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Crystal structure and Hirshfeld surface analysis of trans-2,5-di­methyl­piperazine-1,4-diium tetra­chlorido­cobaltate(II)

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aUniversité de Carthage, Faculté des Sciences de Bizerte, LR13ES08, Laboratoire de Chimie des Matériaux, 7021, Zarzouna Bizerte, Tunisia
*Correspondence e-mail: landolsimeriem@gmail.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 10 March 2021; accepted 19 March 2021; online 26 March 2021)

In the title mol­ecular salt, (C6H16N2)[CoCl4], the complete dication is generated by crystallographic inversion symmetry and the piperazine ring adopts a chair conformation with the pendant methyl groups in equatorial orientations. The complete dianion is generated by crystallographic twofold symmetry. In the crystal, the (C6H16N2)2+ and [CoCl4]2− ions are linked by N—H⋯Cl and C—H⋯Cl hydrogen bonds, thereby forming a two-dimensional supra­molecular network. The Hirshfeld surface analysis and fingerprint plots reveal that the largest contributions to the crystal stability come from H⋯Cl/Cl⋯H (68.4%) and H⋯H (27.4%) contacts.

1. Chemical context

Tetra­chloro­cobalt/copper (II) salts with organic cations, such as (C6H10N3)2[CoCl4] (Titi et al. 2020[Titi, A., Warad, I., Tillard, M., Touzani, R., Messali, M., El Kodadi, M., Eddike, D. & Zarrouk, A. (2020). J. Mol. Struct. 1217, 128422.]), [(CH3)2NH2]2[CoCl4] (Pietraszko et al. 2006[Pietraszko, A., Kirpichnikova, L. F., Sheleg, A. U. & Yachkovsky, A. Ya. (2006). Crystallogr. Rep. 51, 34-36.]) and (C7H7N2S)2[CuCl4] (Vishwakarma et al. 2017[Vishwakarma, A. K., Kumari, R., Ghalsasi, P. S. & Arulsamy, N. (2017). J. Mol. Struct. 1141, 93-98.]) have received attention due to their potential applications in the electronic, magnetic, optical and anti­microbial fields. In these materials, the negative charge on the inorganic complex ion is balanced by the organic groups, which usually act as structure-directing agents by the formation of N—H⋯Cl hydrogen bonds and significantly affect the structure and dimensionality of the supra­molecular network.

[Scheme 1]

As an extension of these studies, we now describe the synthesis, structure and Hirshfeld surface analysis of the title mol­ecular salt, (I)[link].

2. Structural commentary

The asymmetric unit of (I)[link] comprises half of a trans-2,5-di­methyl­piperazine-1,4-dium cation and a half tetra­chlorido­cobaltate anion (Fig. 1[link]). The cation and anion are completed by crystallographic inversion and twofold symmetry, respectively. In the organic species, the N—C and C—C bond lengths vary from 1.490 (2) to 1.513 (2) Å and the angles C—C—C, N—C—C and C—N—C range from 109.15 (14) to 113.54 (15)°. These data are in agreement with those reported in other salts of the trans-2,5-di­methyl­piperazine-1,4-diium cation (Gatfaoui et al., 2014[Gatfaoui, S., Roisnel, T., Dhaouadi, H. & Marouani, H. (2014). Acta Cryst. E70, o725.]; Ben Mleh et al., 2016[Ben Mleh, C., Roisnel, T. & Marouani, H. (2016). Acta Cryst. E72, 593-596.]). The Co2+ ion in (I)[link] has a tetra­hedral geometry, with Cl—Co—Cl angles ranging from 103.32 (2) to 116.57 (3)°. The average length of the Co—Cl bonds, 2.27 Å, is close to that observed in similar complexes (Tahenti et al., 2020[Tahenti, M., Gatfaoui, S., Issaoui, N., Roisnel, T. & Marouani, H. (2020). J. Mol. Struct. 1207, 1-5.]; Zhang et al., 2005[Zhang, H., Fang, L. & Yuan, R. (2005). Acta Cryst. E61, m677-m678.]; Zeller et al., 2005[Zeller, A., Herdtweck, E. & Strassner, T. (2005). Acta Cryst. C61, m46-m47.]).

[Figure 1]
Figure 1
The mol­ecular structure of (I)[link] with displacement ellipsoids set to 50% probability and hydrogen bonds shown as dashed lines. Symmetry codes: (i) −x + 1, y, −z + [{3\over 2}]; (ii) −x + 2, −y + 1, −z + 1.

3. Supra­molecular features

In the crystal of (I)[link], adjacent anions are inter­connected by the cations via N—H⋯Cl hydrogen bonds and C—H⋯Cl inter­actions (Table 1[link]) to form a layer built up from the organic and inorganic species, lying parallel to (101) (Fig. 2[link]). The hydrogen bonds engage the chloride ions of the [CoCl4]2– tetra­hedron, producing four types of graph-set motifs on the basis of Etter's notation (Etter et al., 1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]; Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N. L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). The isolated mol­ecules can be described by the elementary graph-set descriptors Ead (n) (Daszkiewicz, 2012[Daszkiewicz, M. (2012). Struct. Chem. 23, 307-313.]). The graph-set descriptor of the pattern can be easily obtained by the summation of elementary Ead (n) graph-sets of isolated ions and mol­ecules. In the case of (I)[link], the elementary graph-sets can be collected (Fig. 3[link]) as follows:

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯Cl1i 0.89 2.30 3.1777 (2) 171
N1—H1B⋯Cl1 0.89 2.65 3.2594 (2) 126
N1—H1B⋯Cl2 0.89 2.49 3.2631 (2) 145
C1—H1C⋯Cl2ii 0.97 2.82 3.7065 (2) 153
Symmetry codes: (i) [-x+2, y, -z+{\script{3\over 2}}]; (ii) [-x+1, -y+1, -z+1].
[Figure 2]
Figure 2
(a) Crystal packing in the structure of (I)[link] along the crystallographic a axis. (b) View of a supra­molecular layer along the b-axis direction.
[Figure 3]
Figure 3
Hydrogen-bonding inter­actions between cations and anions showing the ring patterns of weak inter­actions formed by N—H⋯Cl/C—H⋯Cl links.

E01 (1) + E20 (3) = R12 (4)

2E02 (3) + 2E10 (1) = R42 (8)

E02 (3) + E20 (5) = R22 (8)

2E10 (1) + 2E02 (4) = R42 (10).

4. Hirshfeld surface analysis

To further understand the different inter­actions and contacts in the crystal of (I)[link], its Hirshfeld surface (HS) (McKinnon et al., 2004[McKinnon, J. J., Spackman, M. A. & Mitchell, A. S. (2004). Acta Cryst. B60, 627-668.]) was calculated. The dnorm surface (Fig. 4[link]) and the associated two-dimensional fingerprint plots (see supporting information) were calculated using CrystalExplorer 3.1 (Wolff et al., 2013[Wolff, S. K., Grimwood, D. J., McKinnon, J. J., Turner, M. J., Jayatilaka, D. & Spackman, M. A. (2013). Crystal Explorer. University of Western Australia.]; Spackman & Jayatilaka, 2009[Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19-32.]). This figure shows the areas mapped in the range from −0.480 to 1.048 of the asymmetric ion-pair surrounded by neighboring ions where we can see some of the closest inter­molecular contacts. The large dark-red spots on the HS indicate close contact inter­actions, which are primarily responsible for significant hydrogen-bond contacts. The fingerprint plots indicate that the most important inter­actions are H⋯Cl/Cl⋯H, which cover a HS range of 68.4% and appear as two shape-symmetric spikes in the two-dimensional fingerprint maps (where dide ∼1.4 Å). It should be also noted that the the van der Waals radii of the hydrogen and chlorine atoms are 1.20 and 1.75 Å, respectively. The H⋯H contacts represent the second most abundant inter­actions with 27.4% of the total Hirshfeld surface, including a short H⋯H contact near 2.4 Å (where dide ∼1.2 Å), represented by a cluster of points accumulated on the diagonal of the graph. Other contacts including Cl⋯Cl and Co⋯H/H⋯Co have negligible contributions (respectively 2.7% and 1.5%). It can be concluded that the Cl⋯H/H⋯Cl inter­actions dominate in the title compound.

[Figure 4]
Figure 4
Hirshfeld surface of (I)[link] mapped over dnorm and the two-dimensional fingerprint plot for all inter­actions.

4.1. Synthesis and crystallization

A 1:1 mixture of trans-2,5-di­methyl­piperazine and cobalt(II) chloride hexa­hydrate was dissolved in a solution of concentrated hydro­chloric acid and the resulting solution was magnetically stirred for 1 h. After two weeks of evaporation, dark-blue prismatic crystals of (I)[link] had formed, which were recovered by filtration and dried in air.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link]. The N-bound and C-bound hydrogen atoms were positioned geometrically and treated as riding atoms: N—H = 0.86 Å, C—H = 0.96 Å with Uiso(H) = 1.2Ueq(N,C).

Table 2
Experimental details

Crystal data
Chemical formula C6H16N22+·Cl4Co2−
Mr 316.94
Crystal system, space group Monoclinic, C2/c
Temperature (K) 293
a, b, c (Å) 7.6431 (3), 11.9347 (6), 14.0058 (7)
β (°) 95.519 (4)
V3) 1271.66 (10)
Z 4
Radiation type Mo Kα
μ (mm−1) 2.15
Crystal size (mm) 0.15 × 0.10 × 0.08
 
Data collection
Diffractometer Agilent SuperNova, Single source at offset, Eos
Absorption correction Multi-scan (CrysAlis PRO; Agilent 2014[Agilent (2014). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.])
Tmin, Tmax 0.816, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections 4627, 1546, 1370
Rint 0.029
(sin θ/λ)max−1) 0.685
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.028, 0.074, 1.08
No. of reflections 1546
No. of parameters 60
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.27, −0.59
Computer programs: CrysAlis PRO (Agilent, 2014[Agilent (2014). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]), SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]), SHELXL2017/1 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and ORTEP-III (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]).

Supporting information


Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL2017/1 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 2006) and ORTEP-III (Burnett & Johnson, 1996).

trans-2,5-Dimethylpiperazine-1,4-diium tetrachloridocobaltate(II) top
Crystal data top
C6H16N22+·Cl4Co2F(000) = 644
Mr = 316.94Dx = 1.655 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
a = 7.6431 (3) ÅCell parameters from 2258 reflections
b = 11.9347 (6) Åθ = 4.1–29.0°
c = 14.0058 (7) ŵ = 2.15 mm1
β = 95.519 (4)°T = 293 K
V = 1271.66 (10) Å3Prism, blue
Z = 40.15 × 0.10 × 0.08 mm
Data collection top
Agilent SuperNova, Single source at offset, Eos
diffractometer
1370 reflections with I > 2σ(I)
Detector resolution: 16.0233 pixels mm-1Rint = 0.029
ω scansθmax = 29.1°, θmin = 3.4°
Absorption correction: multi-scan
(CrysAlisPro; Agilent 2014)
h = 109
Tmin = 0.816, Tmax = 1.000k = 1515
4627 measured reflectionsl = 1813
1546 independent reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.028H-atom parameters constrained
wR(F2) = 0.074 w = 1/[σ2(Fo2) + (0.0365P)2 + 0.515P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.027
1546 reflectionsΔρmax = 0.27 e Å3
60 parametersΔρmin = 0.59 e Å3
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co10.5000000.52995 (3)0.7500000.02694 (13)
Cl10.74705 (6)0.42227 (4)0.77647 (3)0.03237 (14)
Cl20.54849 (7)0.62944 (5)0.61790 (4)0.04332 (16)
N10.9250 (2)0.51194 (13)0.58839 (11)0.0276 (3)
H1A1.0152210.4938690.6305380.033*
H1B0.8338570.5276250.6211210.033*
C10.8798 (2)0.41357 (16)0.52524 (14)0.0290 (4)
H1C0.7742460.4298310.4834400.035*
H1D0.8560920.3493240.5644060.035*
C21.0282 (2)0.38575 (15)0.46508 (13)0.0272 (4)
H21.1309010.3619890.5075610.033*
C30.9775 (3)0.29268 (17)0.39440 (16)0.0404 (5)
H3A0.9473440.2268130.4285970.061*
H3B0.8782280.3158430.3517340.061*
H3C1.0746210.2763530.3580310.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.02007 (18)0.0374 (2)0.0236 (2)0.0000.00304 (14)0.000
Cl10.0239 (2)0.0401 (3)0.0327 (3)0.00345 (18)0.00040 (18)0.00462 (18)
Cl20.0334 (3)0.0564 (3)0.0408 (3)0.0047 (2)0.0073 (2)0.0198 (2)
N10.0252 (7)0.0368 (8)0.0217 (8)0.0012 (6)0.0072 (6)0.0004 (6)
C10.0262 (9)0.0337 (10)0.0279 (10)0.0075 (7)0.0065 (7)0.0013 (7)
C20.0253 (8)0.0307 (9)0.0255 (9)0.0012 (7)0.0023 (7)0.0026 (7)
C30.0450 (11)0.0375 (11)0.0394 (12)0.0026 (9)0.0074 (10)0.0076 (9)
Geometric parameters (Å, º) top
Co1—Cl2i2.2588 (5)C1—C21.513 (2)
Co1—Cl22.2588 (5)C1—H1C0.9700
Co1—Cl12.2846 (5)C1—H1D0.9700
Co1—Cl1i2.2847 (5)C2—C31.513 (3)
N1—C11.490 (2)C2—H20.9800
N1—C2ii1.494 (2)C3—H3A0.9600
N1—H1A0.8900C3—H3B0.9600
N1—H1B0.8900C3—H3C0.9600
Cl2i—Co1—Cl2116.57 (3)N1—C1—H1D109.4
Cl2i—Co1—Cl1111.157 (19)C2—C1—H1D109.4
Cl2—Co1—Cl1103.324 (18)H1C—C1—H1D108.0
Cl2i—Co1—Cl1i103.325 (18)N1ii—C2—C1109.15 (14)
Cl2—Co1—Cl1i111.155 (19)N1ii—C2—C3109.31 (16)
Cl1—Co1—Cl1i111.54 (3)C1—C2—C3111.50 (16)
C1—N1—C2ii113.54 (15)N1ii—C2—H2108.9
C1—N1—H1A108.9C1—C2—H2108.9
C2ii—N1—H1A108.9C3—C2—H2108.9
C1—N1—H1B108.9C2—C3—H3A109.5
C2ii—N1—H1B108.9C2—C3—H3B109.5
H1A—N1—H1B107.7H3A—C3—H3B109.5
N1—C1—C2111.10 (14)C2—C3—H3C109.5
N1—C1—H1C109.4H3A—C3—H3C109.5
C2—C1—H1C109.4H3B—C3—H3C109.5
C2ii—N1—C1—C256.5 (2)N1—C1—C2—C3174.91 (16)
N1—C1—C2—N1ii54.0 (2)
Symmetry codes: (i) x+1, y, z+3/2; (ii) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···Cl1iii0.892.303.1777 (2)171
N1—H1B···Cl10.892.653.2594 (2)126
N1—H1B···Cl20.892.493.2631 (2)145
C1—H1C···Cl2iv0.972.823.7065 (2)153
Symmetry codes: (iii) x+2, y, z+3/2; (iv) x+1, y+1, z+1.
 

Acknowledgements

We would like thank Professor Shu Hua Zhang from Guilin University of Technology for collecting the XRD data.

References

First citationAgilent (2014). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.  Google Scholar
First citationAltomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.  CrossRef Web of Science IUCr Journals Google Scholar
First citationBen Mleh, C., Roisnel, T. & Marouani, H. (2016). Acta Cryst. E72, 593–596.  CSD CrossRef IUCr Journals Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N. L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
First citationBrandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
First citationBurnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.  Google Scholar
First citationDaszkiewicz, M. (2012). Struct. Chem. 23, 307–313.  Web of Science CSD CrossRef CAS Google Scholar
First citationEtter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–262.  CrossRef ICSD CAS Web of Science IUCr Journals Google Scholar
First citationGatfaoui, S., Roisnel, T., Dhaouadi, H. & Marouani, H. (2014). Acta Cryst. E70, o725.  CSD CrossRef IUCr Journals Google Scholar
First citationMcKinnon, J. J., Spackman, M. A. & Mitchell, A. S. (2004). Acta Cryst. B60, 627–668.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationPietraszko, A., Kirpichnikova, L. F., Sheleg, A. U. & Yachkovsky, A. Ya. (2006). Crystallogr. Rep. 51, 34–36.  CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2015). Acta Cryst. C71, 3–8.  Web of Science CrossRef IUCr Journals Google Scholar
First citationSpackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19–32.  Web of Science CrossRef CAS Google Scholar
First citationTahenti, M., Gatfaoui, S., Issaoui, N., Roisnel, T. & Marouani, H. (2020). J. Mol. Struct. 1207, 1–5.  CSD CrossRef Google Scholar
First citationTiti, A., Warad, I., Tillard, M., Touzani, R., Messali, M., El Kodadi, M., Eddike, D. & Zarrouk, A. (2020). J. Mol. Struct. 1217, 128422.  CSD CrossRef Google Scholar
First citationVishwakarma, A. K., Kumari, R., Ghalsasi, P. S. & Arulsamy, N. (2017). J. Mol. Struct. 1141, 93–98.  CSD CrossRef CAS Google Scholar
First citationWolff, S. K., Grimwood, D. J., McKinnon, J. J., Turner, M. J., Jayatilaka, D. & Spackman, M. A. (2013). Crystal Explorer. University of Western Australia.  Google Scholar
First citationZeller, A., Herdtweck, E. & Strassner, T. (2005). Acta Cryst. C61, m46–m47.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationZhang, H., Fang, L. & Yuan, R. (2005). Acta Cryst. E61, m677–m678.  Web of Science CSD CrossRef IUCr Journals Google Scholar

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