metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890
Volume 69| Part 11| November 2013| Pages m610-m611

Bis[4-(di­methyl­amino)­pyridinium] tetra­chlorido­cuprate(II)

aUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, CHEMS, Faculté des Sciences Exactes, Université Constantine 1 25000, Constantine, Algeria, and bDépartement Sciences de la Matière, Faculté des Sciences Exactes et Sciences de la Nature et de la Vie, Université Oum El Bouaghi, Algeria
*Correspondence e-mail: bouacida_sofiane@yahoo.fr

(Received 8 October 2013; accepted 11 October 2013; online 19 October 2013)

The asymmetric unit of the title salt, (C7H11N2)2[CuCl4], comprises half a tetrahedral tetra­chlorido­cuprate anion, being located on a twofold axis, and a protonated 4-(di­methyl­amino)­pyridine cation. The geometry around the CuII ion is highly distorted with the range of Cl—Cu—Cl angles being 94.94 (1)–141.03 (1)°. The crystal structure is stabilized by N—H⋯Cl and C—H⋯Cl hydrogen bonds. In the three-dimensional network, cations and anions pack in the lattice so as to generate chains of [CuCl4]2− anions separated by two orientations of cation layers, which are inter­locked through ππ stacking contacts between pairs of pyridine rings, with centroid–centroid distances of 3.7874 (7) Å.

Related literature

For general background to organic-inorganic systems, see: Bouacida (2008[Bouacida, S. (2008). PhD thesis, Montouri-Constantine University, Algeria.]). For related 4-di­methyl­amino­pyridinium metal(II) chloride salts, see: Khadri et al. (2013[Khadri, A., Bouchene, R., Bouacida, S., Merazig, H. & Roisnel, T. (2013). Acta Cryst. E69, m190.]). For the geometry of four-coordinated tetra­halocuprate(II) ions, see: Awwadi et al. (2007[Awwadi, F. F., Willett, R. D. & Twamly, B. (2007). Cryst. Growth Des. 7, 624-632.]); Choi et al. (2002[Choi, S.-N., Lee, Y.-M., Lee, H.-W., Kang, S. K. & Kim, Y.-I. (2002). Acta Cryst. E58, m583-m585.]); Diaz et al. (1999[Diaz, I., Fernandes, V., Belsky, V. K. & Martinez, J. L. (1999). Z. Naturforsch. Teil B, 54, 718-724.]); Haddad et al. (2006[Haddad, S. F., Aidamen, M. A. & Willett, R. D. (2006). Inorg. Chim. Acta, 359, 424-432.]); Harlow et al. (1975[Harlow, R. L., Wells, W. J., Watt, G. W. & Simonsen, S. H. (1975). Inorg. Chem. 14, 1786-1772.]); Marzotto et al. (2001[Marzotto, A., Clemente, D. A., Benetollo, F. & Valle, G. (2001). Polyhedron, 20, 171-177.]); Parent et al. (2007[Parent, A. R., Landee, C. P. & Turnbull, M. M. (2007). Inorg. Chim. Acta, 360, 1943-1953.]).

[Scheme 1]

Experimental

Crystal data
  • (C7H11N2)2[CuCl4]

  • Mr = 451.71

  • Monoclinic, C 2/c

  • a = 12.3750 (8) Å

  • b = 12.1901 (8) Å

  • c = 14.1713 (9) Å

  • β = 115.023 (1)°

  • V = 1937.1 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.68 mm−1

  • T = 150 K

  • 0.13 × 0.12 × 0.10 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2002[Sheldrick, G. M. (2002). SADABS. University of Göttingen, Germany.]) Tmin = 0.675, Tmax = 0.747

  • 12787 measured reflections

  • 3895 independent reflections

  • 3389 reflections with I > 2σ(I)

  • Rint = 0.017

Refinement
  • R[F2 > 2σ(F2)] = 0.021

  • wR(F2) = 0.059

  • S = 1.05

  • 3895 reflections

  • 107 parameters

  • H-atom parameters constrained

  • Δρmax = 0.55 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—Cl1 2.2487 (3)
Cu1—Cl2 2.2588 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯Cl1 0.86 2.55 3.2264 (11) 136
N2—H2⋯Cl2 0.86 2.55 3.2760 (10) 143
C2—H2A⋯Cl1i 0.93 2.67 3.5790 (11) 167
C5—H5⋯Cl2ii 0.93 2.80 3.6501 (11) 152
C11—H11B⋯Cl2iii 0.96 2.82 3.6850 (13) 150
Symmetry codes: (i) [x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]; (ii) [x, -y, z-{\script{1\over 2}}]; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2011[Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SIR2002 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg & Berndt, 2001[Brandenburg, K. & Berndt, M. (2001). DIAMOND. Crystal Impact, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

The role of weak intermolecular interactions in the stabilization of hybrid organic-inorganic systems is one of the main targets of our investigation in crystal engineering study (Bouacida, 2008). In continuation of our recent research on 4-dimethylaminopyridinium (HDMAP) metal halide salts (Khadri et al., 2013), the X-ray crystal structures of new one with tetrachlorocuprate (II) anion is reported.

Electronic subshell d9 of Cu(II) is responsible for distortions of symmetry of the coordination polyhedron. This deals with the Jahn-Teller effect. The shape of the four-coordinated tetrahalocuprate (II) ions changes from square planar (Harlow et al., 1975) to distorted tetrahedral (Diaz et al., 1999) and the geometry of [CuX4]2- species is influenced by the crystal-packing forces resulted from the size and the form of counter cations (Diaz et al., 1999; Parent et al., 2007), hydrogen bonding to cations (Haddad et al., 2006; Marzotto et al., 2001; Choi et al., 2002), and halide-halide interactions in solid (Awwadi et al., 2007). The degree of distortion of [CuX4]2- coordination polyhedra is determined by the mean value of the flattering or trans-angle θ. The asymmetric unit of the title compound, shown in figure 1, contains one half of the copper chloride salt, the other half is generated by a twofold rotation axis (4 e) on which Cu(II) is situated. The [CuCl4]2- ions are highly distorted with a mean trans angle of 141.02° as a result of hydrogen bonding interactions with two nearly planar HDMAP cations (0.0295 Å mean deviation). The pyridinium nitrogen forms bifurcated hydrogen bond to two chloride ligands Cl1 and Cl2 and the created organic-inorganic hybrid compound (Fig. 2) is further assembled by C—H···Cl hydrogen bonding interactions (Table 2). In the three dimension network (Fig. 3), cations and anions pack in the lattice to generate chains of [CuX4]2- anions separated by two orientations of cation layers which are interlocked through π-π stacking contacts between pairs of pyridine rings with distances centroid-centroid of 3.7874 (7) Å. All these interactions bonds link the layers together, forming a three-dimensional network and reinforcing the cohesion of ionic structure. Additionel hydrogen bond parameters are listed in table 1.

Related literature top

For general background to organic-inorganic systems, see: Bouacida (2008). For related 4-dimethylaminopyridinium metal(II) chloride salts, see: Khadri et al. (2013). For the geometry of four-coordinated tetrahalocuprate(II) ions, see: Awwadi et al. (2007); Choi et al. (2002); Diaz et al. (1999); Haddad et al. (2006); Harlow et al. (1975); Marzotto et al. (2001); Parent et al. (2007).

Experimental top

4-dimethylaminopyridine and CuCl2·2H2O in a molar ratio of 1:1 were dissolved in sufficient acidified water (HCl, 37%). Evaporation of obtained solution at room temperature yields yellow crystals of the title compound after one week which crystals suitable for X-ray diffraction were carefully isolated.

Refinement top

All H atoms were localized on Fourier maps but introduced in calculated positions and treated as riding on their parent atoms (C and N) with C—H = 0.96 Å (methyl) or C—H = 0.93 Å (aromatic) N—H = 0.86 Å and with Uiso(H) = 1.2 Ueq(Caryl or N )and Uiso(H) = 1.5 Ueq(Cmethyl).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SIR2002 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg & Berndt, 2001); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. A view of molecule structure of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. (Brandenburg & Berndt, 2001) Partial packing viewed via b axis showing structure as alternating layers of CuCl4 tetrahedral and protonated 4-Dimethylaminopyridine along the c axis and Hydrogen bonds interactions [N—H···Cl and C—H···Cl], as dashed lines.
[Figure 3] Fig. 3. (Brandenburg & Berndt, 2001) Partial packing of (I) showing π-π stacking interactions as red dashed lines.
Bis[4-(dimethylamino)pyridinium] tetrachloridocuprate(II) top
Crystal data top
(C7H11N2)2[CuCl4]F(000) = 924
Mr = 451.71Dx = 1.549 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 6282 reflections
a = 12.3750 (8) Åθ = 2.5–34.7°
b = 12.1901 (8) ŵ = 1.68 mm1
c = 14.1713 (9) ÅT = 150 K
β = 115.023 (1)°Cube, yellow
V = 1937.1 (2) Å30.13 × 0.12 × 0.10 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
3895 independent reflections
Radiation source: sealed tube3389 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
ϕ and ω scansθmax = 34.7°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)
h = 1919
Tmin = 0.675, Tmax = 0.747k = 1818
12787 measured reflectionsl = 2222
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.021Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.059H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0283P)2 + 0.9756P]
where P = (Fo2 + 2Fc2)/3
3895 reflections(Δ/σ)max = 0.001
107 parametersΔρmax = 0.55 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
(C7H11N2)2[CuCl4]V = 1937.1 (2) Å3
Mr = 451.71Z = 4
Monoclinic, C2/cMo Kα radiation
a = 12.3750 (8) ŵ = 1.68 mm1
b = 12.1901 (8) ÅT = 150 K
c = 14.1713 (9) Å0.13 × 0.12 × 0.10 mm
β = 115.023 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
3895 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)
3389 reflections with I > 2σ(I)
Tmin = 0.675, Tmax = 0.747Rint = 0.017
12787 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0210 restraints
wR(F2) = 0.059H-atom parameters constrained
S = 1.05Δρmax = 0.55 e Å3
3895 reflectionsΔρmin = 0.22 e Å3
107 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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) top
xyzUiso*/Ueq
N10.43961 (8)0.14134 (8)0.05308 (7)0.0225 (2)
N20.24689 (8)0.09752 (8)0.12016 (7)0.0250 (3)
C10.37610 (8)0.12756 (8)0.00275 (7)0.0179 (2)
C20.39370 (8)0.19580 (8)0.08966 (7)0.0202 (2)
C30.32794 (9)0.17919 (9)0.14518 (8)0.0229 (3)
C40.22731 (9)0.03122 (9)0.03815 (9)0.0259 (3)
C50.28831 (9)0.04393 (8)0.02169 (8)0.0222 (2)
C110.53277 (10)0.22510 (10)0.02403 (9)0.0286 (3)
C120.41514 (11)0.07546 (10)0.14600 (9)0.0280 (3)
Cu10.000000.05740 (1)0.250000.0173 (1)
Cl10.07732 (2)0.06512 (2)0.17693 (2)0.0251 (1)
Cl20.15211 (2)0.17785 (2)0.29261 (2)0.0211 (1)
H20.207300.087600.156800.0300*
H2A0.450100.251700.108600.0240*
H30.339200.224900.201100.0270*
H40.170900.024400.022200.0310*
H50.272600.002000.078400.0270*
H11A0.497600.296400.029700.0430*
H11B0.571800.220700.069800.0430*
H11C0.590000.213100.046400.0430*
H12A0.425200.000800.127500.0420*
H12B0.469400.095700.175400.0420*
H12C0.334700.088200.196200.0420*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0217 (4)0.0262 (4)0.0203 (4)0.0016 (3)0.0097 (3)0.0010 (3)
N20.0215 (4)0.0318 (5)0.0241 (4)0.0019 (3)0.0120 (3)0.0016 (3)
C10.0164 (4)0.0182 (4)0.0172 (4)0.0003 (3)0.0052 (3)0.0015 (3)
C20.0200 (4)0.0194 (4)0.0192 (4)0.0025 (3)0.0063 (3)0.0007 (3)
C30.0226 (4)0.0250 (5)0.0200 (4)0.0010 (3)0.0079 (3)0.0012 (3)
C40.0217 (4)0.0265 (5)0.0276 (5)0.0067 (4)0.0087 (4)0.0001 (4)
C50.0210 (4)0.0215 (4)0.0217 (4)0.0036 (3)0.0067 (3)0.0032 (3)
C110.0245 (5)0.0341 (6)0.0282 (5)0.0058 (4)0.0122 (4)0.0049 (4)
C120.0320 (5)0.0322 (6)0.0216 (4)0.0056 (4)0.0132 (4)0.0010 (4)
Cu10.0164 (1)0.0169 (1)0.0192 (1)0.00000.0082 (1)0.0000
Cl10.0269 (1)0.0203 (1)0.0353 (1)0.0061 (1)0.0200 (1)0.0087 (1)
Cl20.0205 (1)0.0197 (1)0.0232 (1)0.0035 (1)0.0095 (1)0.0029 (1)
Geometric parameters (Å, º) top
Cu1—Cl1i2.2487 (3)C2—C31.3653 (16)
Cu1—Cl2i2.2588 (3)C4—C51.3618 (17)
Cu1—Cl12.2487 (3)C2—H2A0.9300
Cu1—Cl22.2588 (3)C3—H30.9300
N1—C11.3409 (15)C4—H40.9300
N1—C121.4606 (15)C5—H50.9300
N1—C111.4627 (16)C11—H11A0.9600
N2—C31.3498 (15)C11—H11B0.9600
N2—C41.3507 (15)C11—H11C0.9600
N2—H20.8600C12—H12B0.9600
C1—C21.4246 (13)C12—H12C0.9600
C1—C51.4217 (15)C12—H12A0.9600
Cl1i—Cu1—Cl2i94.94 (1)C3—C2—H2A120.00
Cl1—Cu1—Cl2i141.03 (1)C2—C3—H3119.00
Cl1—Cu1—Cl294.94 (1)N2—C3—H3120.00
Cl1—Cu1—Cl1i96.76 (1)N2—C4—H4119.00
Cl1i—Cu1—Cl2141.03 (1)C5—C4—H4119.00
Cl2—Cu1—Cl2i98.91 (1)C1—C5—H5120.00
C1—N1—C12120.89 (10)C4—C5—H5120.00
C1—N1—C11120.68 (9)H11A—C11—H11B109.00
C11—N1—C12118.41 (10)H11A—C11—H11C110.00
C3—N2—C4120.68 (10)N1—C11—H11A109.00
C4—N2—H2120.00N1—C11—H11B109.00
C3—N2—H2120.00N1—C11—H11C109.00
C2—C1—C5116.81 (9)H11B—C11—H11C109.00
N1—C1—C2121.57 (9)H12B—C12—H12C109.00
N1—C1—C5121.62 (9)N1—C12—H12A109.00
C1—C2—C3120.08 (9)N1—C12—H12B109.00
N2—C3—C2121.05 (10)N1—C12—H12C109.00
N2—C4—C5121.52 (11)H12A—C12—H12B109.00
C1—C5—C4119.84 (9)H12A—C12—H12C109.00
C1—C2—H2A120.00
C11—N1—C1—C22.21 (15)N1—C1—C2—C3179.66 (10)
C11—N1—C1—C5177.56 (10)C5—C1—C2—C30.11 (14)
C12—N1—C1—C2175.95 (10)N1—C1—C5—C4178.72 (10)
C12—N1—C1—C54.28 (16)C2—C1—C5—C41.06 (15)
C4—N2—C3—C21.18 (16)C1—C2—C3—N21.00 (16)
C3—N2—C4—C50.20 (17)N2—C4—C5—C10.93 (17)
Symmetry code: (i) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···Cl10.862.553.2264 (11)136
N2—H2···Cl20.862.553.2760 (10)143
C2—H2A···Cl1ii0.932.673.5790 (11)167
C5—H5···Cl2iii0.932.803.6501 (11)152
C11—H11B···Cl2iv0.962.823.6850 (13)150
Symmetry codes: (ii) x+1/2, y+1/2, z; (iii) x, y, z1/2; (iv) x+1/2, y+1/2, z1/2.
Selected bond lengths (Å) top
Cu1—Cl1i2.2487 (3)Cu1—Cl12.2487 (3)
Cu1—Cl2i2.2588 (3)Cu1—Cl22.2588 (3)
Symmetry code: (i) x, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···Cl10.86002.55003.2264 (11)136.00
N2—H2···Cl20.86002.55003.2760 (10)143.00
C2—H2A···Cl1ii0.93002.67003.5790 (11)167.00
C5—H5···Cl2iii0.93002.80003.6501 (11)152.00
C11—H11B···Cl2iv0.96002.82003.6850 (13)150.00
Symmetry codes: (ii) x+1/2, y+1/2, z; (iii) x, y, z1/2; (iv) x+1/2, y+1/2, z1/2.
 

Acknowledgements

We are grateful to all personel of the LCATM laboratory, Université Oum El Bouaghi, Algeria, for their assistance. Thanks are due to the MESRS (Ministére de l'Enseignement Supérieur et de la Recherche Scientifique - Algérie) via the PNR programme for financial support.

References

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ISSN: 2056-9890
Volume 69| Part 11| November 2013| Pages m610-m611
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