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

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ISSN: 2056-9890
Volume 68| Part 4| April 2012| Pages m375-m376

Di­chlorido­tetra­kis­(1H-1,2,4-triazole-κN4)copper(II)

aFaculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, 1000 Ljubljana, Slovenia
*Correspondence e-mail: maja.vidmar@fkkt.uni-lj.si

(Received 22 February 2012; accepted 28 February 2012; online 3 March 2012)

The central CuII atom of the molecular title complex, [CuCl2(C2H3N3)4], is situated on a site with symmetry 2.22. It is six-coordinated in an elongated octa­hedral geometry, with the equatorial plane defined by four N atoms of four 1,2,4-triazole ligands and the axial positions occupied by two Cl atoms situated on a twofold axis. The mol­ecules are connected via N—H⋯Cl hydrogen bonds and the crystal consists of two inter­penetrating three-dimensional hydrogen-bonded frameworks.

Related literature

For the synthesis and structure of copper(II) coordination compounds with 1,2,4-triazole derivatives, see: Zhang et al. (2003[Zhang, P.-Z., Wu, J., Gong, Y.-O., Hu, X.-R. & Gu, J.-M. (2003). Chin. J. Inorg. Chem. 19, 909-912.]); Zhang & Wu (2005[Zhang, P.-Z. & Wu, J. (2005). Acta Cryst. E61, m560-m562.]); Zhao et al. (2009[Zhao, X.-X., Ma, J.-P., Shen, D.-Z., Dong, Y.-B. & Huang, R.-Q. (2009). CrystEngComm, 11, 1281-1290.]); Haasnoot (2000[Haasnoot, J. G. (2000). Coord. Chem. Rev. 200-202, 131-185.]). For the synthesis and structure of 1,2,4-triazole with other metal ions, see: Arion et al. (2003[Arion, V. B., Reisner, E., Fremuth, M., Jakupec, M. A., Keppler, B. K., Kukushkin, V. Y. & Pombeiro, A. J. L. (2003). Inorg. Chem. 42, 6024-6031.]), Haasnoot (2000[Haasnoot, J. G. (2000). Coord. Chem. Rev. 200-202, 131-185.]). For properties of some CuII complexes of pesticides, see: Kamiya & Kameyama (2001[Kamiya, M. & Kameyama, K. (2001). Chemosphere, 45, 231-235.]); Morillo et al. (2002[Morillo, E., Undabeytia, T., Maqueda, C. & Ramos, A. (2002). Chemosphere, 47, 747-752.]).

[Scheme 1]

Experimental

Crystal data
  • [CuCl2(C2H3N3)4]

  • Mr = 410.75

  • Tetragonal, I 41 /a c d

  • a = 14.4471 (3) Å

  • c = 15.8181 (3) Å

  • V = 3301.53 (12) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 1.67 mm−1

  • T = 294 K

  • 0.30 × 0.24 × 0.22 mm

Data collection
  • Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (DENZO-SMN; Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) Tmin = 0.635, Tmax = 0.711

  • 21092 measured reflections

  • 952 independent reflections

  • 776 reflections with I > 2σ(I)

  • Rint = 0.035

Refinement
  • R[F2 > 2σ(F2)] = 0.025

  • wR(F2) = 0.067

  • S = 1.10

  • 952 reflections

  • 59 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.40 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Selected bond lengths (Å)

Cu1—N1 2.0049 (12)
Cu1—Cl1 2.8296 (6)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯Cl1i 0.80 (2) 2.28 (2) 3.0626 (16) 164 (2)
Symmetry code: (i) [x, y+{\script{1\over 2}}, -z].

Data collection: COLLECT (Nonius, 2000[Nonius (2000). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; program(s) used to solve structure: SIR08 (Burla et al., 2007[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G., Siliqi, D. & Spagna, R. (2007). J. Appl. Cryst. 40, 609-613.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

The 1,2,4-triazoles are being widely used as pharmaceutical and as agricultural chemicals (Haasnoot, 2000). There has also been considerable research on complexation of pesticides with metal ions since it influences their pharmacological and toxicological properties (Arion et al., 2003; Zhang et al., 2003; Kamiya & Kameyama, 2001; Morillo et al., 2002). We report here the preparation and structure of the novel CuII complex, (I), containing the 1-H-1,2,4-triazole ligands.

The title compound [CuCl2(C2H3N3)4] is mononuclear complex, where central CuII atom has a distorted (4 + 2) octahedral coordination environment with four N atoms of 1-H-1,2,4-triazole ligands in the equatorial plane and two axial trans positioned chlorido ligands. The Cu—N and Cu—Cl bond distances (Table 1) indicate Jahn-Teller elongation of the coordination octahedron. Similar coordination bond lengths and elongation were observed also in all three known structures of analogous mononuclear CuII complexes containing four coordinated triazolo derivatives and two choride ions at axial position (Zhang & Wu, 2005; Zhang et al., 2003; Zhao et al., 2009). Figure 1 shows the ORTEP drawing of complex molecule of (I). The Cu atom lies on a cross-section of three twofold rotation axes (Wyckoff position b) and both Cl atoms from the molecule lie on one of these twofold axes (Wyckoff position f). Conformation of the molecule is a propeller like. N2 atom is a donor of intermolecular hydrogen bond accepted by Cl atom (symmetry code: x, y + 1/2, -z) from neighbouring molecule. This way molecules are linked into a three-dimensional hydrogen-bonding framework (Figure 2, Table 2). The crystal of (I) consists of two interpenetrating three-dimesional hydrogen-bond frameworks.

Related literature top

For the synthesis and structure of copper(II) coordination compounds with 1,2,4-triazole derivatives, see: Zhang et al. (2003); Zhang & Wu ( 2005); Zhao et al. (2009); Haasnoot (2000). For the synthesis and structure of 1,2,4-triazole with other metal ions, see: Arion et al. (2003), Haasnoot (2000). For properties of some CuII complexes of pesticides, see: Kamiya & Kameyama (2001); Morillo et al. (2002).

Experimental top

To a solution of hydrated copper(II) nitrate(V) (0.196 g, 0.81 mmol) in distilled water (40.0 ml) was added a solution of 37% hydrochloric acid (4.0 ml). The pale blue solution was heated till boiling and the colour changed into green. To a cooled solution was added borax (0.400 g, 1.05 mmol) and 1,2,4-triazole (9.600 g, 0.140 mol). The dark blue solution was obtained and at the end NaCl (7.00 g, 0.120 mol) was added. The solution was left for 48 h and the blue crystals suitable for X-ray analysis were obtained.

Refinement top

H atoms were positioned geometrically and allowed to ride on their parent atoms [C—H = 0.93 Å for aromatic H atoms and Uiso(H) = 1.2 times Ueq(C)] with exception H atom bonded to N atom which was freely refined isotropically.

Structure description top

The 1,2,4-triazoles are being widely used as pharmaceutical and as agricultural chemicals (Haasnoot, 2000). There has also been considerable research on complexation of pesticides with metal ions since it influences their pharmacological and toxicological properties (Arion et al., 2003; Zhang et al., 2003; Kamiya & Kameyama, 2001; Morillo et al., 2002). We report here the preparation and structure of the novel CuII complex, (I), containing the 1-H-1,2,4-triazole ligands.

The title compound [CuCl2(C2H3N3)4] is mononuclear complex, where central CuII atom has a distorted (4 + 2) octahedral coordination environment with four N atoms of 1-H-1,2,4-triazole ligands in the equatorial plane and two axial trans positioned chlorido ligands. The Cu—N and Cu—Cl bond distances (Table 1) indicate Jahn-Teller elongation of the coordination octahedron. Similar coordination bond lengths and elongation were observed also in all three known structures of analogous mononuclear CuII complexes containing four coordinated triazolo derivatives and two choride ions at axial position (Zhang & Wu, 2005; Zhang et al., 2003; Zhao et al., 2009). Figure 1 shows the ORTEP drawing of complex molecule of (I). The Cu atom lies on a cross-section of three twofold rotation axes (Wyckoff position b) and both Cl atoms from the molecule lie on one of these twofold axes (Wyckoff position f). Conformation of the molecule is a propeller like. N2 atom is a donor of intermolecular hydrogen bond accepted by Cl atom (symmetry code: x, y + 1/2, -z) from neighbouring molecule. This way molecules are linked into a three-dimensional hydrogen-bonding framework (Figure 2, Table 2). The crystal of (I) consists of two interpenetrating three-dimesional hydrogen-bond frameworks.

For the synthesis and structure of copper(II) coordination compounds with 1,2,4-triazole derivatives, see: Zhang et al. (2003); Zhang & Wu ( 2005); Zhao et al. (2009); Haasnoot (2000). For the synthesis and structure of 1,2,4-triazole with other metal ions, see: Arion et al. (2003), Haasnoot (2000). For properties of some CuII complexes of pesticides, see: Kamiya & Kameyama (2001); Morillo et al. (2002).

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR08 (Burla et al., 2007); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are drawn as small spheres of arbitrary radii. [Symmetry codes: (i) -x, -y + 1/2, z; (ii) -y + 1/4, -x + 1/4, -z + 1/4; (iii) y - 1/4, x + 1/4, -z + 1/4.]
[Figure 2] Fig. 2. Fragment of a three-dimensional hydrogen-bond framework formed via N—H···Cl intermolecular interactions.
Dichloridotetrakis(1H-1,2,4-triazole-κN4)copper(II) top
Crystal data top
[CuCl2(C2H3N3)4]Dx = 1.653 Mg m3
Mr = 410.75Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I41/acdCell parameters from 1966 reflections
Hall symbol: -I 4bd 2cθ = 2.6–27.5°
a = 14.4471 (3) ŵ = 1.67 mm1
c = 15.8181 (3) ÅT = 294 K
V = 3301.53 (12) Å3Prism, dark blue
Z = 80.30 × 0.24 × 0.22 mm
F(000) = 1656
Data collection top
Nonius KappaCCD
diffractometer
952 independent reflections
Radiation source: fine-focus sealed tube776 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.035
φ and ω scansθmax = 27.5°, θmin = 3.4°
Absorption correction: multi-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
h = 1313
Tmin = 0.635, Tmax = 0.711k = 1818
21092 measured reflectionsl = 2020
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.025 w = 1/[σ2(Fo2) + (0.0335P)2 + 1.7204P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.067(Δ/σ)max < 0.001
S = 1.10Δρmax = 0.40 e Å3
952 reflectionsΔρmin = 0.26 e Å3
59 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0043 (3)
Crystal data top
[CuCl2(C2H3N3)4]Z = 8
Mr = 410.75Mo Kα radiation
Tetragonal, I41/acdµ = 1.67 mm1
a = 14.4471 (3) ÅT = 294 K
c = 15.8181 (3) Å0.30 × 0.24 × 0.22 mm
V = 3301.53 (12) Å3
Data collection top
Nonius KappaCCD
diffractometer
952 independent reflections
Absorption correction: multi-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
776 reflections with I > 2σ(I)
Tmin = 0.635, Tmax = 0.711Rint = 0.035
21092 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0250 restraints
wR(F2) = 0.067H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.40 e Å3
952 reflectionsΔρmin = 0.26 e Å3
59 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Cu10.00000.25000.12500.03175 (17)
Cl10.13849 (3)0.11151 (3)0.12500.0453 (2)
N10.07460 (8)0.31410 (8)0.03559 (8)0.0329 (3)
N30.16037 (11)0.33828 (11)0.07999 (9)0.0488 (4)
N20.13429 (10)0.41905 (11)0.04391 (10)0.0436 (4)
C20.12290 (12)0.27712 (13)0.02974 (10)0.0435 (4)
H2A0.12880.21370.03800.052*
C30.08400 (11)0.40417 (11)0.02389 (10)0.0386 (4)
H30.05890.44990.05830.046*
H20.1460 (16)0.4665 (16)0.0679 (13)0.059 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.03525 (19)0.03525 (19)0.0247 (2)0.01284 (14)0.0000.000
Cl10.0398 (2)0.0398 (2)0.0562 (4)0.0036 (2)0.01066 (18)0.01066 (18)
N10.0358 (7)0.0325 (6)0.0305 (6)0.0064 (5)0.0031 (5)0.0016 (5)
N30.0550 (9)0.0519 (9)0.0395 (8)0.0014 (7)0.0144 (7)0.0045 (7)
N20.0465 (8)0.0386 (8)0.0457 (8)0.0059 (6)0.0072 (7)0.0109 (7)
C20.0573 (11)0.0370 (8)0.0362 (8)0.0013 (8)0.0102 (8)0.0021 (7)
C30.0410 (9)0.0337 (8)0.0411 (9)0.0021 (7)0.0060 (7)0.0019 (7)
Geometric parameters (Å, º) top
Cu1—N12.0049 (12)N3—N21.353 (2)
Cu1—Cl12.8296 (6)N2—C31.313 (2)
N1—C31.321 (2)N2—H20.80 (2)
N1—C21.357 (2)C2—H2A0.9300
N3—C21.306 (2)C3—H30.9300
N1i—Cu1—N1ii173.87 (7)Cl1i—Cu1—Cl1180.0
N1i—Cu1—N190.27 (7)C3—N1—C2103.20 (13)
N1ii—Cu1—N190.06 (7)C3—N1—Cu1127.51 (10)
N1i—Cu1—N1iii90.06 (7)C2—N1—Cu1129.20 (11)
N1ii—Cu1—N1iii90.27 (7)C2—N3—N2102.21 (13)
N1—Cu1—N1iii173.87 (7)C3—N2—N3110.94 (14)
N1i—Cu1—Cl1i86.93 (3)C3—N2—H2130.1 (16)
N1ii—Cu1—Cl1i86.93 (3)N3—N2—H2118.6 (15)
N1—Cu1—Cl1i93.07 (3)N3—C2—N1114.23 (15)
N1iii—Cu1—Cl1i93.07 (3)N3—C2—H2A122.9
N1i—Cu1—Cl193.07 (3)N1—C2—H2A122.9
N1ii—Cu1—Cl193.07 (3)N2—C3—N1109.42 (14)
N1—Cu1—Cl186.93 (3)N2—C3—H3125.3
N1iii—Cu1—Cl186.93 (3)N1—C3—H3125.3
N1i—Cu1—N1—C3120.99 (15)C2—N3—N2—C30.10 (19)
N1ii—Cu1—N1—C352.88 (12)N2—N3—C2—N10.2 (2)
Cl1i—Cu1—N1—C334.05 (13)C3—N1—C2—N30.22 (19)
Cl1—Cu1—N1—C3145.95 (13)Cu1—N1—C2—N3176.42 (12)
N1i—Cu1—N1—C254.89 (12)N3—N2—C3—N10.0 (2)
N1ii—Cu1—N1—C2131.24 (15)C2—N1—C3—N20.14 (18)
Cl1i—Cu1—N1—C2141.83 (13)Cu1—N1—C3—N2176.58 (11)
Cl1—Cu1—N1—C238.17 (13)
Symmetry codes: (i) x, y+1/2, z; (ii) y1/4, x+1/4, z+1/4; (iii) y+1/4, x+1/4, z+1/4.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···Cl1iv0.80 (2)2.28 (2)3.0626 (16)164 (2)
Symmetry code: (iv) x, y+1/2, z.

Experimental details

Crystal data
Chemical formula[CuCl2(C2H3N3)4]
Mr410.75
Crystal system, space groupTetragonal, I41/acd
Temperature (K)294
a, c (Å)14.4471 (3), 15.8181 (3)
V3)3301.53 (12)
Z8
Radiation typeMo Kα
µ (mm1)1.67
Crystal size (mm)0.30 × 0.24 × 0.22
Data collection
DiffractometerNonius KappaCCD
Absorption correctionMulti-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
Tmin, Tmax0.635, 0.711
No. of measured, independent and
observed [I > 2σ(I)] reflections
21092, 952, 776
Rint0.035
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.025, 0.067, 1.10
No. of reflections952
No. of parameters59
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.40, 0.26

Computer programs: COLLECT (Nonius, 2000), DENZO-SMN (Otwinowski & Minor, 1997), SIR08 (Burla et al., 2007), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008), WinGX (Farrugia, 1999).

Selected bond lengths (Å) top
Cu1—N12.0049 (12)Cu1—Cl12.8296 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···Cl1i0.80 (2)2.28 (2)3.0626 (16)164 (2)
Symmetry code: (i) x, y+1/2, z.
 

Acknowledgements

This work was supported by the Ministry of Education, Science, Culture and Sport of the Republic of Slovenia (grants P1–0175 and MR-33158).

References

First citationArion, V. B., Reisner, E., Fremuth, M., Jakupec, M. A., Keppler, B. K., Kukushkin, V. Y. & Pombeiro, A. J. L. (2003). Inorg. Chem. 42, 6024–6031.  Web of Science CSD CrossRef PubMed CAS Google Scholar
First citationBurla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G., Siliqi, D. & Spagna, R. (2007). J. Appl. Cryst. 40, 609–613.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
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First citationHaasnoot, J. G. (2000). Coord. Chem. Rev. 200–202, 131–185.  Web of Science CrossRef CAS Google Scholar
First citationKamiya, M. & Kameyama, K. (2001). Chemosphere, 45, 231–235.  Web of Science CrossRef PubMed CAS Google Scholar
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First citationNonius (2000). COLLECT. Nonius BV, Delft, The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
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First citationZhang, P.-Z. & Wu, J. (2005). Acta Cryst. E61, m560–m562.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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First citationZhao, X.-X., Ma, J.-P., Shen, D.-Z., Dong, Y.-B. & Huang, R.-Q. (2009). CrystEngComm, 11, 1281–1290.  Web of Science CSD CrossRef CAS Google Scholar

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Volume 68| Part 4| April 2012| Pages m375-m376
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