catena-Poly[[bis­(4-carboxy­cyclo­hexane­carboxyl­ato-κ2O1,O1′)cadmium(II)]-μ-1,4-bis­(imidazol-1-ylmeth­yl)benzene-κ2N3:N3′]

Li, B.-B.; Xiao, B.

doi:10.1107/S1600536809021618

metal-organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 7| July 2009| Pages m756-m757

doi:10.1107/S1600536809021618

Open

access

catena-Poly[[bis(4-carboxycyclohexanecarboxylato-κ²O¹,O^1′)cadmium(II)]-μ-1,4-bis(imidazol-1-ylmethyl)benzene-κ²N³:N^3′]

Bing-Bing Li ^a,^b ^* and Bo Xiao ^a

^aSchool of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China, and ^bDepartment of Bioengineering, Henan University of Urban Construction, Pingdingshan 467000, People's Republic of China
^*Correspondence e-mail: libingbinghncj@yahoo.com.cn

(Received 25 May 2009; accepted 7 June 2009; online 10 June 2009)

In the title coordination polymer, [Cd(C₈H₁₁O₄)₂(C₁₄H₁₄N₄)]_n, the Cd atom (site symmetry 2) is six-coordinated by two O,O′-bidentate 4-carboxycyclohexanecarboxylate (Hchdc) ligands and two N atoms from two different 1,4-bis(imidazol-1-ylmethyl)benzene (1,4-bix) molecules in a very distorted cis-CdN₂O₄ octahedral environment. The 1,4-bix molecules act as bridging ligands that bind two Cd^II atoms, thus forming an infinite chain propagating in [100], which is decorated by the Hchdc anions. The structure is completed by O—H⋯O hydrogen bonds, which link the chains together.

Related literature

For related structures, see: Qi et al. (2003 ). For background to coordination polymers, see: Chen & Liu (2002 ); Fang et al. (2006 ); Kim & Jung (2002 ); Lehn (1990 ); Batten & Robson (1998 ); Yang et al. (2008 ).

Experimental

Crystal data

[Cd(C₈H₁₁O₄)₂(C₁₄H₁₄N₄)]
M_r = 693.03
Orthorhombic, P c c n
a = 12.6317 (5) Å
b = 19.9697 (12) Å
c = 12.3703 (7) Å
V = 3120.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.75 mm⁻¹
T = 292 K
0.26 × 0.22 × 0.17 mm

Data collection

Oxford Diffraction Gemini R Ultra diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.816, T_max = 0.882
26676 measured reflections
3190 independent reflections
1658 reflections with I > 2σ(I)
R_int = 0.116

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.120
S = 0.95
3190 reflections
195 parameters
H-atom parameters constrained
Δρ_max = 0.62 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Cd1—N1	2.249 (4)
Cd1—O1	2.306 (4)
Cd1—O2	2.384 (4)

O1—Cd1—O2	55.00 (14)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H4⋯O2ⁱ	0.82	1.86	2.644 (6)	161
Symmetry code: (i) $[x+{\script{1\over 2}}, -y, -z+{\script{1\over 2}}]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809021618/hb2986sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809021618/hb2986Isup2.hkl

checkCIF report

Comment top

The rational design and synthesis of metal-organic coordination polymers have received intense interest due to their fascinating structural topologies and potential applications as functional materials (e.g. Fang et al., 2006). These coordination polymers can be specially designed by the careful selection of metal cations with preferred coordination geometries, the nature of the anions, the structure of the connecting ligands, and the reaction conditions (Kim & Jung, 2002). The selection of ligand is extremely important because changing the structures of the ligands can control and adjust the topologies of coordination frameworks. Among these mentioned above, chain structures have received much attention in coordination chemistry and life sciecnce (Lehn, 1990). So far, many chain complexes have been generated by self-assembly processes (Chen & Liu, 2002). In this regard, metal 1,4-benzenedicarboxylates (1,4-bdc) have been widely studied (Qi et al., 2003). However, so far, less attention has been given to the 1,4-cyclohexanedicarboxylic acid ligand (H₂chdc). The H₂chdc as an important analogues of 1,4-bdc may be a good candidate for the construction of metal-organic architectures. On the other hand, 4,4'-byridine is a rigid rod-like spacer, well known in the construction of metal-organic polymers, and it has adopted numerous interesting supramolecular architectures (Batten & Robson, 1998). However, flexible ligands such as 1,4-bis(imidazole-1-ylmethyl)-benzene (1,4-bix) have not been so well explored to date (Yang et al., 2008). In this work, the combination of 1,4-bix with H₂chdc and Cd^II cations resulted in the title compound [Cd(1,4-bix)(Hchdc)₂], (I), a new one-dimensional chain coordination polymer.

The selected bond lengthes and angles are listed in Table 1. In compound (I), the Cd^II atom is is six-coordinated by four carboxylate O atoms from two different Hchdc ligands, and two N atoms from two different 1,4-bix molecules in a distorted octahedral environment (Fig. 1). The O1, O2, O2ⁱ and N1ⁱ atoms comprise the basal plane, whereas the N1 and O1ⁱ occupy the axial positions of the octahedron. As shown in Fig. 2, each 1,4-bix acts as a bridging ligand that binds two Cd^II atoms, thus forming a unique chain. The chain is decorated with Hchdc molecules alternately at two sides. Furthermore, the O—H···O hydrogen bonds link the chains together, stablizing the structure of (I).

Related literature top

For related structures, see: Qi et al. (2003). For background to coordination polymers, see: Chen & Liu (2002); Fang et al. (2006); Kim & Jung (2002); Lehn (1990); Batten & Robson (1998); Yang et al. (2008).

Experimental top

A mixture of CdCl₂^.2H₂O (0.5 mmol), H₂chdc acid (0.5 mmol), 1,4-bix (0.5 mmol), and H₂O (500 mmol) was adjusted to pH = 5.8 by addition of aqueous NaOH solution, and heated at 453 K for 5 days. After the mixture was slowly cooled to room temperature, colorless blocks of (I) were recovered in a 28% yield.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The structure of (I), showing displacement ellipsoids drawn at the 20% probability level. Symmetry code: (i) 3/2 - x, 1/2 - y, z; (ii) 5/2 - x, -1/2 - y, z.
	Fig. 2. View of the chain structure of (I).

catena-Poly[[bis(4-carboxycyclohexanecarboxylato- κ²O¹,O^1')cadmium(II)]-µ-1,4-bis(imidazol-1- ylmethyl)benzene-κ²N³:N^3'] top

Crystal data top

[Cd(C₈H₁₁O₄)₂(C₁₄H₁₄N₄)]	F(000) = 1424
M_r = 693.03	D_x = 1.475 Mg m⁻³
Orthorhombic, Pccn	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2ac	Cell parameters from 3190 reflections
a = 12.6317 (5) Å	θ = 3.0–26.5°
b = 19.9697 (12) Å	µ = 0.75 mm⁻¹
c = 12.3703 (7) Å	T = 292 K
V = 3120.4 (3) Å³	Block, colorless
Z = 4	0.26 × 0.22 × 0.17 mm

Data collection top

Oxford Diffraction Gemini R Ultra diffractometer	3190 independent reflections
Radiation source: fine-focus sealed tube	1658 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.116
Detector resolution: 10.0 pixels mm^-1	θ_max = 26.5°, θ_min = 4.7°
ω scans	h = −15→15
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −24→24
T_min = 0.816, T_max = 0.882	l = −15→15
26676 measured reflections

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.120	H-atom parameters constrained
S = 0.95	w = 1/[σ²(F_o²) + (0.0575P)²] where P = (F_o² + 2F_c²)/3
3190 reflections	(Δ/σ)_max < 0.001
195 parameters	Δρ_max = 0.62 e Å⁻³
0 restraints	Δρ_min = −0.30 e Å⁻³

Crystal data top

[Cd(C₈H₁₁O₄)₂(C₁₄H₁₄N₄)]	V = 3120.4 (3) Å³
M_r = 693.03	Z = 4
Orthorhombic, Pccn	Mo Kα radiation
a = 12.6317 (5) Å	µ = 0.75 mm⁻¹
b = 19.9697 (12) Å	T = 292 K
c = 12.3703 (7) Å	0.26 × 0.22 × 0.17 mm

Data collection top

Oxford Diffraction Gemini R Ultra diffractometer	3190 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	1658 reflections with I > 2σ(I)
T_min = 0.816, T_max = 0.882	R_int = 0.116
26676 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 0.95	Δρ_max = 0.62 e Å⁻³
3190 reflections	Δρ_min = −0.30 e Å⁻³
195 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	0.7200 (5)	0.1255 (3)	0.1946 (5)	0.0556 (16)
C2	0.7134 (5)	0.0551 (3)	0.1562 (5)	0.0703 (18)
H2	0.6472	0.0495	0.1158	0.084*
C3	0.8075 (6)	0.0347 (3)	0.0813 (6)	0.089 (2)
H3A	0.8072	0.0627	0.0172	0.107*
H3B	0.8738	0.0420	0.1190	0.107*
C4	0.7998 (7)	−0.0363 (4)	0.0488 (6)	0.106 (3)
H4A	0.8606	−0.0478	0.0045	0.127*
H4B	0.7367	−0.0427	0.0054	0.127*
C5	0.7956 (5)	−0.0833 (3)	0.1467 (6)	0.082 (2)
H5	0.7788	−0.1281	0.1192	0.099*
C6	0.7065 (7)	−0.0639 (4)	0.2243 (7)	0.098 (2)
H6A	0.6387	−0.0729	0.1905	0.118*
H6B	0.7113	−0.0910	0.2891	0.118*
C7	0.7123 (6)	0.0065 (3)	0.2537 (6)	0.089 (2)
H7A	0.7758	0.0137	0.2961	0.107*
H7B	0.6521	0.0172	0.2992	0.107*
C8	0.9032 (6)	−0.0881 (3)	0.2022 (7)	0.078 (2)
C9	0.9060 (3)	0.2554 (3)	0.4765 (4)	0.0524 (13)
H9	0.8851	0.2997	0.4856	0.063*
C10	0.9221 (4)	0.1567 (3)	0.4138 (5)	0.0657 (16)
H10	0.9152	0.1192	0.3699	0.079*
C11	0.9818 (5)	0.1601 (3)	0.5038 (5)	0.0665 (18)
H11	1.0218	0.1258	0.5339	0.080*
C12	1.0206 (3)	0.2510 (3)	0.6389 (4)	0.0612 (14)
H12A	0.9962	0.2257	0.7010	0.073*
H12B	0.9972	0.2969	0.6481	0.073*
C13	1.1951 (4)	0.2506 (5)	0.5441 (5)	0.125 (4)
H13	1.1592	0.2521	0.4785	0.150*
C14	1.1390 (3)	0.2497 (3)	0.6368 (4)	0.0479 (11)
C15	1.1954 (4)	0.2499 (4)	0.7277 (5)	0.0693 (15)
H15	1.1599	0.2498	0.7936	0.083*
N1	0.8735 (3)	0.2166 (2)	0.3967 (4)	0.0527 (11)
N2	0.9721 (3)	0.2237 (2)	0.5420 (4)	0.0515 (12)
O1	0.7903 (3)	0.1640 (2)	0.1601 (3)	0.0683 (11)
O2	0.6563 (3)	0.1466 (2)	0.2657 (4)	0.0700 (12)
O3	0.9194 (5)	−0.0730 (3)	0.2950 (5)	0.120 (2)
O4	0.9764 (4)	−0.1119 (2)	0.1406 (4)	0.0951 (15)
H4	1.0323	−0.1134	0.1741	0.143*
Cd1	0.7500	0.2500	0.27740 (4)	0.04487 (19)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.062 (4)	0.045 (3)	0.059 (4)	0.007 (3)	−0.007 (3)	0.005 (3)
C2	0.096 (5)	0.045 (3)	0.069 (4)	0.000 (3)	0.000 (4)	0.002 (3)
C3	0.149 (6)	0.058 (4)	0.061 (4)	−0.006 (4)	0.036 (5)	0.000 (4)
C4	0.118 (6)	0.103 (6)	0.096 (6)	0.048 (5)	−0.013 (5)	−0.008 (5)
C5	0.085 (4)	0.068 (4)	0.093 (6)	0.022 (4)	−0.020 (4)	0.014 (4)
C6	0.095 (5)	0.078 (5)	0.123 (7)	0.020 (4)	0.014 (5)	0.016 (5)
C7	0.111 (6)	0.065 (4)	0.092 (6)	−0.013 (4)	0.027 (4)	0.005 (4)
C8	0.089 (5)	0.058 (4)	0.087 (6)	0.029 (4)	−0.001 (4)	0.002 (4)
C9	0.036 (2)	0.060 (3)	0.062 (3)	0.015 (3)	−0.002 (3)	0.001 (4)
C10	0.067 (4)	0.055 (4)	0.075 (5)	0.009 (3)	−0.018 (3)	0.002 (3)
C11	0.060 (4)	0.062 (4)	0.077 (5)	0.014 (3)	−0.018 (3)	0.006 (3)
C12	0.037 (2)	0.094 (4)	0.052 (3)	0.009 (4)	−0.006 (2)	0.000 (4)
C13	0.042 (3)	0.291 (12)	0.042 (4)	−0.020 (7)	−0.008 (3)	−0.003 (6)
C14	0.040 (2)	0.062 (3)	0.042 (3)	−0.002 (3)	0.001 (2)	−0.009 (4)
C15	0.048 (3)	0.119 (5)	0.041 (3)	−0.006 (5)	0.004 (2)	−0.004 (5)
N1	0.039 (2)	0.056 (3)	0.064 (3)	0.000 (2)	−0.007 (2)	0.006 (3)
N2	0.030 (2)	0.069 (3)	0.056 (3)	−0.0009 (19)	−0.002 (2)	0.006 (2)
O1	0.083 (3)	0.058 (2)	0.064 (3)	0.001 (2)	0.021 (2)	−0.004 (2)
O2	0.051 (2)	0.059 (2)	0.100 (3)	−0.0010 (18)	0.015 (2)	−0.025 (2)
O3	0.143 (5)	0.130 (5)	0.088 (4)	0.059 (4)	−0.019 (4)	−0.005 (4)
O4	0.077 (3)	0.099 (4)	0.110 (4)	0.027 (3)	−0.007 (3)	−0.027 (3)
Cd1	0.0318 (2)	0.0523 (3)	0.0505 (3)	0.0036 (3)	0.000	0.000

Geometric parameters (Å, º) top

C1—O1	1.250 (6)	C9—N2	1.325 (7)
C1—O2	1.265 (6)	C9—H9	0.9300
C1—C2	1.487 (8)	C10—C11	1.347 (8)
C1—Cd1	2.716 (6)	C10—N1	1.361 (6)
C2—C7	1.548 (8)	C10—H10	0.9300
C2—C3	1.561 (8)	C11—N2	1.360 (7)
C2—H2	0.9800	C11—H11	0.9300
C3—C4	1.478 (9)	C12—N2	1.453 (7)
C3—H3A	0.9700	C12—C14	1.496 (6)
C3—H3B	0.9700	C12—H12A	0.9700
C4—C5	1.533 (10)	C12—H12B	0.9700
C4—H4A	0.9700	C13—C14	1.347 (7)
C4—H4B	0.9700	C13—C13ⁱ	1.388 (11)
C5—C8	1.526 (9)	C13—H13	0.9300
C5—C6	1.529 (9)	C14—C15	1.331 (7)
C5—H5	0.9800	C15—C15ⁱ	1.379 (10)
C6—C7	1.453 (9)	C15—H15	0.9300
C6—H6A	0.9700	O4—H4	0.8200
C6—H6B	0.9700	Cd1—N1	2.249 (4)
C7—H7A	0.9700	Cd1—O1	2.306 (4)
C7—H7B	0.9700	Cd1—O2	2.384 (4)
C8—O3	1.205 (8)	Cd1—N1ⁱⁱ	2.249 (4)
C8—O4	1.288 (8)	Cd1—O1ⁱⁱ	2.306 (4)
C9—N1	1.320 (7)	Cd1—O2ⁱⁱ	2.384 (4)

O1—C1—O2	119.0 (5)	C11—C10—N1	109.7 (5)
O1—C1—C2	120.8 (5)	C11—C10—H10	125.2
O2—C1—C2	120.2 (6)	N1—C10—H10	125.2
C1—C2—C7	110.2 (5)	C10—C11—N2	106.5 (5)
C1—C2—C3	113.2 (5)	C10—C11—H11	126.8
C7—C2—C3	107.8 (5)	N2—C11—H11	126.8
C1—C2—H2	108.5	N2—C12—C14	113.6 (4)
C7—C2—H2	108.5	N2—C12—H12A	108.8
C3—C2—H2	108.5	C14—C12—H12A	108.8
C4—C3—C2	111.2 (6)	N2—C12—H12B	108.8
C4—C3—H3A	109.4	C14—C12—H12B	108.8
C2—C3—H3A	109.4	H12A—C12—H12B	107.7
C4—C3—H3B	109.4	C14—C13—C13ⁱ	121.7 (3)
C2—C3—H3B	109.4	C14—C13—H13	119.2
H3A—C3—H3B	108.0	C13ⁱ—C13—H13	119.2
C3—C4—C5	112.0 (6)	C15—C14—C13	115.9 (4)
C3—C4—H4A	109.2	C15—C14—C12	121.3 (4)
C5—C4—H4A	109.2	C13—C14—C12	122.7 (5)
C3—C4—H4B	109.2	C14—C15—C15ⁱ	122.4 (3)
C5—C4—H4B	109.2	C14—C15—H15	118.8
H4A—C4—H4B	107.9	C15ⁱ—C15—H15	118.8
C8—C5—C6	112.9 (6)	C9—N1—C10	105.1 (5)
C8—C5—C4	111.2 (6)	C9—N1—Cd1	122.2 (4)
C6—C5—C4	111.5 (6)	C10—N1—Cd1	132.5 (4)
C8—C5—H5	106.9	C9—N2—C11	106.9 (5)
C6—C5—H5	106.9	C9—N2—C12	126.2 (5)
C4—C5—H5	106.9	C11—N2—C12	126.8 (5)
C7—C6—C5	111.5 (6)	C1—O1—Cd1	94.9 (3)
C7—C6—H6A	109.3	C1—O2—Cd1	90.9 (3)
C5—C6—H6A	109.3	C8—O4—H4	109.5
C7—C6—H6B	109.3	N1—Cd1—N1ⁱⁱ	97.9 (2)
C5—C6—H6B	109.3	N1—Cd1—O1	92.24 (16)
H6A—C6—H6B	108.0	N1ⁱⁱ—Cd1—O1	141.92 (15)
C6—C7—C2	114.3 (6)	N1—Cd1—O1ⁱⁱ	141.92 (15)
C6—C7—H7A	108.7	N1ⁱⁱ—Cd1—O1ⁱⁱ	92.24 (16)
C2—C7—H7A	108.7	O1—Cd1—O1ⁱⁱ	102.0 (2)
C6—C7—H7B	108.7	N1—Cd1—O2	97.33 (15)
C2—C7—H7B	108.7	N1ⁱⁱ—Cd1—O2	87.24 (15)
H7A—C7—H7B	107.6	O1—Cd1—O2	55.00 (14)
O3—C8—O4	122.2 (7)	O1ⁱⁱ—Cd1—O2	119.83 (15)
O3—C8—C5	124.4 (7)	N1—Cd1—O2ⁱⁱ	87.24 (15)
O4—C8—C5	113.3 (7)	N1ⁱⁱ—Cd1—O2ⁱⁱ	97.33 (15)
N1—C9—N2	111.8 (6)	O1—Cd1—O2ⁱⁱ	119.83 (15)
N1—C9—H9	124.1	O1ⁱⁱ—Cd1—O2ⁱⁱ	55.00 (14)
N2—C9—H9	124.1	O2—Cd1—O2ⁱⁱ	173.1 (2)

Symmetry codes: (i) −x+5/2, −y+1/2, z; (ii) −x+3/2, −y+1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O2ⁱⁱⁱ	0.82	1.86	2.644 (6)	161

Symmetry code: (iii) x+1/2, −y, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Cd(C₈H₁₁O₄)₂(C₁₄H₁₄N₄)]
M_r	693.03
Crystal system, space group	Orthorhombic, Pccn
Temperature (K)	292
a, b, c (Å)	12.6317 (5), 19.9697 (12), 12.3703 (7)
V (Å³)	3120.4 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.75
Crystal size (mm)	0.26 × 0.22 × 0.17

Data collection
Diffractometer	Oxford Diffraction Gemini R Ultra diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.816, 0.882
No. of measured, independent and observed [I > 2σ(I)] reflections	26676, 3190, 1658
R_int	0.116
(sin θ/λ)_max (Å⁻¹)	0.627

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.120, 0.95
No. of reflections	3190
No. of parameters	195
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.62, −0.30

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL-Plus (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Cd1—N1	2.249 (4)	Cd1—O2	2.384 (4)
Cd1—O1	2.306 (4)

O1—Cd1—O2	55.00 (14)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O2ⁱ	0.82	1.86	2.644 (6)	161

Symmetry code: (i) x+1/2, −y, −z+1/2.

Acknowledgements

The authors thank Henan University of Urban Construction for support of this work.

References

Batten, S. R. & Robson, R. (1998). Angew. Chem. Int. Ed. 37, 1460–1494. Web of Science CrossRef Google Scholar
Chen, X. M. & Liu, G. F. (2002). Chem. Eur. J. 8, 4811–4817. CrossRef PubMed CAS Google Scholar
Fang, Q.-R., Zhu, G.-S., Xue, M., Zhang, Q.-L., Sun, J.-Y., Guo, X.-D., Qiu, S.-L., Xu, S.-T., Wang, P., Wang, D.-J., Wei, Y. (2006). Chem. Eur. J. 12, 3754-3758. Web of Science CrossRef PubMed CAS Google Scholar
Kim, Y. J. & Jung, D.-Y. (2002). Chem. Commun. pp. 908–909. Web of Science CSD CrossRef Google Scholar
Lehn, J. M. (1990). Angew. Chem., Int. Ed. Engl. 29, 1304–1305. Google Scholar
Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England. Google Scholar
Qi, Y., Wang, Y., Hu, C., Cao, M., Mao, L. & Wang, E. (2003). Inorg. Chem. 42, 8519–8523. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Yang, J., Ma, J.-F., Batten, S. R. & Su, Z.-M. (2008). Chem. Commun. pp. 2233–2235. Web of Science CSD CrossRef Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.