{2,2′-[4,5-Dibromo-o-phenyl­enebis(nitrilo­dimethyl­idyne)]diphenolato-κ4 O,N,N′,O′}(methanol-κO)copper(II)

Jianxin Xing

doi:10.1107/S1600536809011179

. 2009 Mar 31;65(Pt 4):m469. doi: 10.1107/S1600536809011179

{2,2′-[4,5-Dibromo-o-phenylenebis(nitrilodimethylidyne)]diphenolato-κ⁴ O,N,N′,O′}(methanol-κO)copper(II)

Jianxin Xing ^a,^*

PMCID: PMC2968844 PMID: 21582399

Abstract

In the title compound, [Cu(C₂₀H₁₂Br₂N₂O₂)(CH₃OH)], the Cu^II ion, and the C, O and hydroxy H atoms of the coordinated methanol molecule are located on a twofold rotation axis, while the methyl H atoms are disordered over two sites about the rotation axis. The Cu^II ion is coordinated by two N atoms [Cu—N = 1.960 (4) Å] and two O atoms [Cu—O = 1.908 (4) Å] from the tetradentate Schiff base ligand and by one O atom [Cu—O = 2.324 (6) Å] of the methanol molecule in a square-pyramidal geometry. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link complex molecules into extended chains along [001].

Related literature

For a related crystal structure, see Saha et al. (2007 ▶). For general background related to Schiff base compounds, see: Ghosh et al. (2006 ▶); Nayka et al. (2006 ▶); Singh et al. (2007 ▶); Yu et al. (2007 ▶).

Experimental

Crystal data

[Cu(C₂₀H₁₂Br₂N₂O₂)(CH₄O)]
M _r = 567.72
Orthorhombic,
a = 19.164 (4) Å
b = 19.416 (4) Å
c = 5.3287 (10) Å
V = 1982.7 (6) Å³
Z = 4
Mo Kα radiation
μ = 5.16 mm⁻¹
T = 273 K
0.21 × 0.15 × 0.13 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.411, T _max = 0.554 (expected range = 0.379–0.511)
9881 measured reflections
2004 independent reflections
1517 reflections with I > 2σ(I)
R _int = 0.046

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.111
S = 1.06
2004 reflections
137 parameters
242 restraints
H-atom parameters constrained
Δρ_max = 1.23 e Å⁻³
Δρ_min = −1.82 e Å⁻³

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: SAINT-Plus (Bruker, 2001 ▶); data reduction: SAINT-Plus; 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 datablocks global, I. DOI: 10.1107/S1600536809011179/lh2794sup1.cif

e-65-0m469-sup1.cif^{(15.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809011179/lh2794Isup2.hkl

e-65-0m469-Isup2.hkl^{(98.7KB, 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
O2—H2A⋯O1ⁱ	0.82	2.30	3.009 (6)	145

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Symmetry code: (i) Inline graphic .

supplementary crystallographic information

Comment

Schiff-bases have played an important role in the development of coordination chemistry as they readily form stable complexes with most of the transition metals, in which some may exhibit interesting properties (Yu et al., 2007; Ghosh et al., 2006; Singh et al., 2007; Nayka et al., 2006). Here, we report a new Cu(II) complex based on the tetradentate Schiff-base ligand 4,5-dibromo-1,2-diaminobenzene-N,N'-bis (salicylideneimine).

The molecular structure of the title compound is shown in Fig. 1. The Cu^II ion is pentacoordinated with the four basal sites occupied by two N atoms and two O atoms of the Schiff-base ligand, while the apical site is occupied by the O atom of the coordinated methanol molecule. The Cu^II ion is displaced towards the Cu—O_methanol bond from the plane formed by the two N atoms and two O atoms by 0.1017 Å,. The coordination geometry of the Cu^II ion is square-pyramidal. The Cu—N, Cu—O and Cu—O_methanol bond lengths are consistent with the corresponding distances in aqua-(N,N'-ethylenebis(3-methoxysalicylaldiminato)-N,N',\ O,O')copper(II) (Saha, et al., 2007).

Experimental

The Schiff base ligand was synthesized by condensation of 4,5-dibromo-1,2-diaminobenzene and 2-hydroxy-benzaldehyde with the ratio 1:2 in ethanol. The synthesis of the title complex was carried out by reacting Cu(ClO₄)₂.6H₂O, and the schiff-base ligand (1:1, molar ratio) in methanol. After the stirring process was continued for about 10 min at room temperature, the mixture was filtered and the filtrate was allowed to partial evaporate in air for sevral days to produce crystals suitable for X-ray diffraction with a yield about 55%.