Poly[(μ2-quinoline-3-carboxyl­ato-κ2 N:O)(μ2-quinoline-3-carboxyl­ato-κ3 N:O,O′)cadmium]

Xing Wang; Yong-Sheng Yan; He-Yi Sun; Shen-Tang Wang; Chun-Bo Liu

doi:10.1107/S1600536812001031

. 2012 Jan 18;68(Pt 2):m163. doi: 10.1107/S1600536812001031

Poly[(μ₂-quinoline-3-carboxylato-κ² N:O)(μ₂-quinoline-3-carboxylato-κ³ N:O,O′)cadmium]

Xing Wang ^a, Yong-Sheng Yan ^a, He-Yi Sun ^a, Shen-Tang Wang ^a, Chun-Bo Liu ^a,^*

PMCID: PMC3274893 PMID: 22346840

Abstract

In the title compound, [Cd(C₁₀H₆NO₂)₂]_n, the Cd^II atom is coordinated by three O atoms and two N atoms from four quinoline-3-carboxylate (L ⁻) ligands, leading to a distorted trigonal–bipyramidal geometry. The L ⁻ ligands link the Cd^II atoms into a plane parallel to (100), with one ligand being tridentate, coordinating via the N atom and chelating a second Cd atom, and the other being bidentate, bridging two Cd atoms via the N and one O atom.. This two-dimensional network extends into a double-layer network by π–π interactions, with centroid–centroid distances of 3.680 (2) and 3.752 (2) Å. Another type of π–π interaction between pyridine rings [centroid–centroid distance = 3.527 (2) Å] leads to a three-dimensional supramolecular architecture.

Related literature

For background to the applications of cadmium coordination polymers and nicotinic acids, see: Niu et al. (2006 ▶); Song et al. (2006 ▶), Chen (2003) ▶; Chi et al. (2007 ▶); Lu et al. (2007 ▶). For a closely related structure, see: Hu et al. (2007 ▶).

Experimental

Crystal data

[Cd(C₁₀H₆NO₂)₂]
M _r = 456.72
Monoclinic,
a = 28.5458 (19) Å
b = 8.2274 (5) Å
c = 15.381 (1) Å
β = 112.708 (1)°
V = 3332.3 (4) Å³
Z = 8
Mo Kα radiation
μ = 1.34 mm⁻¹
T = 153 K
0.13 × 0.11 × 0.10 mm

Data collection

Rigaku Saturn 724+ CCD area-detector diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2007 ▶) T _min = 0.845, T _max = 0.910
7361 measured reflections
3014 independent reflections
2659 reflections with I > 2σ(I)
R _int = 0.015

Refinement

R[F ² > 2σ(F ²)] = 0.019
wR(F ²) = 0.051
S = 1.10
3014 reflections
244 parameters
H-atom parameters constrained
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Data collection: CrystalClear (Rigaku, 2007 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: CrystalClear (Rigaku, 2007 ▶) and DIAMOND (Brandenburg, 1998 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812001031/vn2029sup1.cif

e-68-0m163-sup1.cif^{(28KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812001031/vn2029Isup2.hkl

e-68-0m163-Isup2.hkl^{(145KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Cd1—N1ⁱ	2.3410 (16)
Cd1—N2	2.3188 (17)
Cd1—O1	2.1625 (15)
Cd1—O3ⁱⁱ	2.3858 (15)
Cd1—O4ⁱⁱ	2.2770 (15)

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The authors are thankful to Jiangsu University for support of this research.

supplementary crystallographic information

Comment

To date, much effort has been made on the construction of cadmium coordination polymers with a wide variety of topological structures which may possess promising perspectives toward molecular luminescent materials (Chi et al., 2007; Niu et al., 2006; Song et al., 2006; Lu et al., 2007). It is well known that nicotinic acid has been proved to be effective for constructing coordination polymers due to the versatile coordination fashion (Chen et al., 2003; Song et al., 2006). Compared with nicotinic acid, the structurally similar quinoline-3-carboxylic acid (HL) have been chosen to construct a new coordination polymer. Here, we report on the crystal structure of the title compound.

There is one cadmium (II) atom and two independent L^- ligands in the asymmetric unit. The Cd (II) atom is five-coordinated by two N atoms [Cd1—N1ⁱⁱ=2.341 (2) Å, Cd1—N2=2.319 (2) Å] and three O atoms [Cd1—O1=2.163 (2) Å, Cd—O3ⁱ=2.386 (2) Å, Cd—O4ⁱ=2.277 (2) Å] from four L^- ligands, showing a distorted trigonal bipyramidal coordination geometry (Fig. 1). The L^- ligand containing the N1 atom, acts as bis-monodentate mode toward cadmium centers with pyridine nitrogen atoms linking the cadmium atom and the carboxylate group linking the cadmium atom in a monodentate fashion, leading to the formation of a 1D chain structure along the the b axis. The 1D chains are linked into a 2D layer network by bis-chelating L^- ligand containing the N2 atom, There is in addition a 2D double-layer structure (black bond and green bond) which is connected by π–π interactions with the centroid to centroid distances of 3.680 (2) and 3.752 (2) Å, respectively (Fig. 2). The 2D double-layers are parallel to the (100) plane, and linked to each other by another type of π–π interaction between pyridine rings [centroid-to-centroid 3.527 (2) Å], resulting in a 3D supramolecular architecture.

There is a reported isostructural Zn analogue (Hu et al., 2007) which has a tetrahedral environment with L^- in a bis-monodentate mode, while the title compound shows a distorted trigonal bipyramidal coordination geometry with L^- in bis-monodentate and bis-chelating modes, respectively (Fig. 3). This comparison reveals the influence of different metal ion on the coordination mode of the ligand.

Experimental

Quinoline-3-carboxylic acid (HL) was purchased commercially and used without further purification. A mixture of CdCl₂ (18.400 mg, 0.1 mmol), and HL (17.300 mg, 0.1 mmol) was dissolved in a 10 mL of water with a pH = 6. The resulting mixture was heated in a 15 mL autoclave with Teflon-liner at 438 K for three days. Then the autoclave was slowly cooled to room temperature, and colourless block-shaped crystals were obtained with a yield of 50 %.