organic compounds
3,3′-Dimethyl-1,1′-ethylenediimidazolium dibromide
aDepartment of Applied Chemistry, College of Science, Nanjing University of Technology, Nanjing 210009, People's Republic of China
*Correspondence e-mail: danbi@njut.edu.cn
The title compound, C10H16Br2N4, was synthesized by the reaction of 1-methylimidazole and 1,2-dibromoethane in toluene. The complete dication is generated by a crystallographic inversion centre situated at the mid-point of the ethane C—C bond. In the weak intermolecular C—H⋯Br interactions link the molecules into chains along the b axis and an intramolecular C—H⋯Br close contact is also present.
Related literature
For general background, see: Ding et al. (2007). For related literature, see: Peveling (2001); Takao & Kazuhiko (1997). For bond-length data, see: Allen et al. (1987).
Experimental
Crystal data
|
Refinement
|
Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1985); cell CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo,1995); 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.
Supporting information
10.1107/S1600536809036009/at2872sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809036009/at2872Isup2.hkl
The ionic liquid compound was prepared following modified literature procedures (Ding et al., 2007). 1-Methylimidazole (8.21 g, 0.1 mol) was mixed with 1,2-dibromoethane (9.38 g, 0.05 mol) in 100 ml of toluene and refluxed for 24 h; the mixture was cooled to room temperature and filtered. The solids were washed several times with ethyl acetate (800 ml) and the white product dried in vacuum (yield:7.3 g, 54.2%). The product was dissolved in the chloroform and the crystals were obtained by evaporating the chloroform slowly at room temperature for about 9 d.
Carbon-bound H atoms were positioned with idealized geometry [aromatic C—H = 0.93 Å, methylene C—H = 0.97 Å and methyl C—H = 0.96 Å] and refined with fixed isotropic displacement parameters [Uiso(H) = 1.5Ueq(H)(methyl C) and Uiso(H) = 1.2Ueq (aromatic and methylene C)] using a riding model.
Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1985); cell
CAD-4 EXPRESS (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo,1995); 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).C10H16N42+·2Br− | F(000) = 348 |
Mr = 352.07 | Dx = 1.749 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 8.4750 (17) Å | θ = 9–13° |
b = 8.9620 (18) Å | µ = 6.05 mm−1 |
c = 9.2390 (18) Å | T = 293 K |
β = 107.73 (3)° | Square, white |
V = 668.4 (3) Å3 | 0.30 × 0.20 × 0.10 mm |
Z = 2 |
Enraf–Nonius CAD-4 diffractometer | 862 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.021 |
Graphite monochromator | θmax = 25.3°, θmin = 2.5° |
ω/2θ scans | h = 0→10 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→10 |
Tmin = 0.264, Tmax = 0.583 | l = −11→10 |
1296 measured reflections | 3 standard reflections every 200 reflections |
1212 independent reflections | intensity decay: 1% |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.059 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.160 | H-atom parameters constrained |
S = 1.01 | w = 1/[σ2(Fo2) + (0.1P)2 + 0.7P] where P = (Fo2 + 2Fc2)/3 |
1212 reflections | (Δ/σ)max < 0.001 |
73 parameters | Δρmax = 0.80 e Å−3 |
0 restraints | Δρmin = −0.85 e Å−3 |
C10H16N42+·2Br− | V = 668.4 (3) Å3 |
Mr = 352.07 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.4750 (17) Å | µ = 6.05 mm−1 |
b = 8.9620 (18) Å | T = 293 K |
c = 9.2390 (18) Å | 0.30 × 0.20 × 0.10 mm |
β = 107.73 (3)° |
Enraf–Nonius CAD-4 diffractometer | 862 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.021 |
Tmin = 0.264, Tmax = 0.583 | 3 standard reflections every 200 reflections |
1296 measured reflections | intensity decay: 1% |
1212 independent reflections |
R[F2 > 2σ(F2)] = 0.059 | 0 restraints |
wR(F2) = 0.160 | H-atom parameters constrained |
S = 1.01 | Δρmax = 0.80 e Å−3 |
1212 reflections | Δρmin = −0.85 e Å−3 |
73 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > 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. |
x | y | z | Uiso*/Ueq | ||
Br | 0.71826 (11) | 0.14503 (9) | 0.46360 (9) | 0.0320 (3) | |
N1 | 0.8500 (8) | 0.6154 (7) | 0.3322 (7) | 0.0266 (15) | |
C1 | 0.9914 (11) | 0.5837 (12) | 0.2817 (11) | 0.048 (3) | |
H1A | 0.9870 | 0.4818 | 0.2488 | 0.072* | |
H1B | 1.0912 | 0.5997 | 0.3639 | 0.072* | |
H1C | 0.9904 | 0.6486 | 0.1987 | 0.072* | |
N2 | 0.6231 (8) | 0.5865 (7) | 0.3878 (7) | 0.0224 (14) | |
C2 | 0.7287 (9) | 0.5215 (9) | 0.3336 (8) | 0.0235 (17) | |
H2A | 0.7213 | 0.4231 | 0.3003 | 0.028* | |
C3 | 0.6774 (10) | 0.7310 (9) | 0.4270 (9) | 0.0276 (19) | |
H3A | 0.6270 | 0.8023 | 0.4713 | 0.033* | |
C4 | 0.8169 (11) | 0.7482 (9) | 0.3886 (10) | 0.035 (2) | |
H4A | 0.8796 | 0.8349 | 0.3987 | 0.042* | |
C5 | 0.4817 (10) | 0.5171 (10) | 0.4162 (9) | 0.0265 (18) | |
H5A | 0.4544 | 0.4255 | 0.3581 | 0.032* | |
H5B | 0.3869 | 0.5834 | 0.3836 | 0.032* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br | 0.0506 (5) | 0.0167 (5) | 0.0261 (5) | 0.0002 (4) | 0.0081 (4) | −0.0024 (4) |
N1 | 0.039 (4) | 0.018 (4) | 0.024 (3) | −0.007 (3) | 0.011 (3) | −0.008 (3) |
C1 | 0.044 (5) | 0.068 (7) | 0.039 (6) | −0.016 (5) | 0.023 (5) | −0.021 (6) |
N2 | 0.034 (4) | 0.015 (3) | 0.015 (3) | −0.004 (3) | 0.003 (3) | 0.004 (3) |
C2 | 0.033 (4) | 0.017 (4) | 0.018 (4) | −0.005 (3) | 0.004 (3) | −0.008 (3) |
C3 | 0.045 (5) | 0.011 (4) | 0.028 (5) | −0.003 (3) | 0.013 (4) | 0.000 (3) |
C4 | 0.046 (5) | 0.018 (4) | 0.040 (5) | −0.012 (4) | 0.011 (4) | −0.009 (4) |
C5 | 0.029 (4) | 0.026 (4) | 0.024 (4) | −0.010 (3) | 0.007 (3) | 0.001 (4) |
N1—C2 | 1.331 (10) | N2—C5 | 1.443 (9) |
N1—C4 | 1.363 (10) | C2—H2A | 0.9300 |
N1—C1 | 1.441 (10) | C3—C4 | 1.343 (12) |
C1—H1A | 0.9600 | C3—H3A | 0.9300 |
C1—H1B | 0.9600 | C4—H4A | 0.9300 |
C1—H1C | 0.9600 | C5—C5i | 1.514 (15) |
N2—C2 | 1.290 (10) | C5—H5A | 0.9700 |
N2—C3 | 1.386 (10) | C5—H5B | 0.9700 |
C2—N1—C4 | 107.4 (7) | N1—C2—H2A | 124.8 |
C2—N1—C1 | 126.9 (7) | C4—C3—N2 | 106.7 (7) |
C4—N1—C1 | 125.8 (7) | C4—C3—H3A | 126.7 |
N1—C1—H1A | 109.5 | N2—C3—H3A | 126.7 |
N1—C1—H1B | 109.5 | C3—C4—N1 | 107.5 (7) |
H1A—C1—H1B | 109.5 | C3—C4—H4A | 126.2 |
N1—C1—H1C | 109.5 | N1—C4—H4A | 126.2 |
H1A—C1—H1C | 109.5 | N2—C5—C5i | 110.5 (8) |
H1B—C1—H1C | 109.5 | N2—C5—H5A | 109.6 |
C2—N2—C3 | 108.0 (6) | C5i—C5—H5A | 109.6 |
C2—N2—C5 | 126.1 (7) | N2—C5—H5B | 109.6 |
C3—N2—C5 | 125.7 (7) | C5i—C5—H5B | 109.6 |
N2—C2—N1 | 110.3 (7) | H5A—C5—H5B | 108.1 |
N2—C2—H2A | 124.8 | ||
C3—N2—C2—N1 | −0.9 (8) | N2—C3—C4—N1 | −2.0 (9) |
C5—N2—C2—N1 | −175.6 (7) | C2—N1—C4—C3 | 1.5 (10) |
C4—N1—C2—N2 | −0.4 (9) | C1—N1—C4—C3 | −178.1 (8) |
C1—N1—C2—N2 | 179.2 (8) | C2—N2—C5—C5i | 101.3 (10) |
C2—N2—C3—C4 | 1.8 (9) | C3—N2—C5—C5i | −72.4 (11) |
C5—N2—C3—C4 | 176.5 (7) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2A···Br | 0.93 | 2.92 | 3.591 (8) | 130 |
C1—H1B···Brii | 0.96 | 2.97 | 3.738 (8) | 138 |
Symmetry code: (ii) −x+2, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C10H16N42+·2Br− |
Mr | 352.07 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 8.4750 (17), 8.9620 (18), 9.2390 (18) |
β (°) | 107.73 (3) |
V (Å3) | 668.4 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 6.05 |
Crystal size (mm) | 0.30 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.264, 0.583 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1296, 1212, 862 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.601 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.059, 0.160, 1.01 |
No. of reflections | 1212 |
No. of parameters | 73 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.80, −0.85 |
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo,1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2A···Br | 0.9300 | 2.9200 | 3.591 (8) | 130.00 |
C1—H1B···Bri | 0.9600 | 2.9690 | 3.738 (8) | 138.07 |
Symmetry code: (i) −x+2, −y+1, −z+1. |
Acknowledgements
The authors thank the Center of Testing and Analysis, Nanjing University, for support.
References
Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
Ding, Y. S., Zha, M., Zhang, J. & Wang, S. S. (2007). Colloids Surf. A: Physicochem. Eng. 298, 201–205. Google Scholar
Enraf–Nonius (1985). CAD-4 Software. Enraf-Nonius, Delft,The Netherlands. Google Scholar
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany. Google Scholar
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359. CrossRef IUCr Journals Web of Science Google Scholar
Peveling, R. (2001). J. Orthopt. Res. 10, 171–187. CrossRef Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Takao, S. & Kazuhiko, M. (1997). Takasago International Corporation, Tokyo, Japan. EP Patent No. 0 755 937. Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound is a kind of ionic liquids to be used as green alternatives to volatile organic solvents inelectrochemical, synthetic and separation processes. For general background, see: (Ding et al., 2007). We herein report the crystal structure of the title compound (I).
In the molecule of (I), (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. The whole molecule has an inversion symmetry located on the ethane group of the main molecule.
In the crystal structure, weak intermolecular C—H···Br interactions (Table 1) link the molecules into chains along the b axis (Fig.2), in which they may be effective in the stabilization of the structure.