Dichlorido{8-[2-(dimethylamino)ethylamino]quinoline-κ3 N,N′,N′′}zinc

In the title complex, [ZnCl2(C13H17N3)], the coordination sphere of the zinc cation is distorted square pyramidal. The three N atoms of the N,N′,N′′-tridentate 8-[2-(dimethylamino)ethylamino]quinoline ligand and one chloride ion constitute a considerably distorted square base. The apical site is occupied by another chloride ion. The distortion from the ideal square-pyramidal geometry is manifested by the N—Zn—N angle of 133.25 (11)°. Like most square-pyramidal metal complexes, the zinc cation is displaced towards the apical chloride ion. In the crystal, molecules are linked by N—H⋯Cl interactions. This leads to the formation of chains of molecules parallel to the b-axis direction.

In the title complex, [ZnCl 2 (C 13 H 17 N 3 )], the coordination sphere of the zinc cation is distorted square pyramidal. The three N atoms of the N,N 0 ,N 00 -tridentate 8-[2-(dimethylamino)ethylamino]quinoline ligand and one chloride ion constitute a considerably distorted square base. The apical site is occupied by another chloride ion. The distortion from the ideal square-pyramidal geometry is manifested by the N-Zn-N angle of 133.25 (11) . Like most square-pyramidal metal complexes, the zinc cation is displaced towards the apical chloride ion. In the crystal, molecules are linked by N-HÁ Á ÁCl interactions. This leads to the formation of chains of molecules parallel to the b-axis direction.

Comment
Zinc is a biologically important element. Zinc, always present as a divalent cation in biological systems, is the second most abundant d-block metal ion in the human body after iron. The zinc cation; Zn +2 , is well known to play diverse roles in many serious biochemical reactions, (Xu et al., 2010;Jena & Manivannan, 2012). The zinc(II) ion, however, provides a number of coordination compounds because of its affinity towards different types of ligands and flexible coordination number ranging from two to eight. In zinc complexes, commonly found geometries are tetrahedral and octahedral. Sixcoordinate complexes may be octahedral or trigonal-prismatic. Among the less common five-coordinate complexes, trigonal-bipyramidal geometry predominates over square-pyramidal geometry (Dai & Canary, 2007). Herein, we report the synthesis and characterization of 8-[2-dimethylamino]ethylamino]quinoline ZnCl 2 ]. This complex was characterized by elemental analyses, mass spectroscopy, 1 H-NMR, and single-crystal X-ray structure determination techniques. The single-crystal structure analysis of the complex reveals that the three nitrogen atoms of the tridentate ligand, N,N′,N′′, along with two chloride ions form a distorted square-pyramidal geometry around the zinc cation (  (Table 1). This leads to the formation of chains of molecules parallel to the b axis (Fig. 2).

Experimental
To a stirred methanoic solution (30 ml) of zinc dichloride (0.273 g m; 0.002 mol) kept under a positive nitrogen pressure, a methanoic solution (10 ml) containing an equimolar amount of the ligand (NN′N"); (0.43 g m; 0.002 mol) was slowly added. The resulting off white slurry was stirred at R·T. for 3 hrs. Then, the off white solid was collected by filtration, washed with smaller amount of cold methanol (5 ml, twice) followed by diethyl ether (15 ml, twice).the isolated solid

Refinement
The N-and C-bound H atoms were geometrically placed (X-H = 0.95-0.99Å where X is N or C atom) and refined using a riding model with U iso (H) = 1.2-1.5U eq (X).

Figure 1
The asymmetric of (I) with atom labels and 50% probability displacement ellipsoids.

Dichlorido{8-[2-(dimethylamino)ethylamino]quinoline-κ 3 N,N′,N′′}zinc
Crystal data  where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.31 e Å −3 Δρ min = −0.38 e Å −3 Absolute structure: Flack (1983), 873 Friedel pairs Absolute structure parameter: −0.002 (15) Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.