supporting information

Acta Cryst. (2013). E69, m410    [ doi:10.1107/S1600536813016747 ]


P. S. Kannan, A. S. Ganeshraja, K. Rajkumar, K. Anbalagan and A. SubbiahPandi

Abstract top

The whole mol­ecule of the title compound, [NiCl2(C3H4N2)2(NH3)2], is generated by inversion symmetry. The NiII ion, which is located on an inversion center, has a distorted octa­hedral coordination environment and is surrounded by two ammine N atoms and two Cl atoms in the equatorial plane, with two N atoms of two imidazole groups occupying the axial positions. The imidazole ring makes a dihedral angle of 81.78 (18)° with the Ni/N/Cl equatorial plane. In the crystal, mol­ecules are linked via N-H...Cl hydrogen bonds and C-H...[pi] inter­actions, forming a three-dimensional network.

Comment top

Knowledge of the detailed coordination behaviour of imidazoles and their limitation in the possible use in complexes with specific catalytic activity is of great current importance. Because of their multiple coordination modes imidazole, namely 1,3-diazacyclopenta- 2,4-diene, and its derivatives have found a wide range of applications in coordination chemistry and for the construction of novel metal–organic frameworks (Huang et al., 2008; Huang et al., 2011).

The chemistry of imidazole occupies an extremely important position within the family of five-membered heterocyclic compounds. Synthesis of imidazole derivatives has attracted great interest in recent years due to their broad spectrum of biological activities (Gaonkar et al., 2009). Herein we report on the crystal structure of the title compound.

The molecular structure of the title compound as illustrated in Fig. 1. The nickel(II) ion is located on an inversion center and has a distorted NiN4Cl2 octahedral coordination environment. It is surrounded by four N atoms, two of which are in the equatorial plane with the Cl atoms, and the remaining two N atoms occupy the axial positions. The imidazole ring (N3/N5/C4/C6/C7) is planar with a maximum deviation of -0.005 (1)Å for atom C4. It makes a dihedral angle of 81.78 (18) ° with the equatorial plane of atoms Ni/Cl2/N3/Cl2a/N3a [symmetry code: (a) -x, -y, -z+1].

In the crystal, molecules are linked via N-H···Cl hydrogen bonds and C-H···π interactions forming a three-dimensional network (Table 1 and Fig. 2).

Related literature top

For applications of imidazole and its derivatives, see: Huang et al. (2008, 2011). For the biological activity of imidazole derivatives, see: Gaonkar et al. (2009).

Experimental top

A total of 10 mL of a 0.01 M aqueous solution of NiCl2 was slowly mixed with 20 mL of a 0.02 M ammonia solution. After 1 h, 20 mL of a 0.02 M aqueous solution of imidazole was added drop wise. The mixture was slowly evaporated at room temperature, and deep-green block-like crystals of the title complex were obtained within 5 days. The crystals were filtered, washed with water, and dried in a desiccator over P4O10.

Refinement top

All the H atoms were fixed geometrically and allowed to ride on their parent N or C atoms: N-H = 0.86 and 0.89 Å for NH and NH3 H atoms, respectively, C—H = 0.93–0.97 Å; Uiso(H) = 1.5Ueq(C-methyl) and = 1.2Ueq(N,C) for other H atoms.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the c axis. Dashed lines show the N—H···Cl hydrogen bonds [see Table 1 for details]
trans-Diamminedichloridobis(1H-imidazole-κN3)nickel(II) top
Crystal data top
[NiCl2(C3H4N2)2(NH3)2]F(000) = 616
Mr = 299.82Dx = 1.758 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 1338 reflections
a = 9.1349 (9) Åθ = 5.2–29.1°
b = 7.9451 (5) ŵ = 2.16 mm1
c = 15.6121 (13) ÅT = 293 K
V = 1133.09 (16) Å3Block, green
Z = 40.5 × 0.4 × 0.4 mm
Data collection top
Oxford Diffraction Xcalibur Eos
1338 independent reflections
Radiation source: fine-focus sealed tube1137 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
Detector resolution: 15.9821 pixels mm-1θmax = 29.1°, θmin = 5.2°
ω and ϕ scanh = 812
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
k = 1010
Tmin = 0.369, Tmax = 0.421l = 2115
4464 measured reflections
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.129H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0565P)2 + 3.9561P]
where P = (Fo2 + 2Fc2)/3
1338 reflections(Δ/σ)max < 0.001
71 parametersΔρmax = 0.76 e Å3
0 restraintsΔρmin = 1.00 e Å3
Crystal data top
[NiCl2(C3H4N2)2(NH3)2]V = 1133.09 (16) Å3
Mr = 299.82Z = 4
Orthorhombic, PbcaMo Kα radiation
a = 9.1349 (9) ŵ = 2.16 mm1
b = 7.9451 (5) ÅT = 293 K
c = 15.6121 (13) Å0.5 × 0.4 × 0.4 mm
Data collection top
Oxford Diffraction Xcalibur Eos
1338 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
1137 reflections with I > 2σ(I)
Tmin = 0.369, Tmax = 0.421Rint = 0.017
4464 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.129H-atom parameters constrained
S = 1.11Δρmax = 0.76 e Å3
1338 reflectionsΔρmin = 1.00 e Å3
71 parameters
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.

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 > 2sigma(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
C40.1725 (5)0.0044 (5)0.3343 (3)0.0331 (9)
C60.0749 (5)0.1968 (6)0.2518 (3)0.0369 (9)
C70.0103 (4)0.1991 (5)0.3298 (2)0.0288 (8)
Cl20.25211 (9)0.00290 (10)0.44598 (5)0.0227 (2)
N30.0715 (3)0.0774 (4)0.38102 (17)0.0209 (6)
N50.1766 (4)0.0725 (5)0.2555 (2)0.0372 (8)
N80.0253 (3)0.2503 (3)0.53954 (16)0.0128 (5)
Ni10.00000.00000.50000.0150 (2)
Atomic displacement parameters (Å2) top
C40.031 (2)0.041 (2)0.0275 (19)0.0049 (16)0.0083 (16)0.0018 (15)
C60.040 (2)0.050 (2)0.0203 (16)0.0078 (19)0.0006 (16)0.0116 (18)
C70.0277 (19)0.035 (2)0.0233 (17)0.0025 (15)0.0011 (14)0.0094 (15)
Cl20.0183 (4)0.0255 (4)0.0242 (4)0.0017 (3)0.0041 (3)0.0038 (3)
N30.0209 (14)0.0267 (14)0.0152 (12)0.0010 (11)0.0022 (11)0.0021 (11)
N50.0391 (19)0.052 (2)0.0206 (14)0.0066 (17)0.0140 (14)0.0034 (15)
N80.0144 (11)0.0118 (10)0.0123 (10)0.0009 (9)0.0010 (9)0.0004 (9)
Ni10.0151 (3)0.0177 (3)0.0123 (3)0.00026 (19)0.00016 (19)0.00066 (19)
Geometric parameters (Å, º) top
C4—N31.312 (5)N3—Ni12.063 (3)
C4—N51.345 (5)N5—H50.8600
C4—H40.9300N8—Ni12.095 (2)
C6—C71.353 (6)N8—H8A0.8900
C6—N51.357 (6)N8—H8B0.8900
C7—N31.374 (5)Ni1—N3i2.063 (3)
C7—H70.9300Ni1—N8i2.095 (2)
Cl2—Ni12.4527 (9)Ni1—Cl2i2.4527 (9)
N3—C4—N5110.5 (4)Ni1—N8—H8C109.5
C7—C6—N5105.7 (3)N3i—Ni1—N3180.0
C7—C6—H6127.1N3i—Ni1—N889.00 (11)
N5—C6—H6127.1N3—Ni1—N891.00 (11)
C6—C7—N3109.7 (4)N3i—Ni1—N8i91.00 (11)
C6—C7—H7125.2N3—Ni1—N8i89.00 (11)
C4—N3—C7105.9 (3)N3i—Ni1—Cl2i89.45 (8)
C4—N3—Ni1126.3 (3)N3—Ni1—Cl2i90.55 (8)
C7—N3—Ni1127.2 (2)N8—Ni1—Cl2i89.62 (7)
C4—N5—C6108.2 (3)N8i—Ni1—Cl2i90.38 (7)
C4—N5—H5125.9N3i—Ni1—Cl290.55 (8)
C6—N5—H5125.9N3—Ni1—Cl289.45 (8)
Ni1—N8—H8A109.5N8—Ni1—Cl290.38 (7)
Ni1—N8—H8B109.5N8i—Ni1—Cl289.62 (7)
N5—C6—C7—N30.1 (5)C4—N3—Ni1—N8143.9 (3)
N5—C4—N3—C70.9 (5)C7—N3—Ni1—N846.1 (3)
N5—C4—N3—Ni1170.8 (3)C4—N3—Ni1—N8i36.1 (3)
C6—C7—N3—C40.6 (5)C7—N3—Ni1—N8i133.9 (3)
C6—C7—N3—Ni1171.1 (3)C4—N3—Ni1—Cl2i54.3 (3)
N3—C4—N5—C60.9 (5)C7—N3—Ni1—Cl2i135.7 (3)
C7—C6—N5—C40.5 (5)C4—N3—Ni1—Cl2125.7 (3)
C4—N3—Ni1—N3i126 (8)C7—N3—Ni1—Cl244.3 (3)
C7—N3—Ni1—N3i64 (8)
Symmetry code: (i) x, y, z+1.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the N3/C4/N5/C6/C7 ring.
N5—H5···Cl2ii0.862.533.268 (3)144
N8—H8A···Cl2iii0.892.323.180 (3)162
N8—H8B···Cl2iv0.892.373.210 (3)157
C4—H4···Cg1v0.932.953.772 (5)148
Symmetry codes: (ii) x+1/2, y, z+1/2; (iii) x1/2, y+1/2, z; (iv) x+1/2, y+1/2, z+1; (v) x1/2, y3/2, z.

Experimental details

Crystal data
Chemical formula[NiCl2(C3H4N2)2(NH3)2]
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)9.1349 (9), 7.9451 (5), 15.6121 (13)
V3)1133.09 (16)
Radiation typeMo Kα
µ (mm1)2.16
Crystal size (mm)0.5 × 0.4 × 0.4
Data collection
DiffractometerOxford Diffraction Xcalibur Eos
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.369, 0.421
No. of measured, independent and
observed [I > 2σ(I)] reflections
4464, 1338, 1137
(sin θ/λ)max1)0.684
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.129, 1.11
No. of reflections1338
No. of parameters71
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.76, 1.00

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the N3/C4/N5/C6/C7 ring.
N5—H5···Cl2i0.862.533.268 (3)144
N8—H8A···Cl2ii0.892.323.180 (3)162
N8—H8B···Cl2iii0.892.373.210 (3)157
C4—H4···Cg1iv0.932.953.772 (5)148
Symmetry codes: (i) x+1/2, y, z+1/2; (ii) x1/2, y+1/2, z; (iii) x+1/2, y+1/2, z+1; (iv) x1/2, y3/2, z.
Acknowledgements top

ASP and PSK are grateful to the Department of Chemistry, Pondicherry University, for the single-crystal XRD instrumentation facility. KA thanks the CSIR, New Delhi (Lr: No. 01 (2570)/12/EMR-II/3.4.2012) for financial support through a major research project.