catena-Poly[[bis­(5-chloro-2-nitro­benzoato)copper(II)]-bis­(μ-5-chloro-2-nitro­benzoato)]

Eng Khoon Lim; Siang Guan Teoh; Ibrahim Abdul Razak; Hoong-Kun Fun

doi:10.1107/S1600536809001895

. 2009 Jan 23;65(Pt 2):m211–m212. doi: 10.1107/S1600536809001895

catena-Poly[[bis(5-chloro-2-nitrobenzoato)copper(II)]-bis(μ-5-chloro-2-nitrobenzoato)]

Eng Khoon Lim ^a, Siang Guan Teoh ^a, Ibrahim Abdul Razak ^b,^‡, Hoong-Kun Fun ^b,^*

PMCID: PMC2968352 PMID: 21581807

Abstract

In the title compound, [Cu₂(C₇H₃ClNO₄)₄]_n, the coordination geometry around each Cu^II ion is distorted square-pyramidal. The CuO₅ coordination is formed by five O atoms from the carboxylate groups of five 5-chloro-2-nitrobenzoate ligands. This coordination leads to the formation of centrosymmetric binuclear units which are edge-shared, forming a linear chain along the a axis, with the Cu^II ions alternately separated by 2.5891 (4) and 3.1763 (4) Å. The chains are interconnected into a three-dimensional network by C—H⋯O interactions.

Related literature

For general background, see: Balaraman et al. (2006 ▶); Tomoya et al. (2005 ▶). For bond-length data, see: Allen et al. (1987 ▶). For related structures, see: Kabbani et al. (2004 ▶); Stachová et al. (2004 ▶).

Experimental

Crystal data

[Cu₂(C₇H₃ClNO₄)₄]
M _r = 929.30
Triclinic,
a = 5.0353 (1) Å
b = 11.8001 (3) Å
c = 13.8595 (3) Å
α = 84.539 (2)°
β = 85.553 (1)°
γ = 85.610 (2)°
V = 815.30 (3) Å³
Z = 1
Mo Kα radiation
μ = 1.72 mm⁻¹
T = 100.0 (1) K
0.47 × 0.21 × 0.08 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.498, T _max = 0.875
11613 measured reflections
4656 independent reflections
3994 reflections with I > 2σ(I)
R _int = 0.034

Refinement

R[F ² > 2σ(F ²)] = 0.035
wR(F ²) = 0.116
S = 1.10
4656 reflections
244 parameters
H-atom parameters constrained
Δρ_max = 0.72 e Å⁻³
Δρ_min = −1.04 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809001895/ci2748sup1.cif

e-65-0m211-sup1.cif^{(20.8KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809001895/ci2748Isup2.hkl

e-65-0m211-Isup2.hkl^{(228.1KB, hkl)}

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

Table 1. Selected bond lengths (Å).

Cu1—O5	1.942 (2)
Cu1—O6ⁱ	1.946 (2)
Cu1—O2ⁱⁱ	1.950 (2)
Cu1—O1ⁱⁱⁱ	2.008 (2)
Cu1—O1	2.165 (2)

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

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯O4^iv	0.93	2.44	3.254 (3)	146
C11—H11A⋯O8^v	0.93	2.46	3.384 (3)	172
C14—H14A⋯O4ⁱ	0.93	2.54	3.417 (3)	156

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Symmetry codes: (i) Inline graphic ; (iv) ; (v) .

Acknowledgments

HKF thanks the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312.

supplementary crystallographic information

Comment

The ability to induce DNA cleavage in the presence of H₂O₂ and reductants by phenanthroline-based copper complexes such as [Cu(imda)(5,6-dmp)] (where 5,6-dmp is 5,6-dimethyl-1,10-phenanthroline) and [Cu(N,N'-dialkyl-1,10-phenanthroline -2,9-dimethanamine)] (Balaraman et al., 2006; Tomoya et al., 2005) have driven us to investigate the DNA cleavage ability of benzoic acid-based copper complexes. Several benzoic acid-based copper complexes have been prepared in our laboratory and their DNA cleavage abilities are further investigated. In this paper, we report the crystal structure of the title compound.

In the title compound, the coordination geometry around each Cu^II ion can be described as square-pyramidal, formed by five O atoms from the carboxylate groups of five 5-chloro-2-nitrobenzoate ligands. The basal plane positions are occupied by atoms O5, O6A, O2B and O1C with an average Cu—O bond length of 1.962 (2) Å. The apical position is occupied by atom O1 (Fig.1). The Cu1 atom is displaced away from the basal plane by 0.1689 (3) Å and the Cu—Cu(-x,-y,1 - z) separation is 2.5891 (4) Å. Similar CuO₅ coordination were observed in related structures reported by Kabbani et al. (2004) and Stachová et al. (2004). The CuO₅ square pyramids are edge-shared to form a linear polymeric chain along the a axis. In the chain, the Cu^II ions are alternately separated by 2.5891 (4) and 3.1763 (4) Å.

Bond lengths of the ligands have normal values (Allen et al., 1987). The dihedral angle between nitro groups and the benzene rings are: C1–C6/N1/O3/O4 = 12.0 (3)° and C9–C14/N2/O7/O8 = 65.1 (3)°.

The polymeric chains are interconnected through C—H···O intramolecular interactions, forming a three-dimensional network (Table 2 and Fig. 2).

Experimental

An ethanol solution (50 ml) of 5-chloro-2-nitrobenzoic acid (4.84 g, 0.024 mol) was added to a solution of copper(II) sulfate pentahydrate (3.00 g, 0.012 mol) in ethanol (50 ml) and the mixture was stirred and refluxed for 2 h. The resulting solution was filtered and left to cool down to room temperature. After a few days of slow evaporation, blue crystals suitable for X-ray analysis were collected.