Dibromido{N′-[1-(pyridin-2-yl)ethyl­idene]picolinohydrazide-κ2 N′,O}cadmium

Mehmet Akkurt; Ali Akbar Khandar; Muhammad Nawaz Tahir; Seyed Abolfazl Hosseini Yazdi; Farhad Akbari Afkhami

doi:10.1107/S1600536812023185

. 2012 May 31;68(Pt 6):m842. doi: 10.1107/S1600536812023185

Dibromido{N′-[1-(pyridin-2-yl)ethylidene]picolinohydrazide-κ² N′,O}cadmium

Mehmet Akkurt ^a,^*, Ali Akbar Khandar ^b, Muhammad Nawaz Tahir ^c, Seyed Abolfazl Hosseini Yazdi ^b, Farhad Akbari Afkhami ^b

PMCID: PMC3379182 PMID: 22719380

Abstract

The title compound, [CdBr₂(C₁₃H₁₂N₄O)], was obtained from the reaction of Cd(NO₃)₂·4H₂O with methyl(pyridin-2-yl)methanone picolinoylhydrazone and sodium bromide. The Cd²⁺ cation is ligated by one O atom and two N atoms of the tridentate ligand and two bromide anions, forming a Br₂CdN₂O polyhedron with a distorted trigonal–bipyramidal coordination geometry. In the crystal, non-classical C—H⋯Br hydrogen bonds are observed. In addition, π–π stacking interactions [centroid–centroid distance = 3.7455 (19) Å] contribute to the stabilization of the crystal structure.

Related literature

For related complexes with similar tridentate ligands, see: Kasuga et al. (2001 ▶); Chen et al. (2005 ▶); Datta et al. (2011 ▶). graphic file with name e-68-0m842-scheme1.jpg

Experimental

Crystal data

[CdBr₂(C₁₃H₁₂N₄O)]
M _r = 512.48
Monoclinic,
a = 8.1336 (3) Å
b = 13.6111 (5) Å
c = 14.6102 (5) Å
β = 90.550 (1)°
V = 1617.38 (10) Å³
Z = 4
Mo Kα radiation
μ = 6.29 mm⁻¹
T = 296 K
0.32 × 0.18 × 0.16 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.267, T _max = 0.365
15317 measured reflections
3874 independent reflections
2859 reflections with I > 2σ(I)
R _int = 0.032

Refinement

R[F ² > 2σ(F ²)] = 0.028
wR(F ²) = 0.062
S = 1.02
3874 reflections
195 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.54 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); 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 datablock(s) global, I. DOI: 10.1107/S1600536812023185/vm2176sup1.cif

e-68-0m842-sup1.cif^{(24.7KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812023185/vm2176Isup2.hkl

e-68-0m842-Isup2.hkl^{(189.9KB, 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
C7—H7C⋯Br2ⁱ	0.96	2.91	3.810 (4)	157

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Symmetry code: (i) Inline graphic .

Acknowledgments

The authors acknowledge the provision of funds for the purchase of a diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.

supplementary crystallographic information

Comment

Schiff base complexes have attracted much attention due to their interesting structures and wide potential applications. Recently, the relative unsymmetrical tridentate Schiff base ligands and their hydrogenated derivatives have been introduced into the coordination chemistry to assemble polymers with beautiful molecular structures. Some organic N-donor ligands are often chosen to fabricate these various complexes. In this connection, some complexes with similar tridentate ligands have been studied (Kasuga et al., 2001; Chen et al., 2005; Datta et al., 2011). Herein, we report the structure of a new cadmium complex based on a pyridine based tridentate Schiff base ligand.

The molecular structure of title compound is shown in Fig. 1. The Cd ion is five coordinated forming a distorted trigonal-bipyramidal coordination sphere, in which three positions are occupied by two N atoms and one O atom from the tridentate Schiff base ligand, and two positions coming from two bromide ions. As can be seen in Fig. 1, all non-H atoms of the tridentate Schiff base ligand are nearly coplanar, with maximum deviations of -0.053 (4) Å for C7 and 0.049 (2) Å for N2.

Molecules are linked to each other, via weak C—H···Br intermolecular hydrogen bonds along the crystallographic a axis (Table 1, Fig. 2). In the crystal, weak π-π stacking interactions also contribute to the stabilization: [Cg3···Cg3(1 - x, -y, 1 - z) = 3.7455 (19) Å; where Cg3 is the centroid of the N1/C1–C5 ring].

Experimental

The potentially tridenatate ligand methyl-2-pyridyl ketone picolinoyl hydrazone was obtained by condensation of methyl-2-pyridyl ketone and picolinic acid hydrazide with the ratio 1:1 in methanol. The title compound C₁₃H₁₂Br₂CdN₄O has been synthesized by the reaction of methanolic solution of the ligand and Cd(NO₃)₂.4H₂O in the presence of excess amount of NaBr. The ligand (1 mmol, 0.240 g) and cadmium nitrate (1 mmol, 279 g) were placed in main arm of a branched tube; sodium bromide (2 mmol, 0.206 g) was added to the mixture too. Methanol was carefully added to fill the arms. The tube was sealed and the ligand-containing arm was immersed in an oil bath at 333 K while the branched arm was kept at ambient temperature. After five days, suitable single crystals, were deposited in the cooler arm which were isolated, filtered off, washed with acetone and ether and air dried.