Tetra­kis(μ-2-phenyl­quinoline-4-carboxyl­ato-κ2 O:O′)bis­[(methanol-κO)copper(II)]

Junfang Guo; Guoping Yan

doi:10.1107/S1600536812039839

. 2012 Sep 26;68(Pt 10):m1296. doi: 10.1107/S1600536812039839

Tetrakis(μ-2-phenylquinoline-4-carboxylato-κ² O:O′)bis[(methanol-κO)copper(II)]

Junfang Guo ^a,^*, Guoping Yan ^a

PMCID: PMC3470168 PMID: 23125612

Abstract

The title complex, [Cu₂(C₁₆H₁₀NO₂)₄(CH₃OH)₂], consists of centrosymmetric wheel-shaped dinuclear neutral molecules in which each Cu^II atom is coordinated in a slightly distorted square-pyramidal geometry by four O atoms of carboxylate groups from different ligands at the basal plane and an O atom of a methanol molecule at the axial position. In the crystal, the dinuclear complex molecules are linked into one-dimensional supramolecular columns parallel to the b axis by O—H⋯N hydrogen bonds and π–π stacking interactions [centroid–centroid distance = 3.7259 (11) Å].

Related literature

For the background to isonicotinic acid derivatives as polyfunctional ligands, see: Evans & Lin (2002 ▶); Aakeröy et al. (1999 ▶); Xiong et al. (2000 ▶); Qin et al. (2002 ▶); Shen et al. (2007 ▶). For the structures of related compounds, see: Bu et al. (2005 ▶); Wang et al. (2010 ▶); Ma & Lin (2008 ▶).

Experimental

Crystal data

[Cu₂(C₁₆H₁₀NO₂)₄(CH₄O)₂]
M _r = 1184.16
Triclinic,
a = 8.9671 (6) Å
b = 10.5859 (7) Å
c = 14.7767 (10) Å
α = 89.800 (1)°
β = 87.348 (1)°
γ = 77.300 (1)°
V = 1366.86 (16) Å³
Z = 1
Mo Kα radiation
μ = 0.85 mm⁻¹
T = 293 K
0.31 × 0.24 × 0.17 mm

Data collection

Bruker APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ▶) T _min = 0.780, T _max = 0.870
7266 measured reflections
4984 independent reflections
4583 reflections with I > 2σ(I)
R _int = 0.014

Refinement

R[F ² > 2σ(F ²)] = 0.033
wR(F ²) = 0.088
S = 1.06
4984 reflections
370 parameters
H-atom parameters constrained
Δρ_max = 0.48 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Data collection: SMART (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); 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.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812039839/rz5004sup1.cif

e-68-m1296-sup1.cif^{(26.6KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812039839/rz5004Isup2.hkl

e-68-m1296-Isup2.hkl^{(244.1KB, 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
O5—H1⋯N1ⁱ	0.83	1.95	2.784 (2)	176

Open in a new tab

Symmetry code: (i) Inline graphic .

Acknowledgments

The work described in this paper was supported by grants from the National Natural Science Foundation of China (NSFC 21001085), the Hubei Province Natural Science Foundation (2010CDB11104), and the Doctoral Program Foundation of Wuhan Institute of Technology (11105032).

supplementary crystallographic information

Comment

Isonicotinic acid and its derivatives, such as 9-acridinecarboxylic acid and 4-quinolinecarboxylic acid, bearing both neutral and anionic donor groups, have been widely used as polyfunctional ligands (Evans & Lin, 2002; Aakeröy et al., 1999; Xiong et al., 2000; Bu et al., 2005). 2-Phenylquinoline-4-carboxylic acid (HL), an analogue of isonicotinic acid, exhibits flexible ligation modes in the construction of diverse coordination motifs with unusual properties (Qin et al., 2002; Shen et al., 2007; Wang et al., 2010). Herein, we report a new copper(II) complex derived from 2-phenylquinoline-4-carboxylic acid.

The title complex shows a dinuclear paddle-wheel unit [Cu₂(L)₄(CH₃OH)₂] (Fig. 1), which is composed of two copper(II) ions, four L ligands and two methanol molecules. Each metal is pentacoordinated by four O atoms of the carboxylate groups from different ligands [Cu—O mean length = 1.961 (3) Å] at the equatorial plane and one O atom of a CH₃OH molecule at the axial position. One of the most common parameters used to define the coordination geometry of a pentacoordinated metal center, the τ index, is 0.0003, indicating an almost-ideal square-pyramidal coordination. The metal ion deviates from the mean equatorial plane of the square pyramid toward the apical O5 atom by 0.1942 (3) Å. The Cu···Cu distance is 2.6303 (5) Å, which is within the normal range observed for dinuclear paddle-wheel units in the structures of copper(II) carboxylate complexes (Bu et al., 2005; Wang et al., 2010; Ma & Lin, 2008). In the crystal (Fig. 2), the dinuclear complex molecules are linked into one-dimensional columns parallel to the b axis through intermolecular O—H···N hydrogen bonds (Table 1) and π–π stacking interactions involving adjacent quinoline rings, with centroid–centroid distances of 3.7259 (11) Å and perpendicular interplanar separations of 3.4838 (8) Å.

Experimental

2-Phenylquinoline-4-carboxylic acid (49.8 mg, 0.2 mmol) in CH₃OH/CHCl₃ solution (1:1 v/v, 25 ml) was added to a CH₃OH solution (25 ml) of Cu(NO₃)₂.2.5H₂O (46.5 mg, 0.2 mmol). The resulting solution was filtered and left to stand at room temperature. Green block-shaped single crystals suitable for X-ray analysis were obtained after several days (yield: 45%).