Dichlorido(4-methoxy-2-{[2-(piperazin-4-ium-1-yl)ethyl]iminomethyl}phenolate)cadmium

In the title compound, [CdCl2(C14H21N3O2)], the Schiff base ligand chelates the CdII ion in an N,N,O-tridentate fashion. Two Cl atoms complete a distorted square-pyramidal coordination environment around the metal atom. In the crystal, adjacent molecules are linked through C—H⋯π interactions into infinite chains along the a axis. The molecules are further connected into a three-dimensional network via N—H⋯O, N—H⋯Cl and C—H⋯Cl interactions. The ethylene group is disordered over two sets of sites in a 0.520 (10):0.480 (10) ratio.

In the title compound, [CdCl 2 (C 14 H 21 N 3 O 2 )], the Schiff base ligand chelates the Cd II ion in an N,N,O-tridentate fashion. Two Cl atoms complete a distorted square-pyramidal coordination environment around the metal atom. In the crystal, adjacent molecules are linked through C-HÁ Á Á interactions into infinite chains along the a axis. The molecules are further connected into a three-dimensional network via N-HÁ Á ÁO, N-HÁ Á ÁCl and C-HÁ Á ÁCl interactions. The ethylene group is disordered over two sets of sites in a 0.520 (10):0.480 (10) ratio.

D-HÁ
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: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2010). metal atom in an N,N,O-mode, along with two Cl atoms makes a distorted square-pyramidal cadmium(II) complex. The distortion from the ideal geometry is evident from the τ index of 0.30 (τ is 0 for an ideal square-pyramid and is 1 for a perfect trigonal-bipyramid, Addison et al., 1984). The other ring N atom stays away from the chelation, and is protonated to keep the electronutrality of the molecule, thus the complex can be described as a zwitterion. In the crystal, C-H···π interactions link the molecules into infinite chains along the a axis and these are connected into a three-dimensional network via N-H···O, N-H···Cl and C-H···Cl hydrogen bonds (Table 1).

Experimental
A mixture of 5-methoxysalicylaldehyde (0.35 g, 2.3 mmol) and aminoethylpiperazine (0.3 g, 2.3 mmol) in ethanol (20 ml) was refluxed for 2 h, followed by addition of a solution of cadmium(II) chloride (0.42 g, 2.3 mmol) in a minimum amount of ethanol. The resulting solution was refluxed for 1 h and then left at room temperature for one day to give the X-ray quality crystals of the title compound.

Refinement
The C-bound hydrogen atoms were placed at calculated positions and refined as riding atoms with C-H distances of 0.95 (aryl), 0.98 (methyl) and 0.99 Å (methylene). The N-bound hydrogen atoms were located in a difference Fourier map and refined with distance restraint of N-H 0.91 (2) Å. For all hydrogen atoms Uiso(H) were set to 1.2 (1.5 for methyl)Ueq(carrier atom). C9 and C10 were found to be disordered with two positions being resolved for each of the atoms.
From anisotropic refinement, the site occupancy factor of the major component refined is 0.52 (1). The corresponding bond distances involving the disordered atoms were restrained to be equal with the SADI command in SHELXL97 (Sheldrick, 2008). Fig. 1. Thermal ellipsoid plot of the title compound at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius. Only the major disordered component is shown.