Diaqua­bis­(2-oxo-2H-chromene-3-carboxyl­ato)copper(II)

Yue Cui; Qian Gao; Huan-Huan Wang; Lin Wang; Ya-Bo Xie

doi:10.1107/S1600536811018708

. 2011 May 20;67(Pt 6):m782. doi: 10.1107/S1600536811018708

Diaquabis(2-oxo-2H-chromene-3-carboxylato)copper(II)

Yue Cui ^a, Qian Gao ^a, Huan-Huan Wang ^a, Lin Wang ^a, Ya-Bo Xie ^a,^*

PMCID: PMC3120618 PMID: 21754664

Abstract

In the title compound, [Cu(C₁₀H₅O₄)₂(H₂O)₂], the Cu^II atom lies on a crystallographic inversion center and exhibits an octahedral coordination defined by two O atoms from water molecules in the axial positions and by four O atoms from two deprotonated coumarin-3-carboxylic acid ligands in the equatorial positions. The angles around the Cu^II atom vary between 85.32 (6) and 94.68 (6)°. The Cu—O bond distances between the Cu^II atom and the O atoms vary between 1.9424 (14) and 2.3229 (15) Å. The layers interdigitate via face-to-face aromatic interactions [3.6490 (8) Å] between coumarin moieties such that the interlayer separation is 10.460 (2) Å, i.e. the length of the c axis. O—H⋯O hydrogen bonds between the H atoms of coordinated water molecules and the O atoms of carboxylate groups link the complex molecules into layers parallel to the ab plane.

Related literature

For background to topological networks, see: Lazarou et al. (2011 ▶). For applications of copper(II) complexes, see: Eddaoudi et al. (2001 ▶); Kirillov et al. (2010 ▶); Konidaris et al. (2009 ▶). For related structures, see: Wang et al. (2011 ▶).

Experimental

Crystal data

[Cu(C₁₀H₅O₄)₂(H₂O)₂]
M _r = 477.86
Triclinic,
a = 6.5884 (13) Å
b = 6.8296 (14) Å
c = 10.460 (2) Å
α = 85.98 (3)°
β = 89.79 (3)°
γ = 65.38 (3)°
V = 426.65 (15) Å³
Z = 1
Mo Kα radiation
μ = 1.35 mm⁻¹
T = 293 K
0.20 × 0.15 × 0.15 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008a ▶) T _min = 0.785, T _max = 0.817
2696 measured reflections
1954 independent reflections
1926 reflections with I > 2σ(I)
R _int = 0.014

Refinement

R[F ² > 2σ(F ²)] = 0.026
wR(F ²) = 0.080
S = 1.10
1954 reflections
146 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.59 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b ▶); molecular graphics: SHELXTL (Sheldrick, 2008b ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811018708/zk2008sup1.cif

e-67-0m782-sup1.cif^{(16.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811018708/zk2008Isup2.hkl

e-67-0m782-Isup2.hkl^{(96.1KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯O4ⁱ	0.82	1.89	2.706 (2)	177
O1W—H1WB⋯O4ⁱⁱ	0.88 (3)	1.90 (3)	2.753 (2)	163 (3)

Open in a new tab

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

Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 21075114), the Special Environmental Protection Fund for Public Welfare project (201009015) and the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the jurisdiction of the Beijing Municipality (PHR 201107104).

supplementary crystallographic information

Comment

In the past decades, numerous papers dealing with copper(II) complexes have been published due to their fascinating structural diversity (Lazarou et al., 2011) and potential applications in the areas of catalysis (Kirillov et al., 2010), gas addsorption (Eddaoudi et al., 2001), magnetism (Konidaris et al., 2009) and so on. Herein, we report the synthesis and crystal structure of a new mononuclear copper complex coordinated by coumarin-3-carboxylic acid.

In the title compound, [Cu(C₁₀H₅O₄)₂(H₂O)₂], copper(II) atom lies on a crystallographic inversion center and exhibits octahedral geometry with the coordination of two O atoms from water molecules in the axial positions and four O atoms from two deprotonated coumarin-3-carboxylic acid ligands in the equatorial positions. Angles around the Cu^II atom vary between 85.32 (6)° and 94.68 (6)°. The Cu—O bond distances between the Cu^II atom and the O atoms vary between 1.9424 (14) and 2.3229 (15) Å, all of which are comparable to those reported for other copper-oxygen donor complexes (e.g., Wang et al., 2011). The (C2C1C3C4C5C6) ring and the (C4C3C7C9C8O2) ring are almost coplanar, and the dihedral angles is 1.568 (57)°. The layers interdigitate via face to face aromatic interactions (distance 3.6490 (8) Å) between coumarin moieties such that the interlayer separation is 10.46 Å, length of c axis. O—H···O hydrogen bonds between the hydrogen atoms of coordinated water molecules and the O atoms of carboxylate groups joins the complexes into two-dimensional layers parallel the ab plane (Table 1 and Fig. 2).

Experimental

The title complex was synthesized by carefully layering a solution of Cu(NO₃)₂.3H₂O (24.2 mg, 0.1 mmol) in ethanol (10 ml) on top of a solution of coumarin-3-carboxylic acid (19.0 mg, 0.1 mmol) and LiOH (8.4 mg, 0.2 mmol) in H₂O (10 ml) in a test-tube. After about one month at room temperature, green block-shaped single crystals suitable for X-ray investigation appeared at the boundary between the ethanol solution and the water layer with a yield of 25% (12.1 mg). FT—IR (KBr, cm^-1): 788, 1028, 1183, 1285, 1388, 1457, 1560, 1697, 3180.