Piperidinium 3-carb­oxy-4-hydroxy­benzene­sulfonate monohydrate

Li, Z.; Cheng, B.; Kunmei, S.

doi:10.1107/S1600536808014256

organic compounds

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ISSN: 2056-9890

Volume 64| Part 6| June 2008| Page o1085

doi:10.1107/S1600536808014256

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Piperidinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate

Zhenhuan Li,^a ^* Bowen Cheng ^a and Su Kunmei ^a

^aCollege of Materials and Chemical Engineering, and Tianjin Key Laboratory of Fiber Modification & Functional Fiber, Tianjin Polytechnic University, Tianjin 300160, People's Republic of China
^*Correspondence e-mail: zhenhuanli1975@yahoo.com.cn

(Received 7 March 2008; accepted 12 May 2008; online 17 May 2008)

The asymmetric unit of the title compound, C₅H₁₂N⁺·C₇H₅O₆S⁻·H₂O, contains a piperidinium cation, one 3-carboxy-4-hydroxybenzenesulfonate anion and one water molecule. Intermolecular O—H⋯O, O—H⋯S and N—H⋯O hydrogen bonds generate a three-dimensional hydrogen-bonded framework.

Related literature

For related literature, see: Smith et al. (2007 ).

Experimental

Crystal data

C₅H₁₂N⁺·C₇H₅O₆S⁻·H₂O
M_r = 321.34
Monoclinic, P 2₁ /n
a = 6.8895 (14) Å
b = 13.202 (3) Å
c = 16.255 (3) Å
β = 93.739 (3)°
V = 1475.3 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.25 mm⁻¹
T = 294 (2) K
0.24 × 0.20 × 0.16 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.942, T_max = 0.961
7480 measured reflections
2602 independent reflections
1966 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.091
S = 1.04
2602 reflections
209 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.26 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O7—H7B⋯O1	0.855 (9)	1.933 (10)	2.786 (2)	176 (2)
O7—H7A⋯O2ⁱ	0.859 (9)	1.912 (10)	2.770 (2)	177 (2)
N1—H1B⋯O5	0.88 (3)	2.55 (2)	2.983 (3)	110.6 (18)
N1—H1B⋯O7ⁱⁱ	0.88 (3)	2.16 (3)	2.996 (3)	157 (2)
N1—H1A⋯O2ⁱⁱⁱ	0.92 (3)	1.90 (3)	2.807 (3)	170 (2)
O6—H6⋯O5	0.84 (3)	1.82 (3)	2.597 (2)	153 (3)
O4—H4⋯O7ⁱⁱ	0.85 (3)	1.75 (3)	2.601 (2)	179 (3)
Symmetry codes: (i) x+1, y, z; (ii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ ; (iii) -x, -y+2, -z+1.

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; 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 I, global. DOI: 10.1107/S1600536808014256/gw2042sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808014256/gw2042Isup2.hkl

checkCIF report

Comment top

5-Sulfosalicylic acid (SSA) has six potential donor sites in the three substituent groups (the sulfonic acid, the carboxylic acid and the phenolic groups), and it gives mono-, di- and trianionic ligand species through deprotonation. The presence of numerous oxygen atoms in the substituent groups usually results in hydrogen-bonding associations, and the self-assembly process of crystallization often requires the incorporation of water molecules in the structures (Smith et al. 2007). We report here the crystal structure of the title compound.

The asymmetric unit of the title compound contains one piperidium cation cation, one 3-carboxyl-4-hydroxyl-benzenesulfonate anion and one water molecule (Fig. 1). The bond distances and angles in the cationic and anionic species are normal. An intramolecular O6—H6···O5 hydrogen bond is observed. The molecular packing (Fig. 2) is stabilized by intermolecular O—H···O, O—H···S and N—H···O hydrogen bonds (Table 1), These interactions generate a three-dimensional hydrogen-bonded framework structure.

Related literature top

For related literature, see: Smith et al. (2007).

Experimental top

2-Hydroxy-5-sulfobenzoic acid (2.18 g, 10 mmol), piperidine (0.85 g, 10 mmol) and H₂O (20 ml) were loaded into a 50 ml roundbottom flask, and heated to dissolve the solid. Crystals of the title compound were obtained by slow evaporation of deionic H₂O solution.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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 asymmteric unit of title compound. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Part of the crystal packing of the title compound. O—H···O and N—H···O hydrogen bonds are shown as dashed lines.

Piperidinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate top

Crystal data top

C₅H₁₂N⁺·C₇H₅O₆S⁻·H₂O	F(000) = 680
M_r = 321.34	D_x = 1.447 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2608 reflections
a = 6.8895 (14) Å	θ = 3.0–25.1°
b = 13.202 (3) Å	µ = 0.25 mm⁻¹
c = 16.255 (3) Å	T = 294 K
β = 93.739 (3)°	Stick, colourless
V = 1475.3 (5) Å³	0.24 × 0.20 × 0.16 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	2602 independent reflections
Radiation source: fine-focus sealed tube	1966 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→8
T_min = 0.942, T_max = 0.961	k = −15→15
7480 measured reflections	l = −19→10

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)] = 0.035	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.091	w = 1/[σ²(F_o²) + (0.0392P)² + 0.5098P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
2602 reflections	Δρ_max = 0.26 e Å⁻³
209 parameters	Δρ_min = −0.28 e Å⁻³
3 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0191 (15)

Crystal data top

C₅H₁₂N⁺·C₇H₅O₆S⁻·H₂O	V = 1475.3 (5) Å³
M_r = 321.34	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 6.8895 (14) Å	µ = 0.25 mm⁻¹
b = 13.202 (3) Å	T = 294 K
c = 16.255 (3) Å	0.24 × 0.20 × 0.16 mm
β = 93.739 (3)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2602 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1966 reflections with I > 2σ(I)
T_min = 0.942, T_max = 0.961	R_int = 0.031
7480 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	3 restraints
wR(F²) = 0.091	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.26 e Å⁻³
2602 reflections	Δρ_min = −0.28 e Å⁻³
209 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
S1	0.16322 (7)	0.89594 (4)	0.24082 (3)	0.03289 (18)
O1	0.3120 (2)	0.93486 (13)	0.19039 (9)	0.0516 (4)
O2	−0.0297 (2)	0.93311 (11)	0.21241 (10)	0.0483 (4)
O3	0.1658 (2)	0.78755 (11)	0.25065 (9)	0.0479 (4)
O4	0.1660 (2)	0.78250 (12)	0.55005 (9)	0.0464 (4)
H4	0.160 (4)	0.752 (2)	0.5956 (17)	0.070*
O5	0.2197 (2)	0.91602 (11)	0.63192 (9)	0.0462 (4)
O6	0.2977 (2)	1.08950 (12)	0.56636 (10)	0.0487 (4)
H6	0.279 (4)	1.044 (2)	0.6018 (17)	0.073*
N1	0.1423 (3)	0.86332 (17)	0.80518 (12)	0.0481 (5)
H1A	0.100 (3)	0.928 (2)	0.7936 (15)	0.058*
H1B	0.124 (4)	0.8238 (18)	0.7615 (16)	0.058*
C1	0.2116 (3)	0.95050 (14)	0.33929 (12)	0.0294 (4)
C2	0.1907 (3)	0.89450 (15)	0.40946 (12)	0.0296 (4)
H2	0.1565	0.8265	0.4050	0.036*
C3	0.2204 (3)	0.93869 (15)	0.48727 (12)	0.0310 (5)
C4	0.2711 (3)	1.04151 (15)	0.49318 (13)	0.0349 (5)
C5	0.2947 (3)	1.09718 (16)	0.42200 (14)	0.0387 (5)
H5	0.3302	1.1651	0.4258	0.046*
C6	0.2656 (3)	1.05223 (15)	0.34626 (13)	0.0365 (5)
H6A	0.2819	1.0899	0.2989	0.044*
C7	0.2020 (3)	0.87879 (16)	0.56285 (13)	0.0345 (5)
C8	0.0182 (4)	0.81764 (19)	0.86596 (17)	0.0630 (8)
H8A	0.0510	0.7466	0.8732	0.076*
H8B	−0.1172	0.8221	0.8458	0.076*
C9	0.0467 (4)	0.8713 (2)	0.94665 (16)	0.0691 (8)
H9A	−0.0299	0.8381	0.9868	0.083*
H9B	0.0008	0.9405	0.9403	0.083*
C10	0.2573 (4)	0.8719 (2)	0.97778 (15)	0.0629 (7)
H10A	0.2722	0.9105	1.0286	0.075*
H10B	0.3002	0.8031	0.9895	0.075*
C11	0.3795 (4)	0.9178 (2)	0.91490 (17)	0.0648 (8)
H11A	0.3461	0.9888	0.9081	0.078*
H11B	0.5154	0.9136	0.9343	0.078*
C12	0.3510 (4)	0.8657 (3)	0.83399 (17)	0.0726 (9)
H12A	0.4242	0.9008	0.7937	0.087*
H12B	0.4002	0.7970	0.8390	0.087*
O7	0.6418 (2)	0.81286 (11)	0.18899 (10)	0.0456 (4)
H7A	0.7460 (19)	0.8483 (15)	0.1972 (16)	0.068*
H7B	0.5375 (18)	0.8480 (15)	0.1880 (17)	0.068*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0357 (3)	0.0317 (3)	0.0308 (3)	0.0030 (2)	−0.0010 (2)	0.0020 (2)
O1	0.0537 (10)	0.0640 (11)	0.0382 (9)	−0.0077 (8)	0.0121 (7)	0.0017 (8)
O2	0.0434 (9)	0.0428 (9)	0.0561 (10)	0.0062 (7)	−0.0162 (7)	−0.0029 (7)
O3	0.0720 (11)	0.0301 (8)	0.0405 (9)	0.0082 (7)	−0.0032 (8)	−0.0010 (7)
O4	0.0677 (11)	0.0385 (9)	0.0334 (9)	−0.0039 (8)	0.0054 (8)	0.0020 (7)
O5	0.0549 (10)	0.0521 (10)	0.0317 (9)	−0.0034 (8)	0.0037 (7)	−0.0078 (7)
O6	0.0595 (10)	0.0418 (10)	0.0445 (10)	−0.0072 (8)	0.0004 (8)	−0.0151 (7)
N1	0.0664 (14)	0.0453 (12)	0.0314 (10)	0.0145 (10)	−0.0064 (9)	−0.0087 (9)
C1	0.0253 (10)	0.0302 (11)	0.0327 (11)	0.0025 (8)	0.0022 (8)	−0.0003 (8)
C2	0.0268 (10)	0.0274 (10)	0.0347 (11)	0.0009 (8)	0.0017 (8)	−0.0035 (9)
C3	0.0243 (10)	0.0347 (11)	0.0340 (11)	0.0017 (8)	0.0014 (8)	−0.0026 (9)
C4	0.0263 (10)	0.0359 (12)	0.0422 (13)	0.0010 (9)	−0.0001 (9)	−0.0102 (10)
C5	0.0363 (12)	0.0291 (11)	0.0507 (14)	−0.0026 (9)	0.0032 (10)	−0.0027 (10)
C6	0.0332 (11)	0.0333 (12)	0.0430 (13)	0.0007 (9)	0.0034 (9)	0.0043 (10)
C7	0.0276 (11)	0.0398 (13)	0.0361 (12)	0.0019 (9)	0.0030 (9)	−0.0046 (10)
C8	0.0621 (17)	0.0474 (15)	0.0756 (19)	−0.0215 (13)	−0.0251 (14)	0.0167 (13)
C9	0.0687 (19)	0.092 (2)	0.0485 (16)	−0.0086 (16)	0.0178 (14)	0.0167 (15)
C10	0.082 (2)	0.0681 (18)	0.0357 (14)	−0.0133 (15)	−0.0139 (13)	0.0039 (12)
C11	0.0533 (16)	0.0748 (19)	0.0635 (18)	−0.0191 (14)	−0.0169 (13)	0.0147 (14)
C12	0.0524 (17)	0.107 (2)	0.0592 (18)	0.0259 (16)	0.0114 (13)	0.0104 (16)
O7	0.0447 (9)	0.0437 (9)	0.0486 (10)	−0.0015 (7)	0.0040 (8)	−0.0046 (7)

Geometric parameters (Å, º) top

S1—O3	1.4398 (15)	C5—C6	1.370 (3)
S1—O1	1.4478 (16)	C5—H5	0.9300
S1—O2	1.4628 (15)	C6—H6A	0.9300
S1—C1	1.767 (2)	C8—C9	1.492 (4)
O4—C7	1.309 (3)	C8—H8A	0.9700
O4—H4	0.85 (3)	C8—H8B	0.9700
O5—C7	1.224 (2)	C9—C10	1.505 (4)
O6—C4	1.350 (2)	C9—H9A	0.9700
O6—H6	0.84 (3)	C9—H9B	0.9700
N1—C8	1.477 (3)	C10—C11	1.494 (4)
N1—C12	1.483 (3)	C10—H10A	0.9700
N1—H1A	0.92 (3)	C10—H10B	0.9700
N1—H1B	0.88 (3)	C11—C12	1.485 (4)
C1—C2	1.375 (3)	C11—H11A	0.9700
C1—C6	1.396 (3)	C11—H11B	0.9700
C2—C3	1.396 (3)	C12—H12A	0.9700
C2—H2	0.9300	C12—H12B	0.9700
C3—C4	1.403 (3)	O7—H7A	0.859 (9)
C3—C7	1.473 (3)	O7—H7B	0.855 (9)
C4—C5	1.389 (3)

O3—S1—O1	114.30 (10)	O5—C7—C3	122.69 (19)
O3—S1—O2	111.89 (9)	O4—C7—C3	114.48 (18)
O1—S1—O2	111.36 (10)	N1—C8—C9	110.2 (2)
O3—S1—C1	107.72 (9)	N1—C8—H8A	109.6
O1—S1—C1	105.64 (9)	C9—C8—H8A	109.6
O2—S1—C1	105.25 (9)	N1—C8—H8B	109.6
C7—O4—H4	109.9 (19)	C9—C8—H8B	109.6
C4—O6—H6	105 (2)	H8A—C8—H8B	108.1
C8—N1—C12	112.9 (2)	C8—C9—C10	111.5 (2)
C8—N1—H1A	109.1 (15)	C8—C9—H9A	109.3
C12—N1—H1A	109.4 (16)	C10—C9—H9A	109.3
C8—N1—H1B	103.9 (16)	C8—C9—H9B	109.3
C12—N1—H1B	110.4 (16)	C10—C9—H9B	109.3
H1A—N1—H1B	111 (2)	H9A—C9—H9B	108.0
C2—C1—C6	119.45 (18)	C11—C10—C9	110.2 (2)
C2—C1—S1	120.57 (15)	C11—C10—H10A	109.6
C6—C1—S1	119.95 (15)	C9—C10—H10A	109.6
C1—C2—C3	120.67 (18)	C11—C10—H10B	109.6
C1—C2—H2	119.7	C9—C10—H10B	109.6
C3—C2—H2	119.7	H10A—C10—H10B	108.1
C2—C3—C4	119.16 (18)	C12—C11—C10	111.7 (2)
C2—C3—C7	121.05 (18)	C12—C11—H11A	109.3
C4—C3—C7	119.78 (18)	C10—C11—H11A	109.3
O6—C4—C5	117.99 (18)	C12—C11—H11B	109.3
O6—C4—C3	122.22 (19)	C10—C11—H11B	109.3
C5—C4—C3	119.79 (19)	H11A—C11—H11B	107.9
C6—C5—C4	120.09 (19)	N1—C12—C11	111.0 (2)
C6—C5—H5	120.0	N1—C12—H12A	109.4
C4—C5—H5	120.0	C11—C12—H12A	109.4
C5—C6—C1	120.8 (2)	N1—C12—H12B	109.4
C5—C6—H6A	119.6	C11—C12—H12B	109.4
C1—C6—H6A	119.6	H12A—C12—H12B	108.0
O5—C7—O4	122.83 (19)	H7A—O7—H7B	113.6 (15)

O3—S1—C1—C2	−17.95 (18)	C3—C4—C5—C6	1.0 (3)
O1—S1—C1—C2	−140.49 (16)	C4—C5—C6—C1	0.2 (3)
O2—S1—C1—C2	101.57 (16)	C2—C1—C6—C5	−1.1 (3)
O3—S1—C1—C6	164.09 (15)	S1—C1—C6—C5	176.88 (15)
O1—S1—C1—C6	41.55 (18)	C2—C3—C7—O5	−177.13 (18)
O2—S1—C1—C6	−76.39 (17)	C4—C3—C7—O5	3.7 (3)
C6—C1—C2—C3	0.9 (3)	C2—C3—C7—O4	3.2 (3)
S1—C1—C2—C3	−177.12 (14)	C4—C3—C7—O4	−175.97 (18)
C1—C2—C3—C4	0.3 (3)	C12—N1—C8—C9	55.3 (3)
C1—C2—C3—C7	−178.85 (17)	N1—C8—C9—C10	−55.7 (3)
C2—C3—C4—O6	178.52 (17)	C8—C9—C10—C11	56.0 (3)
C7—C3—C4—O6	−2.3 (3)	C9—C10—C11—C12	−55.3 (3)
C2—C3—C4—C5	−1.2 (3)	C8—N1—C12—C11	−54.9 (3)
C7—C3—C4—C5	177.93 (17)	C10—C11—C12—N1	54.5 (3)
O6—C4—C5—C6	−178.76 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O7—H7B···O1	0.86 (1)	1.93 (1)	2.786 (2)	176 (2)
O7—H7A···O2ⁱ	0.86 (1)	1.91 (1)	2.770 (2)	177 (2)
N1—H1B···O5	0.88 (3)	2.55 (2)	2.983 (3)	110.6 (18)
N1—H1B···O7ⁱⁱ	0.88 (3)	2.16 (3)	2.996 (3)	157 (2)
N1—H1A···O2ⁱⁱⁱ	0.92 (3)	1.90 (3)	2.807 (3)	170 (2)
O6—H6···O5	0.84 (3)	1.82 (3)	2.597 (2)	153 (3)
O4—H4···O7ⁱⁱ	0.85 (3)	1.75 (3)	2.601 (2)	179 (3)

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

Experimental details

Crystal data
Chemical formula	C₅H₁₂N⁺·C₇H₅O₆S⁻·H₂O
M_r	321.34
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	294
a, b, c (Å)	6.8895 (14), 13.202 (3), 16.255 (3)
β (°)	93.739 (3)
V (Å³)	1475.3 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.25
Crystal size (mm)	0.24 × 0.20 × 0.16

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.942, 0.961
No. of measured, independent and observed [I > 2σ(I)] reflections	7480, 2602, 1966
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.091, 1.04
No. of reflections	2602
No. of parameters	209
No. of restraints	3
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.26, −0.28

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), 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
O7—H7B···O1	0.855 (9)	1.933 (10)	2.786 (2)	176 (2)
O7—H7A···O2ⁱ	0.859 (9)	1.912 (10)	2.770 (2)	177 (2)
N1—H1B···O5	0.88 (3)	2.55 (2)	2.983 (3)	110.6 (18)
N1—H1B···O7ⁱⁱ	0.88 (3)	2.16 (3)	2.996 (3)	157 (2)
N1—H1A···O2ⁱⁱⁱ	0.92 (3)	1.90 (3)	2.807 (3)	170 (2)
O6—H6···O5	0.84 (3)	1.82 (3)	2.597 (2)	153 (3)
O4—H4···O7ⁱⁱ	0.85 (3)	1.75 (3)	2.601 (2)	179 (3)

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

Acknowledgements

The authors are grateful for the financial support of Tianjin Polytechnic University (029623 and 029817) and the Natural Science Foundation of Tianjin Education Committee (20070607).

References

Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Smith, G., Wermuth, U. D., Young, D. J. & White, J. M. (2007). Polyhedron, 26, 3645–3652. Web of Science CSD CrossRef CAS Google Scholar