organic compounds
3,3′-(Hexane-1,6-diyl)bis(1-vinyl-4-imidazoline-2-thione)
aUniversity of Innsbruck, Faculty of Chemistry and Pharmacy, Innrain 80, 6020 Innsbruck, Austria, and bUniversity of Innsbruck, Institute of Mineralogy and Petrography, Innrain 52, 6020 Innsbruck, Austria
*Correspondence e-mail: herwig.schottenberger@uibk.ac.at
The title compound, C16H22N4S2, was obtained by the reaction of sulfur with the corresponding quaternary salt in the presence of K2CO3. It crystallizes with two half-molecules in the the complete molecules are generated by inversion symmetry with the central CH2—CH2 bonds of the hexane bridges being located on inversion centres. In each molecule, the C6-alkyl chain adopts a typical antiperiplanar conformation and the two heterocyclic rings are oriented antiparallel to each other. In the crystal, molecules are linked by C—H⋯π interactions, forming layers lying parallel to the ac plane.
Keywords: crystal structure; cross-linker; imidazole; poly(ionic liquid); thione; vinyl; C—H⋯π interactions.
CCDC reference: 1545075
Structure description
The title compound was obtained from 3,3′-(hexane-1,6-diyl)bis(1-vinylimidazolium) dibromide (Cui et al., 2014) by reaction with elemental sulfur in the presence of K2CO3. Imidazoline-2-thiones (Laus et al., 2013) are versatile building blocks whose properties have been reviewed by Trzhtsinskaya & Abramova (1991). The crucial advantages of these thiones are simple synthesis and simple derivation in the realm of imidazole chemistry, a mainstay of ionic liquid research. A field of current relevance, poly(ionic liquids) are macromolecules derived from organic salts which are liquid below 373 K (Yuan & Antonietti, 2011). The vinyl substituent renders the title molecule polymerizable, and the bidentate nature of the molecule facilitates cross-linking, thus giving access to a plethora of functionalized imidazolium-containing polymers (Anderson & Long, 2010). They in turn offer a multitude of applications and represent major advances in materials science.
The ), which are completed by inversion symmetry. The centres of symmetry lie at the mid-point of the (CH2)6 spacer between the two imidazoline-2-thione rings. As in other bridged bis(imidazoline-2-thiones), the C6-alkyl chain adopts a typical antiperiplanar conformation (Bhabak et al., 2011; Beheshti et al., 2016), and the two heterocyclic rings are oriented antiparallel to each other, as can be seen in Fig. 1. The lengths of the C=S bonds are 1.680 (1) and 1.682 (1) Å, in perfect accordance with the mean value (Laus et al., 2013) in the Cambridge Structural Database (Groom et al., 2016). Related structures have been reported with short methylene or ethylene bridges (Liu et al., 2003; Jia et al., 2008), C3-to-C5 bridges (Bhabak et al., 2011; Beheshti et al., 2016), and longer linkers (Marshall et al., 2005; Marshall & Harrison, 2007).
contains two independent half-molecules (Fig. 1In the crystal, molecules are linked by C—H⋯π interactions, forming layers lying parallel to the ac plane (Table 1 and Fig. 2).
Synthesis and crystallization
A mixture of 3,3′-(hexane-1,6-diyl)bis(1-vinylimidazolium) dibromide (55.6 g, 129 mmol), sulfur (8.25 g, 257 mmol) and K2CO3 (35.6 g, 257 mmol) in MeOH (200 ml) was refluxed for 3 h. After evaporation of the solvent under reduced pressure, the residue was extracted with hot CHCl3 (3 × 250 ml), followed by hot filtration and evaporation of the solvent. To the residue, EtOH (200 ml) was added and the mixture was ultrasonicated for 30 min. The product was collected by filtration and dried in high vacuum for 24 h (yield 40.0 g, 93%; m.p. 423 K). Single crystals were obtained by slow evaporation of a CHCl3 solution. 1H NMR (300 MHz, CDCl3): δ 1.29 (m, 4H), 1.68 (m, 4H), 3.92 (t, J = 7.4 Hz, 4H), 4.80 (dd, J = 9.0, 1.8 Hz, 2H), 5.05 (dd, J = 16.1, 1.8 Hz, 2H), 6.68 (d, J = 2.6 Hz, 2H), 6.91 (d, J = 2.6 Hz, 2H), 7.44 (dd, J = 16.1, 9.0 Hz, 2H) p.p.m. 13C NMR (75 MHz, CDCl3): δ 25.7, 28.2, 47.2, 100.6, 112.4, 118.1, 130.0, 162.3 p.p.m. IR (neat): ν 3126, 3092, 2943, 2855, 1639, 1454, 1421, 1401, 1363, 1288, 1259, 1233, 1160, 975, 875, 831, 762, 742, 718, 697, 659, 518, 486 cm−1.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1545075
https://doi.org/10.1107/S2414314617005995/su4149sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617005995/su4149Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314617005995/su4149Isup3.mol
Supporting information file. DOI: https://doi.org/10.1107/S2414314617005995/su4149Isup4.cml
Data collection: (CrysAlis PRO; Agilent, 2014); cell
(CrysAlis PRO; Agilent, 2014); data reduction: (CrysAlis PRO; Agilent, 2014); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).C16H22N4S2 | Z = 2 |
Mr = 334.5 | F(000) = 356 |
Triclinic, P1 | Dx = 1.279 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.1335 (5) Å | Cell parameters from 3343 reflections |
b = 10.6863 (5) Å | θ = 4.0–28.5° |
c = 11.8830 (6) Å | µ = 0.31 mm−1 |
α = 99.856 (4)° | T = 173 K |
β = 93.530 (5)° | Prismatic fragment, colourless |
γ = 101.937 (5)° | 0.54 × 0.2 × 0.14 mm |
V = 868.75 (9) Å3 |
Agilent Xcalibur Ruby Gemini ultra diffractometer | 3151 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 2821 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.013 |
Detector resolution: 10.3575 pixels mm-1 | θmax = 25.4°, θmin = 3.5° |
ω scans | h = −6→8 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014) | k = −12→11 |
Tmin = 0.880, Tmax = 1 | l = −14→13 |
5545 measured reflections |
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)] = 0.029 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.072 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0287P)2 + 0.3242P] where P = (Fo2 + 2Fc2)/3 |
3151 reflections | (Δ/σ)max = 0.001 |
199 parameters | Δρmax = 0.20 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.42181 (5) | 0.23294 (4) | 0.56557 (3) | 0.03198 (11) | |
S2 | −0.05723 (5) | 0.23677 (4) | 0.07703 (3) | 0.03264 (11) | |
N4 | 0.22259 (16) | 0.40254 (11) | 0.23089 (10) | 0.0230 (3) | |
N3 | 0.28775 (16) | 0.21338 (11) | 0.17699 (10) | 0.0234 (3) | |
N2 | 0.16867 (17) | 0.19534 (11) | 0.72562 (10) | 0.0237 (3) | |
N1 | 0.02845 (16) | 0.16137 (10) | 0.55287 (10) | 0.0216 (2) | |
C1 | 0.20569 (19) | 0.19571 (12) | 0.61534 (11) | 0.0212 (3) | |
C14 | 0.1222 (2) | 0.50945 (14) | 0.24615 (12) | 0.0270 (3) | |
H14A | 0.0525 | 0.5112 | 0.172 | 0.032* | |
H14B | 0.2178 | 0.593 | 0.2699 | 0.032* | |
C9 | 0.15171 (19) | 0.28462 (13) | 0.16221 (11) | 0.0231 (3) | |
C7 | 0.3279 (2) | 0.37721 (14) | 0.87953 (12) | 0.0268 (3) | |
H7A | 0.2061 | 0.3851 | 0.9129 | 0.032* | |
H7B | 0.3436 | 0.4314 | 0.8195 | 0.032* | |
C8 | 0.4943 (2) | 0.42931 (14) | 0.97290 (12) | 0.0269 (3) | |
H8A | 0.6164 | 0.422 | 0.9397 | 0.032* | |
H8B | 0.479 | 0.3754 | 1.0331 | 0.032* | |
C11 | 0.3978 (2) | 0.40436 (14) | 0.28805 (12) | 0.0263 (3) | |
H11 | 0.475 | 0.4756 | 0.3414 | 0.032* | |
C10 | 0.4393 (2) | 0.28843 (14) | 0.25507 (12) | 0.0268 (3) | |
H10 | 0.5515 | 0.262 | 0.2802 | 0.032* | |
C15 | −0.0198 (2) | 0.49571 (14) | 0.33577 (12) | 0.0252 (3) | |
H15A | −0.1108 | 0.41 | 0.3133 | 0.03* | |
H15B | −0.0952 | 0.5638 | 0.3362 | 0.03* | |
C12 | 0.2730 (2) | 0.08475 (14) | 0.11905 (13) | 0.0279 (3) | |
H12 | 0.1562 | 0.0426 | 0.0729 | 0.033* | |
C13 | 0.4068 (3) | 0.01920 (17) | 0.12376 (17) | 0.0465 (5) | |
H13A | 0.5258 | 0.0579 | 0.169 | 0.056* | |
H13B | 0.3857 | −0.0675 | 0.082 | 0.056* | |
C16 | 0.07338 (19) | 0.50680 (13) | 0.45661 (12) | 0.0240 (3) | |
H16A | 0.1478 | 0.4383 | 0.457 | 0.029* | |
H16B | 0.1645 | 0.5924 | 0.4796 | 0.029* | |
C6 | 0.3136 (2) | 0.23646 (14) | 0.82447 (12) | 0.0292 (3) | |
H6A | 0.4403 | 0.2258 | 0.7997 | 0.035* | |
H6B | 0.2797 | 0.1803 | 0.8817 | 0.035* | |
C5 | −0.1648 (2) | 0.12107 (15) | 0.37121 (14) | 0.0354 (4) | |
H5A | −0.2801 | 0.1019 | 0.407 | 0.042* | |
H5B | −0.1707 | 0.1173 | 0.2906 | 0.042* | |
C3 | −0.0276 (2) | 0.16310 (14) | 0.73221 (13) | 0.0287 (3) | |
H3 | −0.0894 | 0.1575 | 0.8003 | 0.034* | |
C2 | −0.1148 (2) | 0.14119 (14) | 0.62602 (13) | 0.0275 (3) | |
H2 | −0.2497 | 0.1164 | 0.6044 | 0.033* | |
C4 | 0.0022 (2) | 0.15270 (13) | 0.43297 (12) | 0.0260 (3) | |
H4 | 0.1142 | 0.1712 | 0.3941 | 0.031* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.02078 (19) | 0.0399 (2) | 0.0333 (2) | 0.00365 (15) | 0.00389 (15) | 0.00479 (17) |
S2 | 0.0251 (2) | 0.0409 (2) | 0.0281 (2) | 0.00743 (16) | −0.00448 (15) | −0.00125 (16) |
N4 | 0.0222 (6) | 0.0255 (6) | 0.0207 (6) | 0.0046 (5) | 0.0047 (5) | 0.0026 (5) |
N3 | 0.0205 (6) | 0.0255 (6) | 0.0233 (6) | 0.0037 (5) | 0.0020 (5) | 0.0037 (5) |
N2 | 0.0252 (6) | 0.0235 (6) | 0.0210 (6) | 0.0047 (5) | −0.0004 (5) | 0.0025 (5) |
N1 | 0.0202 (6) | 0.0207 (6) | 0.0229 (6) | 0.0043 (4) | −0.0004 (5) | 0.0027 (4) |
C1 | 0.0229 (7) | 0.0174 (6) | 0.0227 (7) | 0.0053 (5) | −0.0008 (5) | 0.0018 (5) |
C14 | 0.0310 (8) | 0.0257 (7) | 0.0262 (7) | 0.0091 (6) | 0.0047 (6) | 0.0059 (6) |
C9 | 0.0224 (7) | 0.0277 (7) | 0.0194 (7) | 0.0041 (6) | 0.0060 (5) | 0.0052 (5) |
C7 | 0.0282 (7) | 0.0297 (8) | 0.0209 (7) | 0.0040 (6) | −0.0020 (6) | 0.0048 (6) |
C8 | 0.0273 (7) | 0.0335 (8) | 0.0188 (7) | 0.0041 (6) | −0.0005 (6) | 0.0059 (6) |
C11 | 0.0217 (7) | 0.0307 (8) | 0.0227 (7) | 0.0000 (6) | 0.0014 (6) | 0.0023 (6) |
C10 | 0.0212 (7) | 0.0310 (8) | 0.0265 (8) | 0.0038 (6) | −0.0011 (6) | 0.0045 (6) |
C15 | 0.0248 (7) | 0.0248 (7) | 0.0265 (7) | 0.0084 (6) | 0.0035 (6) | 0.0020 (6) |
C12 | 0.0269 (8) | 0.0253 (7) | 0.0289 (8) | 0.0019 (6) | 0.0024 (6) | 0.0029 (6) |
C13 | 0.0357 (9) | 0.0348 (9) | 0.0623 (12) | 0.0109 (7) | −0.0056 (8) | −0.0091 (8) |
C16 | 0.0218 (7) | 0.0231 (7) | 0.0262 (7) | 0.0056 (5) | 0.0035 (6) | 0.0016 (6) |
C6 | 0.0327 (8) | 0.0325 (8) | 0.0219 (7) | 0.0077 (6) | −0.0047 (6) | 0.0053 (6) |
C5 | 0.0386 (9) | 0.0352 (8) | 0.0305 (8) | 0.0084 (7) | −0.0077 (7) | 0.0045 (7) |
C3 | 0.0280 (8) | 0.0278 (7) | 0.0303 (8) | 0.0044 (6) | 0.0078 (6) | 0.0058 (6) |
C2 | 0.0198 (7) | 0.0268 (7) | 0.0350 (8) | 0.0038 (6) | 0.0035 (6) | 0.0044 (6) |
C4 | 0.0316 (8) | 0.0219 (7) | 0.0237 (7) | 0.0066 (6) | −0.0004 (6) | 0.0024 (6) |
S1—C1 | 1.6805 (14) | C8—H8B | 0.99 |
S2—C9 | 1.6820 (14) | C11—C10 | 1.333 (2) |
N4—C9 | 1.3576 (18) | C11—H11 | 0.95 |
N4—C11 | 1.3799 (18) | C10—H10 | 0.95 |
N4—C14 | 1.4609 (18) | C15—C16 | 1.5196 (19) |
N3—C9 | 1.3721 (18) | C15—H15A | 0.99 |
N3—C10 | 1.3914 (18) | C15—H15B | 0.99 |
N3—C12 | 1.4078 (18) | C12—C13 | 1.299 (2) |
N2—C1 | 1.3531 (18) | C12—H12 | 0.95 |
N2—C3 | 1.3812 (18) | C13—H13A | 0.95 |
N2—C6 | 1.4585 (18) | C13—H13B | 0.95 |
N1—C1 | 1.3724 (17) | C16—C16ii | 1.517 (3) |
N1—C2 | 1.3889 (18) | C16—H16A | 0.99 |
N1—C4 | 1.4101 (18) | C16—H16B | 0.99 |
C14—C15 | 1.5188 (19) | C6—H6A | 0.99 |
C14—H14A | 0.99 | C6—H6B | 0.99 |
C14—H14B | 0.99 | C5—C4 | 1.309 (2) |
C7—C6 | 1.514 (2) | C5—H5A | 0.95 |
C7—C8 | 1.5178 (19) | C5—H5B | 0.95 |
C7—H7A | 0.99 | C3—C2 | 1.333 (2) |
C7—H7B | 0.99 | C3—H3 | 0.95 |
C8—C8i | 1.521 (3) | C2—H2 | 0.95 |
C8—H8A | 0.99 | C4—H4 | 0.95 |
C9—N4—C11 | 110.30 (12) | C11—C10—N3 | 107.23 (13) |
C9—N4—C14 | 124.54 (12) | C11—C10—H10 | 126.4 |
C11—N4—C14 | 125.10 (12) | N3—C10—H10 | 126.4 |
C9—N3—C10 | 109.60 (12) | C14—C15—C16 | 114.16 (12) |
C9—N3—C12 | 123.89 (12) | C14—C15—H15A | 108.7 |
C10—N3—C12 | 126.51 (12) | C16—C15—H15A | 108.7 |
C1—N2—C3 | 110.19 (12) | C14—C15—H15B | 108.7 |
C1—N2—C6 | 124.83 (12) | C16—C15—H15B | 108.7 |
C3—N2—C6 | 124.68 (12) | H15A—C15—H15B | 107.6 |
C1—N1—C2 | 109.63 (11) | C13—C12—N3 | 125.10 (14) |
C1—N1—C4 | 123.53 (12) | C13—C12—H12 | 117.4 |
C2—N1—C4 | 126.82 (12) | N3—C12—H12 | 117.4 |
N2—C1—N1 | 105.20 (11) | C12—C13—H13A | 120 |
N2—C1—S1 | 127.50 (10) | C12—C13—H13B | 120 |
N1—C1—S1 | 127.29 (10) | H13A—C13—H13B | 120 |
N4—C14—C15 | 111.76 (11) | C16ii—C16—C15 | 112.40 (14) |
N4—C14—H14A | 109.3 | C16ii—C16—H16A | 109.1 |
C15—C14—H14A | 109.3 | C15—C16—H16A | 109.1 |
N4—C14—H14B | 109.3 | C16ii—C16—H16B | 109.1 |
C15—C14—H14B | 109.3 | C15—C16—H16B | 109.1 |
H14A—C14—H14B | 107.9 | H16A—C16—H16B | 107.9 |
N4—C9—N3 | 105.07 (12) | N2—C6—C7 | 111.33 (12) |
N4—C9—S2 | 127.37 (11) | N2—C6—H6A | 109.4 |
N3—C9—S2 | 127.56 (11) | C7—C6—H6A | 109.4 |
C6—C7—C8 | 113.07 (12) | N2—C6—H6B | 109.4 |
C6—C7—H7A | 109 | C7—C6—H6B | 109.4 |
C8—C7—H7A | 109 | H6A—C6—H6B | 108 |
C6—C7—H7B | 109 | C4—C5—H5A | 120 |
C8—C7—H7B | 109 | C4—C5—H5B | 120 |
H7A—C7—H7B | 107.8 | H5A—C5—H5B | 120 |
C7—C8—C8i | 112.14 (15) | C2—C3—N2 | 107.85 (13) |
C7—C8—H8A | 109.2 | C2—C3—H3 | 126.1 |
C8i—C8—H8A | 109.2 | N2—C3—H3 | 126.1 |
C7—C8—H8B | 109.2 | C3—C2—N1 | 107.13 (12) |
C8i—C8—H8B | 109.2 | C3—C2—H2 | 126.4 |
H8A—C8—H8B | 107.9 | N1—C2—H2 | 126.4 |
C10—C11—N4 | 107.79 (12) | C5—C4—N1 | 124.94 (14) |
C10—C11—H11 | 126.1 | C5—C4—H4 | 117.5 |
N4—C11—H11 | 126.1 | N1—C4—H4 | 117.5 |
C3—N2—C1—N1 | −0.75 (15) | C9—N4—C11—C10 | 0.59 (15) |
C6—N2—C1—N1 | −174.72 (12) | C14—N4—C11—C10 | 177.66 (12) |
C3—N2—C1—S1 | 178.20 (10) | N4—C11—C10—N3 | −0.32 (15) |
C6—N2—C1—S1 | 4.2 (2) | C9—N3—C10—C11 | −0.04 (16) |
C2—N1—C1—N2 | 0.35 (14) | C12—N3—C10—C11 | 178.96 (13) |
C4—N1—C1—N2 | 178.70 (11) | N4—C14—C15—C16 | 65.34 (16) |
C2—N1—C1—S1 | −178.60 (10) | C9—N3—C12—C13 | 173.65 (16) |
C4—N1—C1—S1 | −0.25 (19) | C10—N3—C12—C13 | −5.2 (2) |
C9—N4—C14—C15 | 83.69 (16) | C14—C15—C16—C16ii | 179.71 (14) |
C11—N4—C14—C15 | −92.97 (15) | C1—N2—C6—C7 | 95.37 (16) |
C11—N4—C9—N3 | −0.59 (14) | C3—N2—C6—C7 | −77.73 (17) |
C14—N4—C9—N3 | −177.68 (11) | C8—C7—C6—N2 | −172.50 (12) |
C11—N4—C9—S2 | 179.67 (10) | C1—N2—C3—C2 | 0.89 (16) |
C14—N4—C9—S2 | 2.58 (19) | C6—N2—C3—C2 | 174.87 (13) |
C10—N3—C9—N4 | 0.39 (14) | N2—C3—C2—N1 | −0.64 (16) |
C12—N3—C9—N4 | −178.64 (12) | C1—N1—C2—C3 | 0.18 (15) |
C10—N3—C9—S2 | −179.88 (10) | C4—N1—C2—C3 | −178.10 (13) |
C12—N3—C9—S2 | 1.09 (19) | C1—N1—C4—C5 | −179.54 (14) |
C6—C7—C8—C8i | −179.90 (15) | C2—N1—C4—C5 | −1.5 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) −x, −y+1, −z+1. |
Cg1 and Cg2 are the centroids of the N1/N2/C1–C3 and N3/N4/C9–C11 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8B···Cg2iii | 0.99 | 2.75 | 3.628 (2) | 148 |
C15—H15B···Cg1ii | 0.99 | 2.76 | 3.589 (2) | 142 |
Symmetry codes: (ii) −x, −y+1, −z+1; (iii) x, y, z+1. |
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