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

Muhammad Danish; Iram Saleem; M Nawaz Tahir; Nazir Ahmad; Abdur Rauf Raza

doi:10.1107/S1600536810013322

. 2010 Apr 17;66(Pt 5):m528. doi: 10.1107/S1600536810013322

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

Muhammad Danish ^a, Iram Saleem ^a, M Nawaz Tahir ^b,^*, Nazir Ahmad ^a, Abdur Rauf Raza ^a

PMCID: PMC2979172 PMID: 21579022

Abstract

In the title compound, [Cu₂(C₈H₇O₂)₄(CH₃OH)₂], the Cu—O bond distances are in the range 1.943 (2)–2.149 (2) Å within a sligthly distorted square-pyramidal coordination. The Cu⋯Cu separation is 2.5912 (4) Å. In the crystal, the molecules are linked into polymeric chains propagating in [001] by intermolecular O—H⋯O hydrogen bonds and C—H⋯π interactions.

Related literature

For our work on the synthesis of various metal complexes of 2-methylbenzoic acid, see: Danish et al. (2010 ▶). For related structures, see: Kabbani et al. (2004 ▶); Rao et al. (1983 ▶); Sunil et al. (2008 ▶); Xin & Liu (2008 ▶).=

Experimental

Crystal data

[Cu₂(C₈H₇O₂)₄(CH₄O)₂]
M _r = 731.71
Triclinic,
a = 10.7474 (9) Å
b = 12.1403 (11) Å
c = 14.1709 (11) Å
α = 113.805 (2)°
β = 91.096 (3)°
γ = 93.238 (3)°
V = 1687.2 (2) Å³
Z = 2
Mo Kα radiation
μ = 1.32 mm⁻¹
T = 296 K
0.30 × 0.14 × 0.08 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.804, T _max = 0.898
27787 measured reflections
8232 independent reflections
5004 reflections with I > 2σ(I)
R _int = 0.047

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.098
S = 1.02
8232 reflections
427 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.31 e Å⁻³

Data collection: APEX2 (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: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and PLATON.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810013322/bq2206sup1.cif

e-66-0m528-sup1.cif^{(35.5KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810013322/bq2206Isup2.hkl

e-66-0m528-Isup2.hkl^{(394.6KB, hkl)}

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

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

Cg1 and Cg2 are the centroids of C2–C7 and C28–C33 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5A⋯O7ⁱ	0.70 (3)	2.11 (3)	2.793 (3)	167 (4)
O6—H6A⋯O2ⁱⁱ	0.72 (3)	2.10 (3)	2.812 (2)	174 (4)
C18—H18A⋯Cg1ⁱⁱ	0.96	2.98	3.749 (4)	137.00
C23—H23⋯Cg1ⁱⁱⁱ	0.93	2.87	3.735 (4)	154.00
C13—H13⋯Cg2^iv	0.93	2.97	3.877 (4)	165.00

Open in a new tab

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

Acknowledgments

The authors acknowledge the provision of funds for the purchase of diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha. The authors also acknowledge the technical support provided by Bana International, Karachi, Pakistan.

supplementary crystallographic information

Comment

In continuation to synthesize various metal complexes of 2-methylbenzoic acid (Danish et al., 2010), the title compound (I) (Fig. 1) is being reported here.

The crystal structure of (II) Tetrakis(µ-2-methylbenzoato-O,O') -bis(2-methylbenzoic acid-O)-di-copper(ii) (Sunil et al., 2008) has been reported. The title compound (I) differs from (II) due to the bonding of methanol at apical positions instead of o-toluic acid. The crystal structures of (III) Tetrakis(µ-2-anilinobenzoato)-bis(methanol-copper(ii)) (Xin & Liu, 2008), (IV) Tetrakis(µ-4-chloro-3-nitrobenzoato)-bis(methanol)-di-copper(ii) (Kabbani et al., 2004) and (V) Tetrakis(µ-acetato)-bis(methanol)-di-copper(ii) (Rao et al., 1983) have also been reported which have similar environments around Cu-atoms as in (I).

Although the space group is centrosymmetric but the molecules of (I) are not centrosymmetric. The C-atoms of 2-methylbenzoato A (C1—C8), B (C9—C16), C (C19—C26) and D (C27—C34) are planar with maximum r. m. s. deviations of 0.0148, 0.0278, 0.0111 & 0.0127 Å respectively, from the mean square planes. The carboxylato groups E (O1/C1/O2), F (O3/C9/O4), G (O7/C19/O8) and H (O9/C27/O10) are of course planar. The dihedral angle between A/E, B/F, C/G and D/H is 35.01 (23), 40.19 (20), 36.09 (25) and 27.16 (33)° respectively. The oppositely bonded 2-methylbenzoato groups with Cu-atoms make dihedral angles A/C 75.77 (7)° and B/D 86.29 (7)° which confirms that asymmetric units cannot be centrosymmetric. The coordination of Cu–O bond distances range 1.943 (2)–2.149 (2) Å [Table 1] and the separation between Cu to Cu is 2.5912 (4) Å. The molecules are stabilized in the form of polymeric chains due to intermolecular H-bondings and C–H···π interactions (Table 2, Fig. 2).

Experimental

The sodium salt of 2-methylbenzoic acid (1 g, 6.32 mmol) was dissolved in 20 ml distilled water. Cu₂So₄.5H₂O (0.789 g, 3.16 mmol) was separately dissolved in 20 ml distilled water. The former solution was slowly added to the later under continuous stirring with the formation of greenish precipitates. The reaction mixture was refluxed for 3 h and cooled to room temperature. The residue of filtration was crystallized in methanol:water (1:1). Green plate like crystals were obtained after 48 h.