Poly[[diaqua­bis­(μ-oxalato-κ4O1,O2:O1′,O2′)bis­(μ3-5-oxidopyridin-1-ium-3-carboxyl­ato-κ3O3:O3′:O5)diholmium(III)] dihydrate]

Mi, J.-L.; Huang, J.; Chen, H.-J.

doi:10.1107/S1600536812032916

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Pages m1146-m1147

doi:10.1107/S1600536812032916

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Poly[[diaquabis(μ-oxalato-κ⁴O¹,O²:O^1′,O^2′)bis(μ₃-5-oxidopyridin-1-ium-3-carboxylato-κ³O³:O^3′:O⁵)diholmium(III)] dihydrate]

Jun-Long Mi,^a Jing Huang ^a and Hong-Ji Chen ^a ^*

^aDepartment of Materials Science and Engineering, Jinan University, Guangzhou 510632, People's Republic of China
^*Correspondence e-mail: thjchen@jnu.edu.cn

(Received 26 June 2012; accepted 20 July 2012; online 4 August 2012)

In the title compound, {[Ho₂(C₆H₄NO₃)₂(C₂O₄)₂(H₂O)₂]·2H₂O}_n, the Ho^III atom is coordinated by three O atoms from three 5-hydroxynicotinate ligands, four O atoms from two oxalate ligands, each lying on an inversion center, and one water molecule in a distorted square-antiprismatic geometry. The 5-hydroxynicotinate ligand is protonated at the N atom and deprotonated at the hydroxy group. The Ho^III atoms are bridged by the carboxylate and phenolate O atoms, forming a three-dimensional framework. N—H⋯O and O—H⋯O hydrogen bonds, as well as π–π interactions between the pyridine rings [centroid–centroid distance = 3.794 (2) Å], are observed.

Related literature

For background to the applications of compounds with metal-organic framework structures, see: Allendorf et al. (2009 ); Choi et al. (2008 ); Dang et al. (2010 ); Ishikawa et al. (2005 ); Lazare et al. (2010 ); Shimomura et al. (2010 ); Thallapally et al. (2010 ). For related structures, see: Zhang et al. (2012 ).

Experimental

Crystal data

[Ho₂(C₆H₄NO₃)₂(C₂O₄)₂(H₂O)₂]·2H₂O
M_r = 854.16
Triclinic, $[P \overline 1]$
a = 7.7786 (16) Å
b = 8.0562 (17) Å
c = 9.505 (2) Å
α = 110.912 (3)°
β = 96.862 (3)°
γ = 95.770 (3)°
V = 545.8 (2) Å³
Z = 1
Mo Kα radiation
μ = 7.30 mm⁻¹
T = 173 K
0.18 × 0.16 × 0.06 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.354, T_max = 0.669
4550 measured reflections
2295 independent reflections
2160 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.016
wR(F²) = 0.038
S = 1.05
2295 reflections
192 parameters
5 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.57 e Å⁻³
Δρ_min = −0.49 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O7ⁱ	0.90 (1)	1.83 (1)	2.727 (3)	171 (3)
O8—H7⋯O9ⁱⁱ	0.85 (1)	1.95 (1)	2.787 (4)	171 (5)
O8—H8⋯O4ⁱⁱⁱ	0.85 (1)	1.96 (1)	2.811 (3)	177 (6)
O9—H9⋯O3^iv	0.85 (1)	2.08 (1)	2.929 (4)	178 (6)
O9—H10⋯O1ⁱⁱ	0.85 (1)	2.48 (6)	3.003 (4)	120 (5)
Symmetry codes: (i) -x+2, -y+2, -z+1; (ii) -x+1, -y+2, -z+1; (iii) -x+1, -y+2, -z+2; (iv) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812032916/hy2567sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812032916/hy2567Isup2.hkl

checkCIF report

Comment top

Metal-organic frameworks (MOFs) remain nowadays one of the most studied topics in synthetic chemistry due to MOFs hold interesting structural features and properties. For example, they can be employed as effective heterogeneous catalysts (Dang et al., 2010; Lazare et al., 2010; Thallapally et al., 2010), selective adsorption of gases (Choi et al., 2008; Shimomura et al., 2010), photoluminescent (Allendorf et al., 2009) and magnetic properties (Ishikawa et al., 2005).

The title compound is isostructural with its Dy(III) and Er(III) analogues (Zhang et al., 2012). As shown in Fig. 1, the asymmetric unit is composed of one Ho^III atom, one phenoxonicotinate ligand, two halfs of oxalate ligands, one coordinated and one solvent water molecules. The Ho^III atom is coordinated by eight O atoms, exhibiting a distorted square-antiprismatic geometry. One basal square face of the antiprism is defined by two carboxylate O atoms, one oxalate O atom and one aqua O atom; the other base is completed by the other three oxalate O atoms and one phenolate O atom. Adjacent Ho^III atoms are bonded to the carboxylate and phenolate O atoms of the phenoxonicotinate ligand, forming dinuclear subunits, which are further extented at a syn-anti conformation into infinite ladder-like chains. The metal atoms are also bridged by oxalate ligands in a side-by-side manner, forming one-dimensional zigzag chains. Both the ladder-like and zigzag chains are finally linked together through the metal atoms into a three-dimensional framework with one-dimensional microchannels (Fig. 2). The three-dimensional framework shows a topology of 3,5-connected {4².6⁵.8³}.{4².6} (Fig. 3). N—H···O and O—H···O hydrogen bonds, as well as π–π interactions between the pyridine rings [centroid–centroid distance = 3.794 (2)Å] are found in the crystal.

Related literature top

For background to the applications of compounds with metal-organic framework structures, see: Allendorf et al. (2009); Choi et al. (2008); Dang et al. (2010); Ishikawa et al. (2005); Lazare et al. (2010); Shimomura et al. (2010); Thallapally et al. (2010). For related structures, see: Zhang et al. (2012).

Experimental top

A mixture of holmium nitrate (0.4 mmol, 0.181 g), 5-hydroxynicotinic acid (0.8 mmol, 0.111 g), ammonium oxalate (0.8 mmol, 0.099 g) and 10 ml water was sealed in a 15 ml Teflon-lined autoclave. Colorless crystals suitable for X-ray crystallography analysis were obtained by heating the mixture at 453 K for 72 h and then cooled down to room temperature at a rate of 5 K h^-1 (yield: 41%). Analysis, calculated for C₁₆H₁₆Ho₂N₂O₁₈: C 22.50, H 1.89, N 3.28%; found: C 22.65, H 1.91, N 3.13%. IR (cm^-1, KBr): 3398 s, 3083 s, 2957 m, 2768 w, 2089 w, 1900 w, 1646 m, 1565 m, 1447 w, 1427 w, 1359 s, 1319 s, 1302 s, 1140 s, 1051 s, 1013 s, 963 s, 942 m, 894 w, 865 w, 823 w, 788 w, 672 m, 591 s, 545 s, 497 m, 450 w, 413 w.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The asymmetric unit of the title compound, showing displacement ellipsoids at the 50% probability level. [Symmetry codes: (i) 1-x, 2-y, 1-z; (ii) 2-x, 2-y, 2-z; (iii) 1-x, 1-y, 1-z; (iv) x, -1+y, -1+z.]
	Fig. 2. The three-dimensional framework of the title compound. H atoms and solvent water molecules are omitted for clarity.
	Fig. 3. A schematic view of the three-dimensional framework for the title compound.

Poly[[diaquabis(µ-oxalato- κ⁴O¹,O²:O^1',O^2')bis(µ₃-5- oxidopyridin-1-ium-3-carboxylato- κ³O³:O^3':O⁵)diholmium(III)] dihydrate] top

Crystal data top

[Ho₂(C₆H₄NO₃)₂(C₂O₄)₂(H₂O)₂]·2H₂O	Z = 1
M_r = 854.16	F(000) = 404
Triclinic, P1	D_x = 2.599 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.7786 (16) Å	Cell parameters from 4550 reflections
b = 8.0562 (17) Å	θ = 2.3–27.0°
c = 9.505 (2) Å	µ = 7.30 mm⁻¹
α = 110.912 (3)°	T = 173 K
β = 96.862 (3)°	Block, colorless
γ = 95.770 (3)°	0.18 × 0.16 × 0.06 mm
V = 545.8 (2) Å³

Data collection top

Bruker APEXII CCD diffractometer	2295 independent reflections
Radiation source: fine-focus sealed tube	2160 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 27.0°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
T_min = 0.354, T_max = 0.669	k = −10→10
4550 measured reflections	l = −12→12

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)] = 0.016	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.038	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.016P)² + 0.6363P] where P = (F_o² + 2F_c²)/3
2295 reflections	(Δ/σ)_max = 0.001
192 parameters	Δρ_max = 0.57 e Å⁻³
5 restraints	Δρ_min = −0.49 e Å⁻³

Crystal data top

[Ho₂(C₆H₄NO₃)₂(C₂O₄)₂(H₂O)₂]·2H₂O	γ = 95.770 (3)°
M_r = 854.16	V = 545.8 (2) Å³
Triclinic, P1	Z = 1
a = 7.7786 (16) Å	Mo Kα radiation
b = 8.0562 (17) Å	µ = 7.30 mm⁻¹
c = 9.505 (2) Å	T = 173 K
α = 110.912 (3)°	0.18 × 0.16 × 0.06 mm
β = 96.862 (3)°

Data collection top

Bruker APEXII CCD diffractometer	2295 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2160 reflections with I > 2σ(I)
T_min = 0.354, T_max = 0.669	R_int = 0.017
4550 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.016	5 restraints
wR(F²) = 0.038	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.57 e Å⁻³
2295 reflections	Δρ_min = −0.49 e Å⁻³
192 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	0.6934 (4)	1.2898 (4)	1.1270 (3)	0.0109 (5)
C2	0.7746 (4)	0.4547 (4)	0.2648 (3)	0.0123 (6)
C3	0.7041 (4)	0.5062 (4)	0.3987 (3)	0.0117 (6)
H3	0.5989	0.4387	0.4032	0.014*
C4	0.7864 (4)	0.6576 (4)	0.5285 (3)	0.0124 (6)
C5	0.9393 (4)	0.7518 (4)	0.5123 (3)	0.0158 (6)
H5	0.9999	0.8543	0.5962	0.019*
C6	0.9258 (4)	0.5562 (4)	0.2565 (4)	0.0162 (6)
H6	0.9743	0.5245	0.1651	0.019*
C7	0.9532 (4)	0.9560 (4)	1.0490 (3)	0.0106 (6)
C8	0.4187 (4)	0.9302 (4)	0.4887 (3)	0.0116 (6)
Ho1	0.647369 (16)	0.971506 (16)	0.803507 (14)	0.00854 (5)
N1	1.0014 (3)	0.6993 (4)	0.3802 (3)	0.0168 (5)
O1	0.7614 (3)	1.2593 (3)	1.0082 (2)	0.0162 (5)
O2	0.4346 (3)	0.8128 (3)	0.8643 (2)	0.0136 (4)
O3	0.7231 (3)	0.7072 (3)	0.6565 (2)	0.0150 (4)
O4	0.7922 (3)	0.8943 (3)	1.0004 (2)	0.0133 (4)
O5	0.9595 (3)	1.0464 (3)	0.8342 (2)	0.0123 (4)
O6	0.4182 (3)	0.8477 (3)	0.5761 (2)	0.0161 (4)
O7	0.7033 (3)	1.0868 (3)	0.6190 (2)	0.0135 (4)
O8	0.4335 (3)	1.1739 (3)	0.8101 (3)	0.0197 (5)
O9	0.3549 (5)	0.5133 (4)	0.1651 (4)	0.0462 (8)
H1	1.102 (3)	0.760 (4)	0.373 (4)	0.011 (8)*
H7	0.489 (6)	1.275 (4)	0.822 (6)	0.061 (17)*
H8	0.363 (6)	1.155 (7)	0.866 (5)	0.065 (17)*
H9	0.331 (8)	0.448 (7)	0.216 (6)	0.08 (2)*
H10	0.269 (6)	0.501 (9)	0.096 (5)	0.09 (2)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0095 (13)	0.0105 (13)	0.0124 (14)	0.0018 (10)	0.0013 (10)	0.0039 (11)
C2	0.0128 (14)	0.0109 (14)	0.0113 (14)	0.0000 (11)	0.0015 (11)	0.0027 (11)
C3	0.0087 (14)	0.0118 (14)	0.0147 (14)	0.0008 (10)	0.0034 (11)	0.0046 (11)
C4	0.0136 (14)	0.0110 (14)	0.0126 (14)	0.0038 (11)	0.0029 (11)	0.0037 (11)
C5	0.0135 (15)	0.0159 (15)	0.0141 (15)	−0.0008 (11)	0.0017 (11)	0.0020 (12)
C6	0.0149 (15)	0.0161 (15)	0.0143 (15)	−0.0008 (12)	0.0039 (11)	0.0020 (12)
C7	0.0123 (14)	0.0095 (13)	0.0088 (13)	0.0042 (11)	0.0022 (10)	0.0012 (11)
C8	0.0096 (14)	0.0128 (14)	0.0115 (14)	0.0002 (11)	0.0017 (10)	0.0038 (11)
Ho1	0.00804 (7)	0.00981 (7)	0.00735 (7)	−0.00004 (5)	−0.00004 (4)	0.00353 (5)
N1	0.0126 (13)	0.0181 (13)	0.0151 (13)	−0.0051 (10)	0.0041 (10)	0.0022 (11)
O1	0.0163 (11)	0.0151 (11)	0.0127 (10)	−0.0024 (8)	0.0061 (8)	−0.0002 (9)
O2	0.0108 (10)	0.0137 (10)	0.0141 (10)	−0.0019 (8)	−0.0005 (8)	0.0045 (8)
O3	0.0173 (11)	0.0149 (10)	0.0106 (10)	0.0019 (8)	0.0050 (8)	0.0015 (8)
O4	0.0108 (10)	0.0185 (11)	0.0109 (10)	0.0007 (8)	0.0001 (8)	0.0069 (8)
O5	0.0105 (10)	0.0159 (10)	0.0101 (10)	0.0012 (8)	0.0004 (8)	0.0052 (8)
O6	0.0170 (11)	0.0165 (11)	0.0148 (11)	−0.0054 (8)	−0.0047 (8)	0.0103 (9)
O7	0.0108 (10)	0.0189 (11)	0.0115 (10)	−0.0019 (8)	−0.0010 (8)	0.0086 (8)
O8	0.0220 (13)	0.0232 (13)	0.0201 (12)	0.0096 (10)	0.0087 (9)	0.0122 (10)
O9	0.056 (2)	0.0259 (15)	0.055 (2)	0.0023 (14)	−0.0118 (17)	0.0206 (15)

Geometric parameters (Å, º) top

C1—O2ⁱ	1.259 (4)	C8—O6	1.235 (4)
C1—O1	1.260 (4)	C8—O7^v	1.269 (3)
C1—C2ⁱⁱ	1.507 (4)	C8—C8^v	1.545 (6)
C2—C3	1.388 (4)	Ho1—O2	2.245 (2)
C2—C6	1.390 (4)	Ho1—O3	2.271 (2)
C2—C1ⁱⁱⁱ	1.507 (4)	Ho1—O7	2.322 (2)
C3—C4	1.414 (4)	Ho1—O4	2.372 (2)
C3—H3	0.9500	Ho1—O5	2.399 (2)
C4—O3	1.311 (4)	Ho1—O1	2.429 (2)
C4—C5	1.400 (4)	Ho1—O8	2.435 (2)
C5—N1	1.340 (4)	Ho1—O6	2.455 (2)
C5—H5	0.9500	N1—H1	0.90 (1)
C6—N1	1.337 (4)	O8—H7	0.85 (1)
C6—H6	0.9500	O8—H8	0.85 (1)
C7—O5^iv	1.237 (3)	O9—H9	0.85 (1)
C7—O4	1.266 (4)	O9—H10	0.85 (1)
C7—C7^iv	1.559 (6)

O2ⁱ—C1—O1	123.0 (3)	O4—Ho1—O5	68.67 (7)
O2ⁱ—C1—C2ⁱⁱ	119.6 (3)	O2—Ho1—O1	112.36 (7)
O1—C1—C2ⁱⁱ	117.4 (3)	O3—Ho1—O1	143.48 (8)
C3—C2—C6	119.6 (3)	O7—Ho1—O1	91.68 (7)
C3—C2—C1ⁱⁱⁱ	122.1 (3)	O4—Ho1—O1	75.80 (7)
C6—C2—C1ⁱⁱⁱ	118.3 (3)	O5—Ho1—O1	67.35 (7)
C2—C3—C4	121.0 (3)	O2—Ho1—O8	83.88 (8)
C2—C3—H3	119.5	O3—Ho1—O8	142.95 (8)
C4—C3—H3	119.5	O7—Ho1—O8	75.53 (8)
O3—C4—C5	121.8 (3)	O4—Ho1—O8	130.78 (7)
O3—C4—C3	122.0 (3)	O5—Ho1—O8	126.55 (8)
C5—C4—C3	116.2 (3)	O1—Ho1—O8	71.62 (8)
N1—C5—C4	120.9 (3)	O2—Ho1—O6	74.25 (7)
N1—C5—H5	119.5	O3—Ho1—O6	74.55 (8)
C4—C5—H5	119.5	O7—Ho1—O6	68.06 (7)
N1—C6—C2	118.5 (3)	O4—Ho1—O6	141.48 (7)
N1—C6—H6	120.7	O5—Ho1—O6	132.12 (7)
C2—C6—H6	120.7	O1—Ho1—O6	138.53 (7)
O5^iv—C7—O4	126.2 (3)	O8—Ho1—O6	68.47 (8)
O5^iv—C7—C7^iv	118.1 (3)	C6—N1—C5	123.8 (3)
O4—C7—C7^iv	115.7 (3)	C6—N1—H1	117 (2)
O6—C8—O7^v	126.3 (3)	C5—N1—H1	119 (2)
O6—C8—C8^v	118.0 (3)	C1—O1—Ho1	115.09 (18)
O7^v—C8—C8^v	115.6 (3)	C1ⁱ—O2—Ho1	169.7 (2)
O2—Ho1—O3	88.38 (8)	C4—O3—Ho1	132.61 (19)
O2—Ho1—O7	141.51 (7)	C7—O4—Ho1	118.19 (18)
O3—Ho1—O7	88.96 (8)	C7^iv—O5—Ho1	116.85 (18)
O2—Ho1—O4	75.56 (7)	C8—O6—Ho1	115.09 (18)
O3—Ho1—O4	81.26 (8)	C8^v—O7—Ho1	119.68 (18)
O7—Ho1—O4	141.63 (7)	Ho1—O8—H7	108 (4)
O2—Ho1—O5	143.17 (7)	Ho1—O8—H8	106 (4)
O3—Ho1—O5	78.02 (7)	H7—O8—H8	126 (5)
O7—Ho1—O5	73.02 (7)	H9—O9—H10	111 (6)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O7^vi	0.90 (1)	1.83 (1)	2.727 (3)	171 (3)
O8—H7···O9^v	0.85 (1)	1.95 (1)	2.787 (4)	171 (5)
O8—H8···O4ⁱ	0.85 (1)	1.96 (1)	2.811 (3)	177 (6)
O9—H9···O3^vii	0.85 (1)	2.08 (1)	2.929 (4)	178 (6)
O9—H10···O1^v	0.85 (1)	2.48 (6)	3.003 (4)	120 (5)

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

Experimental details

Crystal data
Chemical formula	[Ho₂(C₆H₄NO₃)₂(C₂O₄)₂(H₂O)₂]·2H₂O
M_r	854.16
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	7.7786 (16), 8.0562 (17), 9.505 (2)
α, β, γ (°)	110.912 (3), 96.862 (3), 95.770 (3)
V (Å³)	545.8 (2)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	7.30
Crystal size (mm)	0.18 × 0.16 × 0.06

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.354, 0.669
No. of measured, independent and observed [I > 2σ(I)] reflections	4550, 2295, 2160
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.639

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.016, 0.038, 1.05
No. of reflections	2295
No. of parameters	192
No. of restraints	5
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.57, −0.49

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O7ⁱ	0.90 (1)	1.83 (1)	2.727 (3)	171 (3)
O8—H7···O9ⁱⁱ	0.85 (1)	1.95 (1)	2.787 (4)	171 (5)
O8—H8···O4ⁱⁱⁱ	0.85 (1)	1.96 (1)	2.811 (3)	177 (6)
O9—H9···O3^iv	0.85 (1)	2.08 (1)	2.929 (4)	178 (6)
O9—H10···O1ⁱⁱ	0.85 (1)	2.48 (6)	3.003 (4)	120 (5)

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

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