metal-organic compounds
Dichlorido(2-{[2-(piperazin-4-ium-1-yl)ethyl]iminomethyl}phenolate)cadmium(II)
aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: khaledi@siswa.um.edu.my
In the title compound, [CdCl2(C13H19N3O)], the CdII ion is pentacoordinated with the N,N,O-tridentate Schiff base 2-{[2-(piperazin-4-ium-1-yl)ethyl]iminomethyl}phenolate ligand and two Cl atoms in a highly distorted square-pyramidal geometry; the piperazine ring adopts a chair conformation. In the adjacent molecules are linked together via N—H⋯O and N—H⋯Cl hydrogen bonds, forming infinite layers parallel to the ab plane. The layers are further connected through C—H⋯Cl interactions into a three-dimensional network.
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell 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).
Supporting information
https://doi.org/10.1107/S1600536810032563/pv2318sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810032563/pv2318Isup2.hkl
The Schiff base ligand was prepared following the procedure reported previously (Mukhopadhyay et al., 2003). The cadmium (II) complex was synthesized by treatment of the ligand (0.233 g, 1 mmol) with cadmium (II) chloride (0.183 g, 1 mmol) in ethanol (20 ml). The mixture was stirred at room temperature for 10 min and then set aside for a few days whereupon the yellow crystals of the title compound were obtained.
The C-bound hydrogen atoms were placed at idealized positions (C—H = 0.95–0.99 Å) and were treated as riding on their parent atoms. The N-bound hydrogen atoms were located in a difference Fourier map and refined with distance restraint of N—H 0.88 (2) Å. The Uiso(H) were allowed at 1.2Ueq(C) or 1.5Ueq(N). The final difference map was essentially featurless.
The title compound is a cadmium (II) complex of the Schiff base ligand, 1-(2-salicylaldiminoethyl)piperazine. The piperazinyl arm of the ligand can, in principle, have both boat and chair conformations that makes the molecule to display ambidentate coordination behavior. The ligand has been shown to act as a tetradentate or tridentate chelate with nickel(II) ions, depending on the piperazine ring conformation (Mukhopadhyay et al., 2003). In the title complex, the piperazine ring adopts the chair conformation and the ligand is bound to the metal ion in a NNO-tridentate fashion. The cadmium(II) atom is penta-coordinated by the Schiff base ligand and two chloride atoms in a highly distorted square planar geometry (index τ = 0.38). The piperzaine nitrogen atom, N3, which stays away from coordination, is protonated, implying the zwitterionic nature of the complex. In the intermolecular N—H···O, N—H···Cl and C—H···Cl hydrogen bonds connect the adjacent molecules into infinite three-dimensional network (Fig. 2). Morever, intramolecular C—H···Cl hydrogen bondings are observed. The contains void spaces with the size of 199 Å-3 (6.2% of the cell volume) within which there is no evidence for included solvent.
For related structures, see: Mukhopadhyay et al. (2003); Xu et al. (2008).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 (Sheldrick, 2008) and publCIF (Westrip, 2010).Fig. 1. Displacement ellipsoid plot of the title compound at the 50% probability level. H atoms are drawn as spheres of arbitrary radius. | |
Fig. 2. Unit-cell packing of the title compound, viewed down the b axis, showing the hydrogen-bonded polymeric network. H atoms not involved in hydrogen bonds have been omitted for clarity. |
[CdCl2(C13H19N3O)] | F(000) = 1664 |
Mr = 416.61 | Dx = 1.718 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 9877 reflections |
a = 14.7512 (16) Å | θ = 2.4–31.3° |
b = 13.1406 (15) Å | µ = 1.69 mm−1 |
c = 16.6188 (19) Å | T = 100 K |
V = 3221.4 (6) Å3 | Block, yellow |
Z = 8 | 0.45 × 0.39 × 0.18 mm |
Bruker APEXII CCD diffractometer | 3700 independent reflections |
Radiation source: fine-focus sealed tube | 3409 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
φ and ω scans | θmax = 27.5°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −19→19 |
Tmin = 0.518, Tmax = 0.751 | k = −17→17 |
38841 measured reflections | l = −21→21 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.017 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.045 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0187P)2 + 2.1332P] where P = (Fo2 + 2Fc2)/3 |
3700 reflections | (Δ/σ)max = 0.002 |
187 parameters | Δρmax = 0.44 e Å−3 |
2 restraints | Δρmin = −0.28 e Å−3 |
[CdCl2(C13H19N3O)] | V = 3221.4 (6) Å3 |
Mr = 416.61 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 14.7512 (16) Å | µ = 1.69 mm−1 |
b = 13.1406 (15) Å | T = 100 K |
c = 16.6188 (19) Å | 0.45 × 0.39 × 0.18 mm |
Bruker APEXII CCD diffractometer | 3700 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 3409 reflections with I > 2σ(I) |
Tmin = 0.518, Tmax = 0.751 | Rint = 0.041 |
38841 measured reflections |
R[F2 > 2σ(F2)] = 0.017 | 2 restraints |
wR(F2) = 0.045 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.44 e Å−3 |
3700 reflections | Δρmin = −0.28 e Å−3 |
187 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Cd1 | 0.915609 (7) | 0.521115 (8) | 0.335271 (6) | 0.01335 (4) | |
Cl1 | 0.80478 (3) | 0.46142 (3) | 0.23256 (2) | 0.02000 (8) | |
Cl2 | 1.05575 (2) | 0.57074 (3) | 0.26583 (2) | 0.01803 (8) | |
O1 | 0.98159 (7) | 0.37354 (9) | 0.37625 (7) | 0.0192 (2) | |
N1 | 0.87369 (9) | 0.52146 (10) | 0.46665 (8) | 0.0162 (3) | |
N2 | 0.83315 (8) | 0.68754 (10) | 0.35360 (8) | 0.0139 (2) | |
N3 | 0.88695 (9) | 0.83051 (10) | 0.22922 (8) | 0.0149 (2) | |
H3A | 0.8533 (12) | 0.8859 (13) | 0.2359 (11) | 0.022* | |
H3B | 0.9244 (12) | 0.8437 (16) | 0.1887 (11) | 0.022* | |
C1 | 0.95272 (10) | 0.31114 (12) | 0.43163 (9) | 0.0169 (3) | |
C2 | 0.96780 (11) | 0.20498 (12) | 0.42363 (10) | 0.0195 (3) | |
H2 | 0.9967 | 0.1802 | 0.3765 | 0.023* | |
C3 | 0.94174 (11) | 0.13662 (13) | 0.48221 (10) | 0.0220 (3) | |
H3 | 0.9523 | 0.0660 | 0.4742 | 0.026* | |
C4 | 0.90004 (11) | 0.16929 (13) | 0.55317 (10) | 0.0213 (3) | |
H4 | 0.8837 | 0.1221 | 0.5940 | 0.026* | |
C5 | 0.88317 (10) | 0.27220 (13) | 0.56245 (9) | 0.0194 (3) | |
H5 | 0.8550 | 0.2953 | 0.6105 | 0.023* | |
C6 | 0.90643 (10) | 0.34411 (12) | 0.50271 (9) | 0.0167 (3) | |
C7 | 0.87494 (10) | 0.44702 (13) | 0.51703 (9) | 0.0172 (3) | |
H7 | 0.8527 | 0.4611 | 0.5695 | 0.021* | |
C8 | 0.83000 (10) | 0.61616 (12) | 0.49269 (9) | 0.0178 (3) | |
H8A | 0.8766 | 0.6657 | 0.5100 | 0.021* | |
H8B | 0.7895 | 0.6024 | 0.5389 | 0.021* | |
C9 | 0.77532 (10) | 0.66006 (12) | 0.42318 (9) | 0.0172 (3) | |
H9A | 0.7296 | 0.6095 | 0.4058 | 0.021* | |
H9B | 0.7426 | 0.7214 | 0.4419 | 0.021* | |
C10 | 0.88602 (10) | 0.77994 (12) | 0.37278 (9) | 0.0164 (3) | |
H10A | 0.9254 | 0.7662 | 0.4198 | 0.020* | |
H10B | 0.8440 | 0.8357 | 0.3874 | 0.020* | |
C11 | 0.94408 (10) | 0.81319 (12) | 0.30220 (9) | 0.0158 (3) | |
H11A | 0.9765 | 0.8768 | 0.3162 | 0.019* | |
H11B | 0.9899 | 0.7602 | 0.2906 | 0.019* | |
C12 | 0.82875 (10) | 0.74064 (12) | 0.21146 (9) | 0.0166 (3) | |
H12A | 0.8674 | 0.6825 | 0.1954 | 0.020* | |
H12B | 0.7878 | 0.7567 | 0.1660 | 0.020* | |
C13 | 0.77292 (10) | 0.71146 (12) | 0.28467 (9) | 0.0158 (3) | |
H13A | 0.7321 | 0.7684 | 0.2992 | 0.019* | |
H13B | 0.7350 | 0.6514 | 0.2719 | 0.019* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.01279 (7) | 0.01314 (7) | 0.01412 (7) | 0.00111 (4) | 0.00214 (4) | 0.00129 (4) |
Cl1 | 0.01838 (18) | 0.01817 (18) | 0.02346 (19) | −0.00298 (14) | −0.00124 (14) | −0.00369 (14) |
Cl2 | 0.01453 (16) | 0.01461 (17) | 0.02495 (19) | −0.00003 (13) | 0.00517 (14) | 0.00176 (14) |
O1 | 0.0201 (5) | 0.0189 (5) | 0.0186 (5) | 0.0057 (4) | 0.0045 (4) | 0.0040 (4) |
N1 | 0.0132 (6) | 0.0189 (7) | 0.0164 (6) | 0.0015 (5) | 0.0010 (5) | −0.0002 (5) |
N2 | 0.0117 (6) | 0.0146 (6) | 0.0153 (6) | −0.0007 (5) | 0.0005 (5) | 0.0009 (5) |
N3 | 0.0153 (6) | 0.0127 (6) | 0.0166 (6) | −0.0006 (5) | 0.0005 (5) | 0.0007 (5) |
C1 | 0.0134 (7) | 0.0180 (7) | 0.0192 (7) | 0.0003 (6) | −0.0030 (6) | 0.0024 (6) |
C2 | 0.0174 (7) | 0.0190 (8) | 0.0222 (8) | 0.0013 (6) | −0.0020 (6) | 0.0017 (6) |
C3 | 0.0178 (7) | 0.0175 (8) | 0.0306 (9) | −0.0017 (6) | −0.0083 (6) | 0.0054 (7) |
C4 | 0.0167 (7) | 0.0244 (8) | 0.0229 (8) | −0.0052 (6) | −0.0065 (6) | 0.0098 (7) |
C5 | 0.0147 (7) | 0.0273 (8) | 0.0161 (7) | −0.0045 (6) | −0.0034 (6) | 0.0050 (6) |
C6 | 0.0143 (7) | 0.0198 (8) | 0.0158 (7) | −0.0019 (6) | −0.0024 (6) | 0.0034 (6) |
C7 | 0.0128 (7) | 0.0241 (8) | 0.0147 (7) | −0.0013 (6) | 0.0000 (5) | 0.0003 (6) |
C8 | 0.0183 (7) | 0.0195 (7) | 0.0156 (7) | 0.0017 (6) | 0.0035 (6) | −0.0006 (6) |
C9 | 0.0139 (7) | 0.0179 (7) | 0.0198 (7) | 0.0011 (6) | 0.0040 (6) | 0.0009 (6) |
C10 | 0.0153 (7) | 0.0168 (7) | 0.0172 (7) | −0.0021 (6) | 0.0004 (6) | −0.0023 (6) |
C11 | 0.0139 (7) | 0.0155 (7) | 0.0179 (7) | −0.0019 (6) | −0.0009 (6) | 0.0003 (6) |
C12 | 0.0164 (7) | 0.0157 (7) | 0.0177 (7) | −0.0023 (6) | −0.0025 (6) | −0.0004 (6) |
C13 | 0.0124 (7) | 0.0157 (7) | 0.0192 (7) | −0.0007 (5) | −0.0020 (6) | 0.0009 (6) |
Cd1—N1 | 2.2693 (13) | C4—C5 | 1.384 (2) |
Cd1—O1 | 2.2740 (11) | C4—H4 | 0.9500 |
Cd1—Cl2 | 2.4557 (4) | C5—C6 | 1.413 (2) |
Cd1—Cl1 | 2.4904 (4) | C5—H5 | 0.9500 |
Cd1—N2 | 2.5209 (13) | C6—C7 | 1.450 (2) |
O1—C1 | 1.3042 (19) | C7—H7 | 0.9500 |
N1—C7 | 1.288 (2) | C8—C9 | 1.522 (2) |
N1—C8 | 1.4667 (19) | C8—H8A | 0.9900 |
N2—C10 | 1.4779 (19) | C8—H8B | 0.9900 |
N2—C9 | 1.4816 (19) | C9—H9A | 0.9900 |
N2—C13 | 1.4833 (19) | C9—H9B | 0.9900 |
N3—C12 | 1.4897 (19) | C10—C11 | 1.517 (2) |
N3—C11 | 1.4943 (19) | C10—H10A | 0.9900 |
N3—H3A | 0.889 (15) | C10—H10B | 0.9900 |
N3—H3B | 0.887 (15) | C11—H11A | 0.9900 |
C1—C2 | 1.419 (2) | C11—H11B | 0.9900 |
C1—C6 | 1.432 (2) | C12—C13 | 1.518 (2) |
C2—C3 | 1.379 (2) | C12—H12A | 0.9900 |
C2—H2 | 0.9500 | C12—H12B | 0.9900 |
C3—C4 | 1.398 (3) | C13—H13A | 0.9900 |
C3—H3 | 0.9500 | C13—H13B | 0.9900 |
N1—Cd1—O1 | 80.22 (4) | C5—C6—C7 | 115.51 (14) |
N1—Cd1—Cl2 | 132.92 (3) | C1—C6—C7 | 124.80 (14) |
O1—Cd1—Cl2 | 90.39 (3) | N1—C7—C6 | 127.33 (14) |
N1—Cd1—Cl1 | 118.77 (3) | N1—C7—H7 | 116.3 |
O1—Cd1—Cl1 | 102.57 (3) | C6—C7—H7 | 116.3 |
Cl2—Cd1—Cl1 | 108.309 (15) | N1—C8—C9 | 109.30 (12) |
N1—Cd1—N2 | 75.55 (4) | N1—C8—H8A | 109.8 |
O1—Cd1—N2 | 155.52 (4) | C9—C8—H8A | 109.8 |
Cl2—Cd1—N2 | 103.45 (3) | N1—C8—H8B | 109.8 |
Cl1—Cd1—N2 | 92.25 (3) | C9—C8—H8B | 109.8 |
C1—O1—Cd1 | 127.43 (9) | H8A—C8—H8B | 108.3 |
C7—N1—C8 | 117.32 (13) | N2—C9—C8 | 112.31 (12) |
C7—N1—Cd1 | 128.33 (11) | N2—C9—H9A | 109.1 |
C8—N1—Cd1 | 113.90 (9) | C8—C9—H9A | 109.1 |
C10—N2—C9 | 109.61 (12) | N2—C9—H9B | 109.1 |
C10—N2—C13 | 107.97 (12) | C8—C9—H9B | 109.1 |
C9—N2—C13 | 108.04 (11) | H9A—C9—H9B | 107.9 |
C10—N2—Cd1 | 118.96 (9) | N2—C10—C11 | 111.59 (12) |
C9—N2—Cd1 | 99.25 (9) | N2—C10—H10A | 109.3 |
C13—N2—Cd1 | 112.30 (9) | C11—C10—H10A | 109.3 |
C12—N3—C11 | 111.41 (12) | N2—C10—H10B | 109.3 |
C12—N3—H3A | 110.6 (13) | C11—C10—H10B | 109.3 |
C11—N3—H3A | 109.8 (12) | H10A—C10—H10B | 108.0 |
C12—N3—H3B | 111.3 (14) | N3—C11—C10 | 110.68 (12) |
C11—N3—H3B | 107.1 (13) | N3—C11—H11A | 109.5 |
H3A—N3—H3B | 106.4 (19) | C10—C11—H11A | 109.5 |
O1—C1—C2 | 120.06 (14) | N3—C11—H11B | 109.5 |
O1—C1—C6 | 123.22 (14) | C10—C11—H11B | 109.5 |
C2—C1—C6 | 116.72 (14) | H11A—C11—H11B | 108.1 |
C3—C2—C1 | 122.04 (16) | N3—C12—C13 | 110.73 (12) |
C3—C2—H2 | 119.0 | N3—C12—H12A | 109.5 |
C1—C2—H2 | 119.0 | C13—C12—H12A | 109.5 |
C2—C3—C4 | 121.21 (16) | N3—C12—H12B | 109.5 |
C2—C3—H3 | 119.4 | C13—C12—H12B | 109.5 |
C4—C3—H3 | 119.4 | H12A—C12—H12B | 108.1 |
C5—C4—C3 | 118.25 (15) | N2—C13—C12 | 110.34 (12) |
C5—C4—H4 | 120.9 | N2—C13—H13A | 109.6 |
C3—C4—H4 | 120.9 | C12—C13—H13A | 109.6 |
C4—C5—C6 | 122.12 (15) | N2—C13—H13B | 109.6 |
C4—C5—H5 | 118.9 | C12—C13—H13B | 109.6 |
C6—C5—H5 | 118.9 | H13A—C13—H13B | 108.1 |
C5—C6—C1 | 119.56 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···Cl1i | 0.89 (2) | 2.53 (2) | 3.3108 (14) | 146 (2) |
N3—H3A···Cl2ii | 0.89 (2) | 2.78 (2) | 3.2689 (14) | 116 (2) |
N3—H3B···O1ii | 0.89 (2) | 1.80 (2) | 2.6743 (17) | 167 (2) |
C11—H11B···Cl2 | 0.99 | 2.70 | 3.6372 (16) | 157 |
C13—H13B···Cl1 | 0.99 | 2.78 | 3.4302 (16) | 124 |
C4—H4···Cl1iii | 0.95 | 2.80 | 3.7165 (17) | 161 |
C13—H13A···Cl1i | 0.99 | 2.82 | 3.5851 (16) | 134 |
Symmetry codes: (i) −x+3/2, y+1/2, z; (ii) −x+2, y+1/2, −z+1/2; (iii) x, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [CdCl2(C13H19N3O)] |
Mr | 416.61 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 100 |
a, b, c (Å) | 14.7512 (16), 13.1406 (15), 16.6188 (19) |
V (Å3) | 3221.4 (6) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 1.69 |
Crystal size (mm) | 0.45 × 0.39 × 0.18 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.518, 0.751 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 38841, 3700, 3409 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.017, 0.045, 1.06 |
No. of reflections | 3700 |
No. of parameters | 187 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.44, −0.28 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), X-SEED (Barbour, 2001), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···Cl1i | 0.889 (15) | 2.534 (16) | 3.3108 (14) | 146.4 (17) |
N3—H3A···Cl2ii | 0.889 (15) | 2.775 (19) | 3.2689 (14) | 116.4 (15) |
N3—H3B···O1ii | 0.887 (15) | 1.802 (15) | 2.6743 (17) | 167.4 (19) |
C11—H11B···Cl2 | 0.99 | 2.70 | 3.6372 (16) | 157.4 |
C13—H13B···Cl1 | 0.99 | 2.78 | 3.4302 (16) | 123.9 |
C4—H4···Cl1iii | 0.95 | 2.80 | 3.7165 (17) | 161.2 |
C13—H13A···Cl1i | 0.99 | 2.82 | 3.5851 (16) | 134.4 |
Symmetry codes: (i) −x+3/2, y+1/2, z; (ii) −x+2, y+1/2, −z+1/2; (iii) x, −y+1/2, z+1/2. |
Acknowledgements
The authors thank the University of Malaya for funding this study (FRGS grant No. FP009/2008 C).
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The title compound is a cadmium (II) complex of the Schiff base ligand, 1-(2-salicylaldiminoethyl)piperazine. The piperazinyl arm of the ligand can, in principle, have both boat and chair conformations that makes the molecule to display ambidentate coordination behavior. The ligand has been shown to act as a tetradentate or tridentate chelate with nickel(II) ions, depending on the piperazine ring conformation (Mukhopadhyay et al., 2003). In the title complex, the piperazine ring adopts the chair conformation and the ligand is bound to the metal ion in a NNO-tridentate fashion. The cadmium(II) atom is penta-coordinated by the Schiff base ligand and two chloride atoms in a highly distorted square planar geometry (index τ = 0.38). The piperzaine nitrogen atom, N3, which stays away from coordination, is protonated, implying the zwitterionic nature of the complex. In the crystal structure, intermolecular N—H···O, N—H···Cl and C—H···Cl hydrogen bonds connect the adjacent molecules into infinite three-dimensional network (Fig. 2). Morever, intramolecular C—H···Cl hydrogen bondings are observed. The crystal structure contains void spaces with the size of 199 Å-3 (6.2% of the cell volume) within which there is no evidence for included solvent.