected by the two water molecules through O—H⋯O hydrogen bonds, forming an R₄⁴(12) ring. Further O—H⋯O hydrogen bonds assemble these rings through R₆⁶(18) rings, giving rise to infinite helical chains arranged around the b axis. These helical chains are assembled by offset π–π stacking interactions [centroid–centroid distance = 3.6432 (8) Å] between the aromatic rings of neigboring chains, forming a supramolecular network.

Related literature

For related literature, see: Kozlevcar et al. (2006 ); Moncol et al. (2006 ); Liu et al. (2007 ); Bernstein et al. (1995 ); Etter et al. (1990 ).

Experimental

Crystal data

C₈H₈O₄·H₂O
M_r = 186.16
Monoclinic, P 2₁ /c
a = 17.9642 (4) Å
b = 14.5225 (3) Å
c = 6.8864 (2) Å
β = 91.770 (1)°
V = 1795.70 (8) Å³
Z = 8
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 296 (2) K
0.30 × 0.25 × 0.20 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: none
17337 measured reflections
4111 independent reflections
2658 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.110
S = 1.04
4111 reflections
241 parameters
H-atom parameters constrained
Δρ_max = 0.12 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O3	0.82	1.90	2.6142 (14)	144
O4—H4A⋯O2W	0.82	1.77	2.5634 (16)	164
O5—H5A⋯O1W	0.82	1.78	2.5763 (16)	165
O7—H7⋯O6	0.82	1.88	2.5946 (14)	145
O1W—H1W⋯O3	0.85	1.96	2.8082 (16)	171
O2W—H4W⋯O6	0.85	1.97	2.8071 (16)	170
O1W—H2W⋯O1ⁱ	0.84	2.11	2.8741 (17)	150
O1W—H2W⋯O2ⁱ	0.84	2.49	3.1930 (16)	141
O2W—H3W⋯O8ⁱⁱ	0.84	2.13	2.8866 (19)	149
O2W—H3W⋯O7ⁱⁱ	0.84	2.33	3.0331 (15)	141
Symmetry codes: (i) -x+1, -y+1, -z; (ii) -x+2, -y+1, -z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2003 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808006065/dn2309sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808006065/dn2309Isup2.hkl

checkCIF report

Comment top

Hydrogen-bonding interactions between ligands are specific and directional. In this sense, 2-hydroxy-3-methoxybenzoic acid is an excellent candidate for the construction of supramolecular complexes, which have multiple coordination modes and form regular hydrogen bonds functioning as both a hydrogen-bond donor and acceptor (Kozlevcar et al., 2006, Liu et al., 2007, Moncol et al., 2006). Recently, we obtained the title compound of (I) under hydrothermal condition.

The asymmetric unit of the title compound (I) contains two molecules which are connected by the water molecules trough O—H···O hydrogen bonds building up a R₄⁴(12) ring (Etter et al., 1990; Bernstein et al., 1995) (Table 1, Fig. 1). The C—C and C—O distances ranging from 1.225 (2) to 1.425 (2) Å, show no remarkable features. These rings are further connected to each other by O—H···O hydrogen bonds buiding a R₆⁶ (18) ring to form helical chains arranged around the [0 1/2 0] axis (Table 1, Fig. 2). These helical chains are further assembled through offset π-π stacking interactions between the aromatic rings of neigboring chains (centroid to centroid distance of 3.6432 (8) Å [Symmetry code: 1 - x,1 - y,-1 - z]; interplanar distance of 3.44 Å and slippest distances of 1.20 Å) to form a supramolecular network.

Related literature top

For related literature, see: Kozlevcar et al. (2006); Moncol et al. (2006); Liu et al. (2007); Bernstein et al. (1995); Etter et al. (1990).

Experimental top

2-Hydroxy-3-methoxybenzoic acid was dissolved in hot water with stirring. Colorless single crystals suitable for X-ray diffraction were obtained at room temperature by slow evaporation of the solvent over a period of several days.

Computing details top

Data collection: APEXII (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure showing the atomic-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H bonds are shown as dashed lines. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Partial packing view showing the intermolecular hydrogen bonding interactions as dashed lines. H atoms not involved in hydrogen bondings have been omitted for clarity. [Symmetry codes: (I) 1 - x, 1 - y, -z; (ii) 2 - x, 1 - y, -z]

2-Hydroxy-3-methoxybenzoic acid monohydrate top

Crystal data top

C₈H₈O₄·H₂O	F(000) = 784
M_r = 186.16	D_x = 1.377 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3600 reflections
a = 17.9642 (4) Å	θ = 1.4–28.0°
b = 14.5225 (3) Å	µ = 0.12 mm⁻¹
c = 6.8864 (2) Å	T = 296 K
β = 91.770 (1)°	Block, colorless
V = 1795.70 (8) Å³	0.30 × 0.25 × 0.20 mm
Z = 8

Data collection top

Bruker APEXII area-detector diffractometer	2658 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.026
Graphite monochromator	θ_max = 27.5°, θ_min = 1.1°
ϕ and ω scans	h = −23→23
17337 measured reflections	k = −18→16
4111 independent reflections	l = −8→8

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.110	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0466P)² + 0.2399P] where P = (F_o² + 2F_c²)/3
4111 reflections	(Δ/σ)_max = 0.001
241 parameters	Δρ_max = 0.12 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₈H₈O₄·H₂O	V = 1795.70 (8) Å³
M_r = 186.16	Z = 8
Monoclinic, P2₁/c	Mo Kα radiation
a = 17.9642 (4) Å	µ = 0.12 mm⁻¹
b = 14.5225 (3) Å	T = 296 K
c = 6.8864 (2) Å	0.30 × 0.25 × 0.20 mm
β = 91.770 (1)°

Data collection top

Bruker APEXII area-detector diffractometer	2658 reflections with I > 2σ(I)
17337 measured reflections	R_int = 0.026
4111 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.110	H-atom parameters constrained
S = 1.04	Δρ_max = 0.12 e Å⁻³
4111 reflections	Δρ_min = −0.17 e Å⁻³
241 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
C1	0.32586 (10)	0.67219 (16)	−0.6058 (3)	0.0809 (6)
H1A	0.3210	0.6377	−0.7244	0.121*
H1B	0.3391	0.7346	−0.6347	0.121*
H1C	0.2794	0.6714	−0.5406	0.121*
C2	0.45420 (8)	0.63558 (10)	−0.5448 (2)	0.0460 (4)
C3	0.47543 (9)	0.66626 (11)	−0.7236 (2)	0.0549 (4)
H3	0.4396	0.6869	−0.8138	0.066*
C4	0.54984 (9)	0.66664 (11)	−0.7702 (2)	0.0560 (4)
H4	0.5638	0.6874	−0.8915	0.067*
C5	0.60295 (9)	0.63668 (11)	−0.6385 (2)	0.0515 (4)
H5	0.6528	0.6367	−0.6711	0.062*
C6	0.58266 (8)	0.60588 (10)	−0.4548 (2)	0.0428 (3)
C7	0.50804 (8)	0.60518 (10)	−0.4073 (2)	0.0414 (3)
C8	0.63923 (8)	0.57528 (11)	−0.3100 (2)	0.0498 (4)
C9	0.86646 (8)	0.35192 (11)	0.1597 (2)	0.0455 (4)
C10	0.92233 (7)	0.27809 (10)	0.16407 (19)	0.0399 (3)
C11	0.90153 (9)	0.18508 (10)	0.1659 (2)	0.0498 (4)
H11	0.8514	0.1691	0.1681	0.060*
C12	0.95461 (10)	0.11785 (11)	0.1646 (2)	0.0555 (4)
H12	0.9404	0.0563	0.1647	0.067*
C13	1.02955 (10)	0.14065 (12)	0.1631 (2)	0.0550 (4)
H13	1.0653	0.0943	0.1628	0.066*
C14	1.05131 (8)	0.23114 (11)	0.1620 (2)	0.0464 (4)
C15	0.99746 (8)	0.30129 (10)	0.1617 (2)	0.0400 (3)
C16	1.18105 (11)	0.19618 (16)	0.1478 (4)	0.0897 (7)
H16A	1.1824	0.1585	0.2623	0.135*
H16B	1.2279	0.2272	0.1366	0.135*
H16C	1.1720	0.1582	0.0354	0.135*
O1	0.38246 (5)	0.63195 (9)	−0.48365 (16)	0.0625 (3)
O2	0.48284 (5)	0.57751 (8)	−0.23382 (15)	0.0536 (3)
H2	0.5180	0.5596	−0.1648	0.080*
O3	0.62337 (6)	0.54527 (9)	−0.15029 (17)	0.0642 (3)
O4	0.70797 (6)	0.58220 (11)	−0.36507 (19)	0.0769 (4)
H4A	0.7365	0.5686	−0.2742	0.115*
O5	0.79730 (6)	0.32376 (8)	0.1628 (2)	0.0676 (4)
H5A	0.7694	0.3684	0.1624	0.101*
O6	0.88288 (6)	0.43402 (8)	0.15148 (17)	0.0549 (3)
O7	1.02269 (5)	0.38892 (7)	0.15833 (16)	0.0502 (3)
H7	0.9872	0.4245	0.1510	0.075*
O8	1.12298 (6)	0.26247 (8)	0.16093 (18)	0.0635 (3)
O1W	0.69046 (7)	0.44218 (10)	0.1525 (2)	0.0860 (5)
H1W	0.6738	0.4780	0.0633	0.129*
H2W	0.6557	0.4307	0.2287	0.129*
O2W	0.81581 (7)	0.55507 (10)	−0.1193 (2)	0.0943 (5)
H3W	0.8486	0.5957	−0.1336	0.141*
H4W	0.8309	0.5188	−0.0299	0.141*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0531 (11)	0.1004 (17)	0.0885 (14)	0.0254 (10)	−0.0105 (9)	0.0183 (12)
C2	0.0432 (8)	0.0408 (9)	0.0540 (9)	0.0038 (7)	0.0006 (7)	0.0023 (7)
C3	0.0601 (10)	0.0499 (10)	0.0543 (10)	0.0075 (8)	−0.0055 (8)	0.0082 (8)
C4	0.0676 (11)	0.0505 (10)	0.0502 (9)	−0.0019 (8)	0.0068 (8)	0.0091 (7)
C5	0.0490 (9)	0.0484 (10)	0.0575 (10)	−0.0037 (7)	0.0098 (7)	0.0030 (7)
C6	0.0417 (8)	0.0371 (8)	0.0497 (8)	−0.0026 (6)	0.0019 (6)	0.0015 (6)
C7	0.0440 (8)	0.0338 (8)	0.0464 (8)	−0.0013 (6)	0.0027 (6)	0.0009 (6)
C8	0.0412 (8)	0.0511 (10)	0.0570 (10)	−0.0026 (7)	0.0017 (7)	0.0022 (8)
C9	0.0425 (8)	0.0477 (10)	0.0460 (8)	−0.0029 (7)	−0.0014 (6)	0.0013 (7)
C10	0.0445 (8)	0.0391 (8)	0.0360 (7)	−0.0014 (6)	−0.0006 (6)	0.0010 (6)
C11	0.0559 (9)	0.0446 (10)	0.0486 (9)	−0.0072 (7)	−0.0033 (7)	0.0038 (7)
C12	0.0756 (12)	0.0376 (9)	0.0529 (9)	−0.0016 (8)	−0.0031 (8)	0.0041 (7)
C13	0.0683 (11)	0.0469 (10)	0.0498 (9)	0.0154 (8)	0.0030 (8)	0.0028 (7)
C14	0.0469 (8)	0.0511 (10)	0.0411 (8)	0.0069 (7)	0.0031 (6)	0.0021 (7)
C15	0.0451 (8)	0.0403 (9)	0.0346 (7)	−0.0007 (6)	0.0007 (6)	0.0004 (6)
C16	0.0574 (12)	0.0963 (18)	0.1162 (18)	0.0313 (11)	0.0147 (11)	0.0095 (13)
O1	0.0400 (6)	0.0788 (9)	0.0686 (7)	0.0130 (5)	−0.0003 (5)	0.0157 (6)
O2	0.0429 (6)	0.0693 (8)	0.0487 (6)	0.0036 (5)	0.0049 (5)	0.0124 (5)
O3	0.0484 (6)	0.0880 (9)	0.0562 (7)	0.0054 (6)	−0.0007 (5)	0.0164 (6)
O4	0.0377 (6)	0.1133 (11)	0.0795 (9)	−0.0058 (7)	0.0002 (6)	0.0279 (8)
O5	0.0390 (6)	0.0566 (8)	0.1071 (10)	−0.0032 (5)	−0.0005 (6)	0.0053 (7)
O6	0.0484 (6)	0.0409 (7)	0.0751 (8)	0.0013 (5)	−0.0012 (5)	0.0016 (5)
O7	0.0420 (6)	0.0414 (7)	0.0670 (7)	−0.0031 (5)	0.0010 (5)	−0.0005 (5)
O8	0.0418 (6)	0.0673 (8)	0.0816 (8)	0.0115 (5)	0.0084 (5)	0.0044 (6)
O1W	0.0604 (8)	0.1133 (12)	0.0857 (9)	0.0343 (7)	0.0227 (7)	0.0390 (8)
O2W	0.0522 (7)	0.0961 (11)	0.1329 (13)	−0.0188 (7)	−0.0272 (8)	0.0534 (9)

Geometric parameters (Å, º) top

C1—O1	1.4247 (19)	C10—C11	1.402 (2)
C1—H1A	0.9600	C11—C12	1.365 (2)
C1—H1B	0.9600	C11—H11	0.9300
C1—H1C	0.9600	C12—C13	1.387 (2)
C2—O1	1.3692 (17)	C12—H12	0.9300
C2—C3	1.374 (2)	C13—C14	1.371 (2)
C2—C7	1.4036 (19)	C13—H13	0.9300
C3—C4	1.384 (2)	C14—O8	1.3657 (18)
C3—H3	0.9300	C14—C15	1.405 (2)
C4—C5	1.367 (2)	C15—O7	1.3514 (17)
C4—H4	0.9300	C16—O8	1.425 (2)
C5—C6	1.401 (2)	C16—H16A	0.9600
C5—H5	0.9300	C16—H16B	0.9600
C6—C7	1.3895 (19)	C16—H16C	0.9600
C6—C8	1.470 (2)	O2—H2	0.8200
C7—O2	1.3520 (17)	O4—H4A	0.8200
C8—O3	1.2250 (19)	O5—H5A	0.8200
C8—O4	1.3067 (18)	O7—H7	0.8200
C9—O6	1.2299 (18)	O1W—H1W	0.8516
C9—O5	1.3088 (17)	O1W—H2W	0.8440
C9—C10	1.468 (2)	O2W—H3W	0.8422
C10—C15	1.3916 (19)	O2W—H4W	0.8477

O1—C1—H1A	109.5	C15—C10—C9	119.05 (13)
O1—C1—H1B	109.5	C11—C10—C9	121.44 (13)
H1A—C1—H1B	109.5	C12—C11—C10	120.19 (15)
O1—C1—H1C	109.5	C12—C11—H11	119.9
H1A—C1—H1C	109.5	C10—C11—H11	119.9
H1B—C1—H1C	109.5	C11—C12—C13	120.51 (15)
O1—C2—C3	125.31 (13)	C11—C12—H12	119.7
O1—C2—C7	114.58 (13)	C13—C12—H12	119.7
C3—C2—C7	120.11 (14)	C14—C13—C12	120.39 (15)
C2—C3—C4	120.36 (14)	C14—C13—H13	119.8
C2—C3—H3	119.8	C12—C13—H13	119.8
C4—C3—H3	119.8	O8—C14—C13	126.03 (14)
C5—C4—C3	120.29 (15)	O8—C14—C15	114.06 (14)
C5—C4—H4	119.9	C13—C14—C15	119.91 (14)
C3—C4—H4	119.9	O7—C15—C10	123.65 (13)
C4—C5—C6	120.33 (15)	O7—C15—C14	116.84 (13)
C4—C5—H5	119.8	C10—C15—C14	119.50 (13)
C6—C5—H5	119.8	O8—C16—H16A	109.5
C7—C6—C5	119.62 (13)	O8—C16—H16B	109.5
C7—C6—C8	119.36 (13)	H16A—C16—H16B	109.5
C5—C6—C8	121.01 (13)	O8—C16—H16C	109.5
O2—C7—C6	124.17 (12)	H16A—C16—H16C	109.5
O2—C7—C2	116.55 (13)	H16B—C16—H16C	109.5
C6—C7—C2	119.27 (14)	C2—O1—C1	117.63 (13)
O3—C8—O4	122.41 (14)	C7—O2—H2	109.5
O3—C8—C6	122.77 (14)	C8—O4—H4A	109.5
O4—C8—C6	114.82 (14)	C9—O5—H5A	109.5
O6—C9—O5	122.19 (14)	C15—O7—H7	109.5
O6—C9—C10	122.96 (13)	C14—O8—C16	117.88 (15)
O5—C9—C10	114.85 (14)	H1W—O1W—H2W	108.6
C15—C10—C11	119.49 (13)	H3W—O2W—H4W	108.1

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O3	0.82	1.90	2.6142 (14)	144
O4—H4A···O2W	0.82	1.77	2.5634 (16)	164
O5—H5A···O1W	0.82	1.78	2.5763 (16)	165
O7—H7···O6	0.82	1.88	2.5946 (14)	145
O1W—H1W···O3	0.85	1.96	2.8082 (16)	171
O2W—H4W···O6	0.85	1.97	2.8071 (16)	170
O1W—H2W···O1ⁱ	0.84	2.11	2.8741 (17)	150
O1W—H2W···O2ⁱ	0.84	2.49	3.1930 (16)	141
O2W—H3W···O8ⁱⁱ	0.84	2.13	2.8866 (19)	149
O2W—H3W···O7ⁱⁱ	0.84	2.33	3.0331 (15)	141

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

Experimental details

Crystal data
Chemical formula	C₈H₈O₄·H₂O
M_r	186.16
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	17.9642 (4), 14.5225 (3), 6.8864 (2)
β (°)	91.770 (1)
V (Å³)	1795.70 (8)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	17337, 4111, 2658
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.110, 1.04
No. of reflections	4111
No. of parameters	241
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.12, −0.17

Computer programs: APEXII (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O3	0.82	1.90	2.6142 (14)	144.2
O4—H4A···O2W	0.82	1.77	2.5634 (16)	164.0
O5—H5A···O1W	0.82	1.78	2.5763 (16)	164.7
O7—H7···O6	0.82	1.88	2.5946 (14)	145.0
O1W—H1W···O3	0.85	1.96	2.8082 (16)	170.9
O2W—H4W···O6	0.85	1.97	2.8071 (16)	169.6
O1W—H2W···O1ⁱ	0.84	2.11	2.8741 (17)	150.2
O1W—H2W···O2ⁱ	0.84	2.49	3.1930 (16)	140.9
O2W—H3W···O8ⁱⁱ	0.84	2.13	2.8866 (19)	149.1
O2W—H3W···O7ⁱⁱ	0.84	2.33	3.0331 (15)	140.7

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

Acknowledgements

The authors acknowledge South China Normal University for supporting this work.

References

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