Tetra-μ2-acetato-κ8 O:O′-bis­[(isoquinoline-κN)copper(II)]

Meng-Jiao Li; Jing-Jing Nie; Duan-Jun Xu

doi:10.1107/S1600536809025732

. 2009 Jul 8;65(Pt 8):m881. doi: 10.1107/S1600536809025732

Tetra-μ₂-acetato-κ⁸ O:O′-bis[(isoquinoline-κN)copper(II)]

Meng-Jiao Li ^a, Jing-Jing Nie ^a, Duan-Jun Xu ^a,^*

PMCID: PMC2977170 PMID: 21583345

Abstract

In the crystal structure of the title compound, [Cu₂(CH₃COO)₄(C₉H₇N)₂], the Cu^II cation is coordinated by four acetate anions and one isoquinoline molecule in a distorted square-pyramidal geometry; the Cu^II cation is 0.1681 (6) Å from the basal coordination plane formed by the four O atoms. Each acetate anion bridges two Cu^II cations to form the centrosymmetric dinuclear complex. Within the dinuclear molecule, the Cu⋯Cu separation is 2.6459 (4) Å. A parallel arrangement of isoquinoline ligands of adjacent complexes is observed in the crystal structure; the face-to-face distance of 3.610 (10) Å suggests there is no π–π stacking between isoquinoline ring systems.

Related literature

For general background on the nature of π–π stacking, see: Su & Xu (2004 ▶); Xu et al. (2007 ▶). For related isoquinoline complexes, see: Clegg & Straughan (1989 ▶); Ivanikova et al. (2006 ▶). For a related quinoline complex, see: Pan & Xu (2004 ▶). For the metal atomic deviation from the basal coordination plane in square-pyramidal coordination geometry, see: Xie & Xu (2005 ▶). For the Cu⋯Cu distance in a polymeric Cu^II complex, see: Li et al. (2007 ▶).

Experimental

Crystal data

[Cu₂(C₂H₃O₂)₄(C₉H₇N)₂]
M _r = 621.57
Monoclinic,
a = 12.2278 (3) Å
b = 8.1610 (2) Å
c = 13.5309 (4) Å
β = 103.827 (8)°
V = 1311.13 (7) Å³
Z = 2
Mo Kα radiation
μ = 1.67 mm⁻¹
T = 294 K
0.28 × 0.26 × 0.20 mm

Data collection

Rigaku R-AXIS RAPID IP diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ▶) T _min = 0.635, T _max = 0.720
12480 measured reflections
2997 independent reflections
2638 reflections with I > 2σ(I)
R _int = 0.024

Refinement

R[F ² > 2σ(F ²)] = 0.025
wR(F ²) = 0.074
S = 1.06
2997 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.40 e Å⁻³

Data collection: PROCESS-AUTO (Rigaku, 1998 ▶); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002 ▶); program(s) used to solve structure: SIR92 (Altomare et al., 1993 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809025732/bq2151sup1.cif

e-65-0m881-sup1.cif^{(17.3KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809025732/bq2151Isup2.hkl

e-65-0m881-Isup2.hkl^{(144.1KB, hkl)}

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

Table 1. Selected bond lengths (Å).

Cu—N1	2.1789 (15)
Cu—O1	1.9771 (13)
Cu—O2ⁱ	1.9728 (13)
Cu—O3	1.9777 (13)
Cu—O4ⁱ	1.9740 (13)

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Symmetry code: (i) Inline graphic .

Acknowledgments

This work was supported by the ZIJIN project of Zhejiang University, China.

supplementary crystallographic information

Comment

As part of our ongoing investigation on the nature of π-π stacking (Su & Xu, 2004; Xu et al., 2007), the title complex incorporating isoquinoline ligand has recently been prepared in the laboratory and its crystal structure is reported here.

The molecular structure is shown in Fig. 1. The Cu^II cation is coordinated by four O atoms from four acetate anions in the basal plane, an isoquinoline molecule coordinates to the Cu^II cation in the apical position to complete the distorted square-pyramidal coordination geometry. The Cu^II cation is 0.1681 (6) Å deviated from the basal coordination plane, which is consistent with the situation found in complexes with square-pyramidal coordination geometry (Xie & Xu, 2005). The Cu—N bond in the apical direction is longer than Cu—O bonds in the basal plane by ca 0.2 Å, showing the typical Jahn-Teller distortion. Each acetate anion bridges two Cu^II cations to form the centro-symmetric dinuclear complex. Within the dinuclear molecule the Cu···Cu separation is 2.6459 (4) Å, similar to 2.642 Å found in a polymeric Cu^II complex bridged by thiourea (Li et al. 2007).

The parallel arrangement of isoquinoline ligands of adjacent complexes is observed in the crystal structure (Fig. 2). The face-to-face distance of 3.610 (10) Å is close to 3.573 (5) Å found in a quinoline complex (Pan & Xu, 2004) and suggests no π-π stacking between isoquinoline ring systems.

Experimental

A water-ethanol solution (10 ml, 1:2) of isoquinoline (0.12 ml, 1 mmol) and copper acetate monohydrate (0.10 g, 0.5 mmol) was refluxed for 2.5 h. After cooling to room temperature the solution was filtered. The single crystals of the title compound were obtained from the filtrate after 3 d.