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Acta Crystallogr Sect E Struct Rep Online. 2009 December 1; 65(Pt 12): m1685–m1686.
Published online 2009 November 28. doi:  10.1107/S1600536809049800
PMCID: PMC2971750

Bis[μ-4,4′,6,6′-tetra­chloro-2,2′-(piperazine-1,4-diyldimethyl­ene)diphenolato]dicopper(II)

Abstract

In the centrosymmetric dinuclear CuII title complex, [Cu2(C18H16Cl4N2O2)2], the CuII atom adopts a square-pyramidal geometry with a tetra­dentate ligand in the basal plane. The apical site is occupied by a phenolate O atom from an adjacent ligand, forming a dimer. The mol­ecular structure is stabilized by intra­molecular C—H(...)O and C—H(...)Cl hydrogen bonds.

Related literature

For the synthesis and the monoclinic and ortho­rhom­bic polymorphs of a tetra­chloro-2,2′-(piperazine-1,4-diyldi­methyl­ene)diphenol, see: Kubono & Yokoi (2007 [triangle]). For related stuctures, see: Butcher et al. (2007 [triangle]); Kubono et al. (2003 [triangle]); Massoud & Mautner (2004 [triangle]); Weinberger et al. (2000 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-m1685-scheme1.jpg

Experimental

Crystal data

  • [Cu2(C18H16Cl4N2O2)2]
  • M r = 995.36
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-m1685-efi2.jpg
  • a = 20.1772 (18) Å
  • b = 15.3901 (18) Å
  • c = 15.1397 (14) Å
  • β = 121.140 (6)°
  • V = 4023.9 (7) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 1.63 mm−1
  • T = 296 K
  • 0.20 × 0.08 × 0.07 mm

Data collection

  • Rigaku AFC-7R diffractometer
  • Absorption correction: ψ scan (North et al., 1968 [triangle]) T min = 0.855, T max = 0.892
  • 4759 measured reflections
  • 4634 independent reflections
  • 2574 reflections with I > 2σ(I)
  • R int = 0.046
  • 3 standard reflections every 150 reflections intensity decay: 0.7%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.041
  • wR(F 2) = 0.119
  • S = 0.99
  • 4634 reflections
  • 245 parameters
  • H-atom parameters constrained
  • Δρmax = 0.37 e Å−3
  • Δρmin = −0.39 e Å−3

Data collection: WinAFC (Rigaku/MSC, 2006 [triangle]); cell refinement: WinAFC; data reduction: CrystalStructure (Rigaku/MSC, 2006 [triangle]); program(s) used to solve structure: SIR92 (Altomare et al., 1993 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: CrystalStructure.

Table 1
Selected geometric parameters (Å, °)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809049800/fk2007sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809049800/fk2007Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This study was supported financially in part by Grants-in-Aid (No. 20550075) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.

supplementary crystallographic information

Comment

Recently, we have reported the crystal structure of tetrachloro-2,2'-(piperazine-1,4-diyldimethylene)diphenol, H2Cl2bpi (Kubono & Yokoi, 2007). As a continuation of this work on the structural characterization of piperazinediphenol compounds, the title dinuclear CuII complex (Fig. 1) is reported here. The CuII atom has a square-pyramidal coordination geometry with the basal plane comprised of two phenolate O and two tertiary alkyl N atoms from a piperazinediphenol ligand. The apical site is occupied by a phenolate O atom from an adjacent ligand generated by inversion operation, building a centrosymmetric dimer. The Cu···Cu distance within the dimer is 3.1883 (10) Å. The dihedral angle between the benzene rings (C1–C6 and C13–C18) is 87.96 (16) °. The coordination bond lengths and angles (Table 1) are comparable to those observed in related complexes (Butcher et al., 2007; Kubono et al., 2003; Massoud et al., 2004; Weinberger et al., 2000). The molecular structure complex is stabilized by intramolecular C—H···O and C—H···Cl hydrogen bonds (Table 2).

Experimental

H2Cl2bpi (0.109 g, 0.25 mmol) was dissolved in 30 ml hot chloroform. Then 30 ml of a methanol solution of copper acetate monohydrate (0.0499 g, 0.25 mmol) were added to this solution. The mixture was stirred for 20 min at 340 K. After a few days at room temperature, dark-green crystals of (I) were obtained. Yield 24.4%. Analysis calculated for C36H32Cl8Cu2N4O4: C 43.44, H 3.24, N 5.63%; found: C 43.05, H 3.22, N 5.53%.

Refinement

All H atoms were placed at idealized positions and refined as a riding atoms, with C—H = 0.93–0.97Å and Uiso(H) = 1.2 Ueq(C).

Figures

Fig. 1.
The molecule of the title complex showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 40% probability level. Only the H atoms involved in the hydrogen bonds are represented by circles of arbitrary size. [Symmetry code: (i) 1/2 ...

Crystal data

[Cu2(C18H16Cl4N2O2)2]F(000) = 2008.00
Mr = 995.36Dx = 1.643 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71069 Å
Hall symbol: -C 2ycCell parameters from 25 reflections
a = 20.1772 (18) Åθ = 13.4–14.9°
b = 15.3901 (18) ŵ = 1.63 mm1
c = 15.1397 (14) ÅT = 296 K
β = 121.140 (6)°Column, dark-green
V = 4023.9 (7) Å30.20 × 0.08 × 0.07 mm
Z = 4

Data collection

Rigaku AFC-7R diffractometerRint = 0.046
ω–2θ scansθmax = 27.5°
Absorption correction: ψ scan (North et al., 1968)h = 0→26
Tmin = 0.855, Tmax = 0.892k = 0→19
4759 measured reflectionsl = −19→16
4634 independent reflections3 standard reflections every 150 reflections
2574 reflections with I > 2σ(I) intensity decay: 0.7%

Refinement

Refinement on F2H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.041w = 1/[σ2(Fo2) + (0.0378P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.119(Δ/σ)max < 0.001
S = 0.99Δρmax = 0.37 e Å3
4634 reflectionsΔρmin = −0.39 e Å3
245 parameters

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Cu10.23572 (3)0.25394 (3)0.09411 (4)0.03688 (13)
Cl10.42437 (6)0.45428 (7)0.29614 (8)0.0506 (2)
Cl20.41605 (8)0.34818 (11)0.62836 (9)0.0812 (4)
Cl3−0.07156 (8)0.53920 (10)−0.17092 (12)0.0863 (4)
Cl40.23821 (7)0.53026 (7)0.00693 (10)0.0645 (3)
O10.33424 (16)0.29710 (19)0.1996 (2)0.0490 (7)
O20.21681 (15)0.33844 (16)−0.01288 (19)0.0391 (6)
N10.22348 (19)0.1741 (2)0.1911 (2)0.0421 (7)
N20.12414 (18)0.2118 (2)0.0166 (2)0.0381 (7)
C10.3513 (2)0.3070 (2)0.2952 (2)0.0384 (8)
C20.3933 (2)0.3796 (2)0.3535 (2)0.0356 (8)
C30.4129 (2)0.3920 (2)0.4540 (3)0.0427 (9)
C40.3895 (2)0.3322 (3)0.4996 (3)0.0497 (10)
C50.3496 (2)0.2591 (2)0.4474 (3)0.0498 (10)
C60.3311 (2)0.2455 (2)0.3472 (3)0.0421 (8)
C70.2937 (2)0.1606 (2)0.2929 (3)0.0494 (10)
C80.1593 (2)0.2145 (3)0.1957 (3)0.0550 (11)
C90.0965 (2)0.2379 (2)0.0862 (3)0.0498 (10)
C100.1323 (2)0.1156 (2)0.0214 (3)0.0493 (10)
C110.1958 (2)0.0924 (2)0.1308 (3)0.0509 (10)
C120.0751 (2)0.2445 (2)−0.0894 (3)0.0440 (9)
C130.0784 (2)0.3422 (2)−0.0909 (3)0.0435 (9)
C140.0111 (2)0.3904 (3)−0.1272 (3)0.0548 (11)
C150.0140 (2)0.4794 (3)−0.1254 (3)0.0582 (11)
C160.0832 (2)0.5220 (3)−0.0846 (3)0.0588 (12)
C170.1506 (2)0.4743 (2)−0.0473 (3)0.0474 (9)
C180.1510 (2)0.3828 (2)−0.0497 (3)0.0393 (8)
H10.44170.44030.49070.051*
H20.33500.21850.47970.060*
H30.33080.12720.28440.059*
H40.28050.12710.33590.059*
H50.17720.26620.23830.066*
H60.13910.17430.22550.066*
H70.04880.20760.06750.060*
H80.08650.29990.08080.060*
H90.14620.0957−0.02770.059*
H100.08390.08840.00490.059*
H110.17560.05350.16180.061*
H120.23810.06340.13000.061*
H130.02210.2259−0.11680.053*
H140.09290.2206−0.13290.053*
H15−0.03610.3622−0.15290.066*
H160.08490.5824−0.08200.070*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cu10.0394 (2)0.0371 (2)0.0428 (2)−0.0113 (2)0.0273 (2)−0.0080 (2)
Cl10.0544 (6)0.0427 (5)0.0575 (6)−0.0089 (4)0.0308 (5)−0.0021 (4)
Cl20.0865 (9)0.1165 (12)0.0375 (6)0.0042 (8)0.0298 (6)−0.0045 (7)
Cl30.0662 (8)0.0757 (9)0.0988 (11)0.0224 (7)0.0297 (7)−0.0121 (8)
Cl40.0670 (7)0.0423 (6)0.0935 (9)−0.0160 (5)0.0482 (7)−0.0237 (6)
O10.0489 (16)0.0635 (19)0.0403 (15)−0.0248 (14)0.0272 (13)−0.0149 (14)
O20.0414 (14)0.0367 (14)0.0448 (15)−0.0073 (12)0.0263 (12)−0.0059 (12)
N10.0474 (19)0.0402 (19)0.0470 (19)−0.0135 (14)0.0304 (16)−0.0111 (15)
N20.0384 (17)0.0362 (16)0.0497 (19)−0.0090 (14)0.0298 (16)−0.0095 (15)
C10.0337 (19)0.045 (2)0.037 (2)−0.0012 (16)0.0183 (16)−0.0034 (17)
C20.0314 (18)0.0345 (19)0.038 (2)0.0022 (15)0.0159 (16)−0.0009 (16)
C30.037 (2)0.039 (2)0.043 (2)0.0103 (17)0.0138 (18)−0.0039 (18)
C40.046 (2)0.064 (2)0.035 (2)0.015 (2)0.0181 (19)0.003 (2)
C50.046 (2)0.060 (2)0.046 (2)0.005 (2)0.025 (2)0.011 (2)
C60.043 (2)0.042 (2)0.045 (2)−0.0020 (19)0.0247 (18)−0.0021 (19)
C70.058 (2)0.040 (2)0.055 (2)−0.0046 (19)0.032 (2)0.0053 (19)
C80.054 (2)0.068 (3)0.059 (2)−0.009 (2)0.041 (2)−0.012 (2)
C90.049 (2)0.050 (2)0.068 (2)−0.004 (2)0.043 (2)−0.011 (2)
C100.045 (2)0.040 (2)0.066 (2)−0.0138 (18)0.031 (2)−0.016 (2)
C110.064 (2)0.031 (2)0.066 (2)−0.0147 (19)0.039 (2)−0.0104 (19)
C120.038 (2)0.045 (2)0.051 (2)−0.0141 (19)0.0248 (18)−0.017 (2)
C130.042 (2)0.046 (2)0.040 (2)−0.0026 (18)0.0205 (18)−0.0064 (18)
C140.040 (2)0.063 (3)0.057 (2)−0.006 (2)0.022 (2)−0.014 (2)
C150.055 (2)0.056 (2)0.055 (2)0.012 (2)0.023 (2)−0.007 (2)
C160.072 (3)0.039 (2)0.069 (3)−0.001 (2)0.038 (2)−0.009 (2)
C170.050 (2)0.043 (2)0.055 (2)−0.0035 (19)0.031 (2)−0.011 (2)
C180.045 (2)0.036 (2)0.040 (2)−0.0041 (17)0.0241 (18)−0.0073 (17)

Geometric parameters (Å, °)

Cu1—O11.913 (2)C10—C111.523 (5)
Cu1—O21.955 (2)C12—C131.505 (5)
Cu1—O2i2.381 (3)C13—C141.387 (6)
Cu1—N12.026 (4)C13—C181.408 (5)
Cu1—N22.033 (3)C14—C151.371 (6)
Cl1—C21.740 (4)C15—C161.368 (7)
Cl2—C41.751 (4)C16—C171.383 (6)
Cl3—C151.752 (5)C17—C181.409 (5)
Cl4—C171.744 (4)C3—H10.930
O1—C11.313 (5)C5—H20.930
O2—C181.332 (4)C7—H30.970
N1—C71.472 (4)C7—H40.970
N1—C81.470 (7)C8—H50.970
N1—C111.484 (5)C8—H60.970
N2—C91.479 (7)C9—H70.970
N2—C101.487 (4)C9—H80.970
N2—C121.472 (4)C10—H90.970
C1—C21.406 (4)C10—H100.970
C1—C61.419 (6)C11—H110.970
C2—C31.373 (6)C11—H120.970
C3—C41.372 (7)C12—H130.970
C4—C51.373 (5)C12—H140.970
C5—C61.378 (6)C14—H150.930
C6—C71.519 (5)C16—H160.930
C8—C91.521 (5)
O1—Cu1—O297.69 (11)C13—C14—C15120.3 (4)
O1—Cu1—O2i96.68 (12)Cl3—C15—C14119.7 (3)
O1—Cu1—N193.97 (12)Cl3—C15—C16119.6 (3)
O1—Cu1—N2162.75 (17)C14—C15—C16120.7 (4)
O2—Cu1—O2i85.84 (11)C15—C16—C17119.2 (4)
O2—Cu1—N1163.66 (13)Cl4—C17—C16118.3 (3)
O2—Cu1—N292.90 (12)Cl4—C17—C18119.2 (3)
O2i—Cu1—N1104.18 (13)C16—C17—C18122.5 (4)
O2i—Cu1—N297.64 (12)O2—C18—C13122.8 (3)
N1—Cu1—N273.22 (13)O2—C18—C17121.3 (3)
Cu1—O1—C1121.8 (3)C13—C18—C17115.9 (3)
Cu1—O2—Cu1i94.16 (10)C2—C3—H1120.4
Cu1—O2—C18114.4 (3)C4—C3—H1120.4
Cu1i—O2—C18132.1 (2)C4—C5—H2119.9
Cu1—N1—C7115.6 (3)C6—C5—H2119.9
Cu1—N1—C8102.7 (2)N1—C7—H3109.1
Cu1—N1—C11102.5 (2)N1—C7—H4109.1
C7—N1—C8113.9 (3)C6—C7—H3109.1
C7—N1—C11112.1 (2)C6—C7—H4109.1
C8—N1—C11109.0 (3)H3—C7—H4107.8
Cu1—N2—C9102.5 (2)N1—C8—H5110.1
Cu1—N2—C10103.1 (2)N1—C8—H6110.1
Cu1—N2—C12116.0 (2)C9—C8—H5110.1
C9—N2—C10107.9 (3)C9—C8—H6110.1
C9—N2—C12113.3 (3)H5—C8—H6108.4
C10—N2—C12112.8 (3)N2—C9—H7110.2
O1—C1—C2120.9 (4)N2—C9—H8110.2
O1—C1—C6123.2 (3)C8—C9—H7110.2
C2—C1—C6115.8 (3)C8—C9—H8110.2
Cl1—C2—C1117.9 (3)H7—C9—H8108.5
Cl1—C2—C3119.3 (2)N2—C10—H9110.3
C1—C2—C3122.7 (4)N2—C10—H10110.3
C2—C3—C4119.2 (3)C11—C10—H9110.3
Cl2—C4—C3118.7 (3)C11—C10—H10110.3
Cl2—C4—C5120.4 (4)H9—C10—H10108.5
C3—C4—C5120.8 (4)N1—C11—H11110.1
C4—C5—C6120.2 (4)N1—C11—H12110.1
C1—C6—C5121.2 (3)C10—C11—H11110.1
C1—C6—C7118.5 (4)C10—C11—H12110.1
C5—C6—C7120.2 (4)H11—C11—H12108.4
N1—C7—C6112.6 (3)N2—C12—H13109.6
N1—C8—C9107.8 (4)N2—C12—H14109.6
N2—C9—C8107.7 (3)C13—C12—H13109.6
N2—C10—C11107.3 (3)C13—C12—H14109.6
N1—C11—C10107.9 (3)H13—C12—H14108.1
N2—C12—C13110.3 (2)C13—C14—H15119.8
C12—C13—C14119.9 (3)C15—C14—H15119.8
C12—C13—C18118.8 (3)C15—C16—H16120.4
C14—C13—C18121.2 (3)C17—C16—H16120.4
O1—Cu1—O2—Cu1i96.20 (12)C8—N1—C7—C6−66.1 (5)
O1—Cu1—O2—C18−123.4 (2)C7—N1—C11—C10−170.3 (4)
O2—Cu1—O1—C1134.9 (2)C11—N1—C7—C6169.5 (4)
O1—Cu1—O2i—Cu1i−97.27 (11)C8—N1—C11—C1062.6 (5)
O1—Cu1—O2i—C18i31.3 (3)C11—N1—C8—C9−63.2 (4)
O2i—Cu1—O1—C1−138.5 (2)Cu1—N2—C9—C8−44.0 (3)
O1—Cu1—N1—C7−12.9 (3)Cu1—N2—C10—C1143.3 (4)
O1—Cu1—N1—C8111.7 (2)Cu1—N2—C12—C13−53.1 (4)
O1—Cu1—N1—C11−135.2 (2)C9—N2—C10—C11−64.7 (4)
N1—Cu1—O1—C1−33.7 (3)C10—N2—C9—C864.4 (3)
O1—Cu1—N2—C912.7 (5)C9—N2—C12—C1365.1 (4)
O1—Cu1—N2—C10−99.3 (4)C12—N2—C9—C8−169.8 (3)
O1—Cu1—N2—C12136.8 (4)C10—N2—C12—C13−171.8 (4)
N2—Cu1—O1—C17.5 (5)C12—N2—C10—C11169.2 (4)
O2—Cu1—O2i—C18i128.6 (3)O1—C1—C2—Cl1−1.8 (5)
O2i—Cu1—O2—C18140.4 (2)O1—C1—C2—C3−179.4 (3)
O2—Cu1—N1—C7−148.4 (3)O1—C1—C6—C5−179.4 (3)
O2—Cu1—N1—C8−23.8 (5)O1—C1—C6—C75.2 (5)
O2—Cu1—N1—C1189.3 (5)C2—C1—C6—C52.3 (5)
N1—Cu1—O2—Cu1i−128.7 (4)C2—C1—C6—C7−173.1 (3)
N1—Cu1—O2—C1811.7 (5)C6—C1—C2—Cl1176.5 (2)
O2—Cu1—N2—C9−115.2 (2)C6—C1—C2—C3−1.0 (5)
O2—Cu1—N2—C10132.8 (3)Cl1—C2—C3—C4−178.9 (3)
O2—Cu1—N2—C128.9 (3)C1—C2—C3—C4−1.3 (6)
N2—Cu1—O2—Cu1i−97.46 (12)C2—C3—C4—Cl2179.2 (3)
N2—Cu1—O2—C1843.0 (2)C2—C3—C4—C52.5 (6)
O2i—Cu1—N1—C785.0 (3)Cl2—C4—C5—C6−177.9 (3)
O2i—Cu1—N1—C8−150.4 (2)C3—C4—C5—C6−1.3 (6)
O2i—Cu1—N1—C11−37.3 (2)C4—C5—C6—C1−1.2 (6)
N1—Cu1—O2i—Cu1i166.91 (10)C4—C5—C6—C7174.1 (4)
N1—Cu1—O2i—C18i−64.5 (3)C1—C6—C7—N1−55.4 (6)
O2i—Cu1—N2—C9158.6 (2)C5—C6—C7—N1129.1 (4)
O2i—Cu1—N2—C1046.6 (3)N1—C8—C9—N2−0.5 (4)
O2i—Cu1—N2—C12−77.3 (2)N2—C10—C11—N11.5 (6)
N2—Cu1—O2i—Cu1i92.37 (12)N2—C12—C13—C14−120.3 (4)
N2—Cu1—O2i—C18i−139.0 (3)N2—C12—C13—C1856.3 (6)
N1—Cu1—N2—C956.1 (2)C12—C13—C14—C15177.7 (4)
N1—Cu1—N2—C10−56.0 (3)C12—C13—C18—O22.5 (7)
N1—Cu1—N2—C12−179.9 (2)C12—C13—C18—C17−176.0 (4)
N2—Cu1—N1—C7178.8 (3)C14—C13—C18—O2179.0 (4)
N2—Cu1—N1—C8−56.5 (2)C14—C13—C18—C170.5 (7)
N2—Cu1—N1—C1156.5 (2)C18—C13—C14—C151.1 (8)
Cu1—O1—C1—C2−140.0 (3)C13—C14—C15—Cl3−179.6 (4)
Cu1—O1—C1—C641.7 (5)C13—C14—C15—C16−2.2 (8)
Cu1—O2—C18—C13−54.9 (5)Cl3—C15—C16—C17179.0 (4)
Cu1—O2—C18—C17123.5 (4)C14—C15—C16—C171.6 (9)
Cu1i—O2—C18—C1366.2 (6)C15—C16—C17—Cl4−178.5 (4)
Cu1i—O2—C18—C17−115.3 (4)C15—C16—C17—C180.2 (6)
Cu1—N1—C7—C652.4 (5)Cl4—C17—C18—O2−1.0 (7)
Cu1—N1—C8—C945.0 (3)Cl4—C17—C18—C13177.5 (3)
Cu1—N1—C11—C10−45.7 (4)C16—C17—C18—O2−179.7 (5)
C7—N1—C8—C9170.8 (3)C16—C17—C18—C13−1.2 (7)

Symmetry codes: (i) −x+1/2, −y+1/2, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C11—H12···Cl4i0.972.763.544 (5)138
C12—H14···O1i0.972.193.112 (6)159

Symmetry codes: (i) −x+1/2, −y+1/2, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FK2007).

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