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Acta Cryst. (2012). E68, m17    [ doi:10.1107/S1600536811051828 ]

2-Bromo-1,3-diisopropyl-4,5-dimethyl-1H-imidazol-3-ium dicyanidoargentate

E. Mallah, K. Sweidan, Q. Abu-Salem, W. Abu Dayyih and M. Steimann

Abstract top

The title structure, (C11H20BrN2)[Ag(CN)2)], is built up from an approximately C2v-symmetric imidazolium cation and a nearly linear dicyanidoargentate anion [N-Ag-N = 176.6 (9)° and Ag-C-N = 178.8 (9) and 177.2 (11)°]. These two constituents are linked by a remarkably short interaction between the Br atom of the imidazolium cation [C-Br = 1.85 (3) Å] and one N atom of the cyanidoargentate anion [Br...N = 2.96 (2) Å], which is much less than the sum of the van der Waals radii (3.40 Å). The crystal studied was twinned by merohedry.

Comment top

N-heterocyclic carbenes can form stable coordination compounds with main group elements by using their strongly basic character. Kuhn et al. (2004) showed that weak interionic halogen contacts between 2-haloimidazolium cations and halogen containing counter anions do exist in the solid state. Results of related investigations were reported by Kuhn et al. (2009), Mallah et al. (2009), and Potocenak & Chomic (2006). The reaction of 2-bromo-1,3-diisopropyl-4,5-dimethylimidazolium bromide with silver cyanide gives the title compound as stable crystalline solid in a good yield. The structure contains an approximately C2v imidazolium cation (Fig. 1), similar to the crystal structure of the 2-chloroimidazolium analogue (Mallah et al., 2011), where the C—Cl bond (1.677 (5) Å) is shorter than the C—Br bond of the title compound (1.848 (6) Å). The title structure contains a cation-anion pair (Fig. 1) with a short N(12)(x-1,y,z)···Br(1) interaction of 2.96 (2) Å, by ca. 0.4 Å shorther than the sum of the van der Waals radii. Mascal et al. (1996) found for a s-triazine–dibromine cocrystal a N···Br contact distance as short as 2.515 Å.

Related literature top

For similar structures, see: Mallah et al. (2009, 2011); Kuhn et al. (2009); Potocenak & Chomic (2006); Mascal et al. (1996). For the synthesis of the starting material, see: Kuhn et al. (2004).

Experimental top

The title compound was prepared by addition of silver cyanide (1.3 g, 9.7 mmol) to a solution of 2-bromo-1,3-diisopropyl-4,5-dimethylimidazoliumbromide, see: Kuhn et al. (2004), (1.1 g, 3.2 mmol) in 30 ml of acetonitrile. The mixture was stirred for 48 hr at room temperature, then the solvent was removed in vacuo and 20 ml of dichloromethane was added. The resulting solution was filtered off and solvent was removed in vacuo. Yield after recrystallisation from dichloromethane/diethyl ether 0.98 g (73 %), as colorless crystals.

Refinement top

There are no Friedel pairs because only the minimal data set was measured with the CAD4 instrument (±h, +k, +l). Hydrogen atoms were included at calculated positions with C—H = 0.95–1.00 Å and 1.5Ueq(aliphatic C), using a riding-model approximation.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CELDIM (Enraf–Nonius, 1989); data reduction: HELENA/PLATON (Spek, 2009),; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure the cation-anion pair of the title compound showing 20% probability displacement ellipsoids for non-H atoms. The symmetry transformation for the depicted dicyanoargentate anion is x-1, y, z.
2-Bromo-1,3-diisopropyl-4,5-dimethyl-1H-imidazol-3-ium dicyanidoargentate top
Crystal data top
(C11H20BrN2)[Ag(CN)2)]F(000) = 832
Mr = 420.11Dx = 1.635 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 25 reflections
a = 6.6986 (15) Åθ = 6.7–13.0°
b = 10.6222 (14) ŵ = 3.52 mm1
c = 23.989 (4) ÅT = 291 K
V = 1706.9 (5) Å3Block, colourless
Z = 40.40 × 0.20 × 0.20 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
1781 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.052
graphiteθmax = 26.4°, θmin = 3.2°
ω scansh = 88
Absorption correction: part of the refinement model (ΔF)
(DIFABS; Walker & Stuart, 1983)
k = 113
Tmin = 0.40, Tmax = 1.00l = 129
4327 measured reflections3 standard reflections every 300 reflections
3475 independent reflections intensity decay: 1.5%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.052H-atom parameters constrained
wR(F2) = 0.082 w = 1/[σ2(Fo2) + (0.0199P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max = 0.001
3475 reflectionsΔρmax = 0.33 e Å3
180 parametersΔρmin = 0.46 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00128 (16)
Crystal data top
(C11H20BrN2)[Ag(CN)2)]V = 1706.9 (5) Å3
Mr = 420.11Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 6.6986 (15) ŵ = 3.52 mm1
b = 10.6222 (14) ÅT = 291 K
c = 23.989 (4) Å0.40 × 0.20 × 0.20 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
1781 reflections with I > 2σ(I)
Absorption correction: part of the refinement model (ΔF)
(DIFABS; Walker & Stuart, 1983)
Rint = 0.052
Tmin = 0.40, Tmax = 1.00θmax = 26.4°
4327 measured reflections3 standard reflections every 300 reflections
3475 independent reflections intensity decay: 1.5%
Refinement top
R[F2 > 2σ(F2)] = 0.052H-atom parameters constrained
wR(F2) = 0.082Δρmax = 0.33 e Å3
S = 0.98Δρmin = 0.46 e Å3
3475 reflectionsAbsolute structure: ?
180 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
Ag10.71941 (9)0.98742 (7)0.12744 (3)0.0718 (2)
C10.6144 (9)0.5300 (5)0.1252 (3)0.0411 (16)
N20.7155 (9)0.5116 (6)0.0780 (2)0.0417 (16)
C30.8807 (12)0.4401 (6)0.0898 (3)0.045 (2)
C40.8812 (11)0.4187 (7)0.1450 (3)0.048 (2)
N50.7109 (9)0.4757 (6)0.1669 (2)0.0470 (16)
C110.5572 (13)1.1454 (10)0.1123 (4)0.072 (3)
C120.8919 (14)0.8303 (9)0.1400 (4)0.073 (3)
C210.6467 (13)0.5572 (8)0.0225 (3)0.059 (2)
H210.52330.60410.02960.071*
C220.7867 (15)0.6484 (9)0.0028 (3)0.092 (3)
H22A0.82890.70790.02490.138*
H22B0.72120.69210.03270.138*
H22C0.90100.60440.01710.138*
C230.5874 (13)0.4462 (9)0.0143 (3)0.087 (3)
H23A0.70510.40200.02600.131*
H23B0.51700.47660.04650.131*
H23C0.50270.39020.00630.131*
C311.0326 (11)0.3991 (9)0.0475 (3)0.076 (3)
H31A1.13490.35080.06560.115*
H31B1.09100.47190.03030.115*
H31C0.96890.34840.01960.115*
C411.0252 (11)0.3428 (9)0.1781 (3)0.085 (3)
H41A1.12370.30720.15370.128*
H41B0.95530.27630.19690.128*
H41C1.08960.39570.20510.128*
C510.6523 (12)0.4807 (8)0.2263 (3)0.056 (2)
H510.52820.52960.22660.067*
C520.5934 (14)0.3535 (9)0.2481 (3)0.089 (3)
H52A0.51760.30960.22020.133*
H52B0.51380.36350.28110.133*
H52C0.71120.30600.25690.133*
C530.7912 (14)0.5544 (8)0.2608 (3)0.086 (3)
H53A0.90730.50470.26880.129*
H53B0.72670.57760.29500.129*
H53C0.83010.62900.24100.129*
N110.4683 (10)1.2343 (8)0.1047 (3)0.076 (2)
N120.9891 (11)0.7474 (8)0.1450 (4)0.090 (3)
Br10.37724 (11)0.61731 (7)0.13261 (3)0.0596 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ag10.0664 (4)0.0772 (5)0.0718 (4)0.0139 (4)0.0084 (4)0.0021 (5)
C10.040 (4)0.032 (4)0.051 (4)0.001 (3)0.002 (5)0.007 (5)
N20.040 (3)0.053 (4)0.033 (3)0.010 (4)0.003 (3)0.001 (4)
C30.050 (5)0.043 (5)0.042 (5)0.008 (4)0.005 (4)0.004 (4)
C40.037 (4)0.052 (5)0.054 (5)0.003 (4)0.007 (4)0.010 (4)
N50.046 (3)0.053 (4)0.042 (3)0.003 (4)0.001 (3)0.009 (4)
C110.070 (7)0.077 (8)0.069 (7)0.017 (5)0.009 (5)0.001 (6)
C120.077 (6)0.069 (7)0.072 (7)0.005 (5)0.015 (6)0.009 (6)
C210.057 (5)0.070 (6)0.050 (5)0.016 (5)0.005 (4)0.010 (5)
C220.106 (8)0.100 (9)0.070 (6)0.029 (7)0.004 (6)0.030 (6)
C230.081 (6)0.108 (9)0.073 (6)0.010 (6)0.026 (6)0.013 (6)
C310.061 (5)0.104 (8)0.063 (5)0.024 (6)0.003 (4)0.011 (6)
C410.072 (6)0.112 (9)0.072 (6)0.031 (6)0.012 (5)0.023 (6)
C510.063 (6)0.062 (6)0.042 (4)0.007 (6)0.003 (4)0.006 (5)
C520.104 (8)0.100 (9)0.061 (6)0.016 (7)0.022 (6)0.010 (6)
C530.112 (8)0.094 (8)0.052 (5)0.028 (7)0.008 (5)0.013 (5)
N110.069 (5)0.079 (6)0.079 (5)0.009 (5)0.001 (4)0.006 (5)
N120.082 (6)0.071 (6)0.117 (8)0.005 (5)0.002 (5)0.001 (6)
Br10.0552 (5)0.0610 (5)0.0624 (5)0.0161 (4)0.0033 (5)0.0025 (6)
Geometric parameters (Å, °) top
Ag1—C112.032 (10)C22—H22C0.9600
Ag1—C122.053 (10)C23—H23A0.9600
C1—N51.325 (7)C23—H23B0.9600
C1—N21.332 (7)C23—H23C0.9600
C1—Br11.848 (6)C31—H31A0.9600
N2—C31.371 (8)C31—H31B0.9600
N2—C211.490 (8)C31—H31C0.9600
C3—C41.344 (8)C41—H41A0.9600
C3—C311.501 (10)C41—H41B0.9600
C4—N51.394 (8)C41—H41C0.9600
C4—C411.486 (9)C51—C531.471 (11)
N5—C511.478 (8)C51—C521.502 (11)
C11—N111.131 (10)C51—H510.9800
C12—N121.102 (10)C52—H52A0.9600
C21—C221.479 (10)C52—H52B0.9600
C21—C231.526 (10)C52—H52C0.9600
C21—H210.9800C53—H53A0.9600
C22—H22A0.9600C53—H53B0.9600
C22—H22B0.9600C53—H53C0.9600
C11—Ag1—C12177.5 (4)C21—C23—H23C109.5
N5—C1—N2109.2 (5)H23A—C23—H23C109.5
N5—C1—Br1124.4 (6)H23B—C23—H23C109.5
N2—C1—Br1126.4 (6)C3—C31—H31A109.5
C1—N2—C3108.5 (5)C3—C31—H31B109.5
C1—N2—C21123.6 (6)H31A—C31—H31B109.5
C3—N2—C21127.9 (6)C3—C31—H31C109.5
C4—C3—N2107.4 (7)H31A—C31—H31C109.5
C4—C3—C31127.9 (8)H31B—C31—H31C109.5
N2—C3—C31124.6 (6)C4—C41—H41A109.5
C3—C4—N5107.2 (7)C4—C41—H41B109.5
C3—C4—C41128.3 (8)H41A—C41—H41B109.5
N5—C4—C41124.4 (6)C4—C41—H41C109.5
C1—N5—C4107.7 (5)H41A—C41—H41C109.5
C1—N5—C51125.7 (6)H41B—C41—H41C109.5
C4—N5—C51126.6 (6)C53—C51—N5113.2 (7)
N11—C11—Ag1178.8 (9)C53—C51—C52116.7 (7)
N12—C12—Ag1177.2 (11)N5—C51—C52111.9 (7)
C22—C21—N2112.6 (7)C53—C51—H51104.5
C22—C21—C23115.7 (7)N5—C51—H51104.5
N2—C21—C23110.3 (6)C52—C51—H51104.5
C22—C21—H21105.8C51—C52—H52A109.5
N2—C21—H21105.8C51—C52—H52B109.5
C23—C21—H21105.8H52A—C52—H52B109.5
C21—C22—H22A109.5C51—C52—H52C109.5
C21—C22—H22B109.5H52A—C52—H52C109.5
H22A—C22—H22B109.5H52B—C52—H52C109.5
C21—C22—H22C109.5C51—C53—H53A109.5
H22A—C22—H22C109.5C51—C53—H53B109.5
H22B—C22—H22C109.5H53A—C53—H53B109.5
C21—C23—H23A109.5C51—C53—H53C109.5
C21—C23—H23B109.5H53A—C53—H53C109.5
H23A—C23—H23B109.5H53B—C53—H53C109.5
N5—C1—N2—C31.5 (7)Br1—C1—N5—C513.3 (10)
Br1—C1—N2—C3178.6 (5)C3—C4—N5—C10.5 (8)
N5—C1—N2—C21178.3 (6)C41—C4—N5—C1177.2 (7)
Br1—C1—N2—C211.8 (9)C3—C4—N5—C51177.7 (7)
C1—N2—C3—C41.8 (8)C41—C4—N5—C515.7 (12)
C21—N2—C3—C4178.5 (7)C12—Ag1—C11—N11100 (52)
C1—N2—C3—C31180.0 (7)C11—Ag1—C12—N125(30)
C21—N2—C3—C313.3 (12)C1—N2—C21—C22118.1 (8)
N2—C3—C4—N51.4 (8)C3—N2—C21—C2265.7 (10)
C31—C3—C4—N5179.5 (7)C1—N2—C21—C23111.1 (8)
N2—C3—C4—C41177.9 (7)C3—N2—C21—C2365.2 (10)
C31—C3—C4—C414.0 (14)C1—N5—C51—C53111.4 (8)
N2—C1—N5—C40.6 (8)C4—N5—C51—C5365.2 (11)
Br1—C1—N5—C4179.5 (5)C1—N5—C51—C52114.3 (9)
N2—C1—N5—C51176.6 (7)C4—N5—C51—C5269.0 (10)
Acknowledgements top

The authors are grateful to the Deutsche Forschungsgemeinschaft, the Higher Council for Science and Technology of Jordan and Petra University for financial support. We also thank Dr Cäcilia Maichle-Mössmer for helpful discussions.

references
References top

Enraf–Nonius (1989). CAD-4 Software. Enraf–Nonius, Delft, The Netherlands.

Flack, H. D. (1983). Acta Cryst. A39, 876–881.

Kuhn, N., Abu-Rayyan, A., Eichele, K., Schwarz, S. & Steimann, M. (2004). Inorg. Chim. Acta, 357, 1799–1804.

Kuhn, N., Mallah, E., Maichle-Mössmer, C. & Steimann, M. (2009). Z. Naturforsch. Teil B, 64, 835–839.

Mallah, E., Abu-Salem, Q., Sweidan, K., Kuhn, N., Maichle-Mössmer, C., Steimann, M., Ströbele, M. & Walker, M. (2011). Z. Naturforsch. Teil B, 66, 545–548.

Mallah, E., Kuhn, N., Maichle-Mössmer, C., Steimann, M., Ströbele, M. & Zeller, K. P. (2009). Z. Naturforsch. Teil B, 64, 1176–1182.

Mascal, M., Richardson, J. L., Blake, A. J. & Li, W.-S. (1996). Tetrahedron Lett. 37, 3505–3506.

Potocenak, I. & Chomic, J. (2006). Transition Met. Chem. 31, 504–515.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Spek, A. L. (2009). Acta Cryst. D65, 148–155.

Walker, N. & Stuart, D. (1983). Acta Cryst. A39, 158–166.