organic compounds
1-{2-[(4-Hydroxy-3-methoxybenzylidene)amino]ethyl}-3-methylimidazolium hexafluorophosphate
aDepartment of Chemistry, Jinan University, Guangzhou 510632, People's Republic of China
*Correspondence e-mail: tlyq@jnu.edu.cn
In the title Schiff base salt, C14H18N3O2+·PF6−, the dihedral angle between the planes of the aromatic and imidazole rings is 24.84 (8)°. The molecular structure exhibits an intramolecular O—H⋯O hydrogen bond, which generates an S(5) ring motif. In the the cations and anions are connected via O—H⋯N and O—H⋯F hydrogen bonds, resulting in a trifurcated interaction for the phenolic H atom.
Related literature
For bond-length data, see: Allen et al. (1987). For the synthesis of see: Pradeep (2005); Butcher et al. (2005). For information on ionic liquids and their applications, see: Xiao et al. (2004); Welton (1999); Wilkes (2002).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2002); cell SAINT (Bruker, 2002); data reduction: SAINT; 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/S160053680901928X/su2112sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053680901928X/su2112Isup2.hkl
A mixture of the ionic liquid 1-(2-aminoethyl)-3-methylimidazolium hexafluorophosphate (4 mmol) and 4-hydroxy-3- methoxybenzaldehyde (3 mmol) was stirred for 4 h at rt, under solvent-free conditions. After completion of the reaction, ethanol (30 ml) was added to the reaction mixture. The solid product was then filtered off and washed with cold ethanol. The crude product was purified by recrystallization in ethanol/ethyl acetate(3:1 v/v). Single crystals, suitable for X-ray
were obtained by slow evaporation of an ethyl acetate solution of the complex at rt.All the H-atoms could be located in difference Fourier maps and were refined as riding atoms: O—H = 0.84 Å, with Uiso(H) = 1.5 Ueq(O); C—H = 0.95–0.98 Å with Uiso(H) = 1.2 Ueq(C).
Data collection: SMART (Bruker, 2002); cell
SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); 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).Fig. 1. The molecular structure of the title compound, showing the atom numbering Scheme. Displacement ellipsoids are drawn at the 50% probability level. |
C14H18N3O2+·PF6− | F(000) = 832 |
Mr = 405.28 | Dx = 1.591 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 4600 reflections |
a = 7.5285 (10) Å | θ = 2.3–27.1° |
b = 12.6850 (16) Å | µ = 0.24 mm−1 |
c = 17.827 (2) Å | T = 173 K |
β = 96.245 (2)° | Block, colorless |
V = 1692.3 (4) Å3 | 0.48 × 0.43 × 0.38 mm |
Z = 4 |
Bruker SMART CCD area-detector diffractometer | 3635 independent reflections |
Radiation source: fine-focus sealed tube | 2904 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.019 |
ϕ and ω scans | θmax = 27.1°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −7→9 |
Tmin = 0.894, Tmax = 0.914 | k = −16→13 |
8519 measured reflections | l = −22→22 |
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)] = 0.034 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0489P)2 + 0.5604P] where P = (Fo2 + 2Fc2)/3 |
3635 reflections | (Δ/σ)max = 0.001 |
238 parameters | Δρmax = 0.26 e Å−3 |
0 restraints | Δρmin = −0.29 e Å−3 |
C14H18N3O2+·PF6− | V = 1692.3 (4) Å3 |
Mr = 405.28 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 7.5285 (10) Å | µ = 0.24 mm−1 |
b = 12.6850 (16) Å | T = 173 K |
c = 17.827 (2) Å | 0.48 × 0.43 × 0.38 mm |
β = 96.245 (2)° |
Bruker SMART CCD area-detector diffractometer | 3635 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2904 reflections with I > 2σ(I) |
Tmin = 0.894, Tmax = 0.914 | Rint = 0.019 |
8519 measured reflections |
R[F2 > 2σ(F2)] = 0.034 | 0 restraints |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.26 e Å−3 |
3635 reflections | Δρmin = −0.29 e Å−3 |
238 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 | ||
C1 | 0.4931 (2) | 0.59395 (12) | 0.15334 (9) | 0.0254 (3) | |
C2 | 0.5820 (2) | 0.59443 (12) | 0.22669 (9) | 0.0245 (3) | |
H2 | 0.5929 | 0.6582 | 0.2548 | 0.029* | |
C3 | 0.6536 (2) | 0.50227 (12) | 0.25801 (9) | 0.0246 (3) | |
C4 | 0.6351 (2) | 0.40751 (12) | 0.21695 (9) | 0.0277 (3) | |
C5 | 0.5435 (2) | 0.40639 (13) | 0.14557 (9) | 0.0302 (4) | |
H5 | 0.5282 | 0.3421 | 0.1182 | 0.036* | |
C6 | 0.4735 (2) | 0.49990 (12) | 0.11374 (9) | 0.0283 (3) | |
H6 | 0.4118 | 0.4992 | 0.0644 | 0.034* | |
C7 | 0.7471 (2) | 0.58042 (14) | 0.37782 (10) | 0.0363 (4) | |
H7A | 0.8078 | 0.6402 | 0.3568 | 0.054* | |
H7B | 0.8098 | 0.5613 | 0.4270 | 0.054* | |
H7C | 0.6236 | 0.6001 | 0.3839 | 0.054* | |
C8 | 0.4221 (2) | 0.69108 (13) | 0.11667 (9) | 0.0264 (3) | |
H8 | 0.3633 | 0.6859 | 0.0669 | 0.032* | |
C9 | 0.3561 (2) | 0.86914 (13) | 0.10164 (9) | 0.0286 (3) | |
H9A | 0.2947 | 0.8417 | 0.0537 | 0.034* | |
H9B | 0.4520 | 0.9176 | 0.0894 | 0.034* | |
C10 | 0.2231 (2) | 0.92900 (14) | 0.14407 (10) | 0.0324 (4) | |
H10A | 0.1602 | 0.9819 | 0.1100 | 0.039* | |
H10B | 0.1329 | 0.8792 | 0.1598 | 0.039* | |
C11 | 0.3670 (2) | 0.93695 (13) | 0.27651 (9) | 0.0281 (3) | |
H11 | 0.3487 | 0.8652 | 0.2889 | 0.034* | |
C12 | 0.4516 (2) | 1.10234 (13) | 0.28397 (10) | 0.0330 (4) | |
H12 | 0.5030 | 1.1667 | 0.3031 | 0.040* | |
C13 | 0.3652 (2) | 1.08660 (13) | 0.21491 (10) | 0.0336 (4) | |
H13 | 0.3445 | 1.1377 | 0.1760 | 0.040* | |
C14 | 0.5274 (3) | 0.98980 (16) | 0.39957 (10) | 0.0420 (4) | |
H14A | 0.4489 | 1.0207 | 0.4341 | 0.063* | |
H14B | 0.6457 | 1.0226 | 0.4081 | 0.063* | |
H14C | 0.5383 | 0.9138 | 0.4088 | 0.063* | |
F1 | −0.02389 (14) | 0.28060 (9) | −0.01415 (7) | 0.0477 (3) | |
F2 | 0.17917 (17) | 0.21418 (9) | −0.08507 (6) | 0.0500 (3) | |
F3 | 0.07180 (16) | 0.11320 (8) | 0.00376 (7) | 0.0503 (3) | |
F4 | 0.35699 (15) | 0.17051 (10) | 0.02179 (7) | 0.0536 (3) | |
F5 | 0.15258 (16) | 0.23765 (10) | 0.09197 (6) | 0.0485 (3) | |
F6 | 0.26139 (15) | 0.33750 (8) | 0.00272 (6) | 0.0474 (3) | |
N1 | 0.43423 (18) | 0.78152 (10) | 0.14719 (7) | 0.0288 (3) | |
N2 | 0.31202 (17) | 0.98250 (10) | 0.21108 (8) | 0.0279 (3) | |
N3 | 0.45170 (18) | 1.00816 (11) | 0.32170 (8) | 0.0291 (3) | |
O1 | 0.74720 (16) | 0.49223 (9) | 0.32760 (6) | 0.0325 (3) | |
O2 | 0.70614 (18) | 0.31595 (9) | 0.24688 (7) | 0.0409 (3) | |
H2A | 0.7684 | 0.3288 | 0.2879 | 0.061* | |
P1 | 0.16710 (6) | 0.22501 (3) | 0.00298 (2) | 0.02858 (13) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0204 (7) | 0.0258 (8) | 0.0301 (8) | −0.0006 (6) | 0.0031 (6) | 0.0002 (6) |
C2 | 0.0254 (7) | 0.0209 (7) | 0.0274 (8) | −0.0027 (6) | 0.0036 (6) | −0.0027 (6) |
C3 | 0.0240 (7) | 0.0249 (8) | 0.0249 (8) | −0.0043 (6) | 0.0027 (6) | 0.0006 (6) |
C4 | 0.0300 (8) | 0.0210 (7) | 0.0316 (9) | −0.0009 (6) | 0.0011 (6) | 0.0015 (6) |
C5 | 0.0332 (9) | 0.0234 (8) | 0.0334 (9) | −0.0014 (6) | 0.0006 (7) | −0.0063 (7) |
C6 | 0.0265 (8) | 0.0299 (8) | 0.0272 (8) | −0.0018 (6) | −0.0024 (6) | −0.0023 (7) |
C7 | 0.0422 (10) | 0.0370 (10) | 0.0285 (9) | 0.0013 (8) | −0.0018 (7) | −0.0083 (7) |
C8 | 0.0234 (7) | 0.0305 (8) | 0.0248 (8) | 0.0001 (6) | 0.0005 (6) | 0.0000 (6) |
C9 | 0.0331 (8) | 0.0259 (8) | 0.0255 (8) | 0.0028 (6) | −0.0024 (6) | 0.0015 (6) |
C10 | 0.0286 (8) | 0.0317 (9) | 0.0351 (9) | 0.0054 (7) | −0.0052 (7) | −0.0021 (7) |
C11 | 0.0296 (8) | 0.0258 (8) | 0.0291 (8) | −0.0015 (6) | 0.0043 (6) | −0.0003 (7) |
C12 | 0.0326 (9) | 0.0247 (8) | 0.0429 (10) | −0.0022 (7) | 0.0101 (7) | −0.0038 (7) |
C13 | 0.0357 (9) | 0.0234 (8) | 0.0427 (10) | 0.0041 (7) | 0.0087 (7) | 0.0029 (7) |
C14 | 0.0475 (11) | 0.0507 (12) | 0.0272 (9) | −0.0067 (9) | 0.0018 (8) | −0.0051 (8) |
F1 | 0.0338 (6) | 0.0458 (7) | 0.0599 (7) | 0.0069 (5) | −0.0110 (5) | −0.0037 (5) |
F2 | 0.0641 (8) | 0.0555 (7) | 0.0306 (6) | −0.0080 (6) | 0.0059 (5) | −0.0050 (5) |
F3 | 0.0612 (8) | 0.0312 (6) | 0.0591 (8) | −0.0099 (5) | 0.0093 (6) | 0.0020 (5) |
F4 | 0.0404 (6) | 0.0603 (8) | 0.0592 (7) | 0.0186 (6) | 0.0011 (5) | 0.0041 (6) |
F5 | 0.0596 (7) | 0.0563 (7) | 0.0293 (6) | 0.0083 (6) | 0.0042 (5) | 0.0001 (5) |
F6 | 0.0505 (7) | 0.0366 (6) | 0.0513 (7) | −0.0149 (5) | −0.0111 (5) | 0.0023 (5) |
N1 | 0.0337 (7) | 0.0258 (7) | 0.0259 (7) | 0.0046 (6) | −0.0006 (5) | 0.0016 (6) |
N2 | 0.0263 (7) | 0.0256 (7) | 0.0317 (7) | 0.0044 (5) | 0.0033 (5) | −0.0004 (6) |
N3 | 0.0293 (7) | 0.0290 (7) | 0.0297 (7) | −0.0026 (6) | 0.0064 (5) | −0.0031 (6) |
O1 | 0.0436 (7) | 0.0250 (6) | 0.0267 (6) | 0.0000 (5) | −0.0057 (5) | −0.0007 (5) |
O2 | 0.0582 (9) | 0.0214 (6) | 0.0388 (7) | 0.0025 (6) | −0.0149 (6) | −0.0013 (5) |
P1 | 0.0299 (2) | 0.0267 (2) | 0.0283 (2) | 0.00017 (17) | −0.00086 (16) | 0.00051 (17) |
C1—C6 | 1.386 (2) | C10—N2 | 1.470 (2) |
C1—C2 | 1.403 (2) | C10—H10A | 0.9900 |
C1—C8 | 1.468 (2) | C10—H10B | 0.9900 |
C2—C3 | 1.380 (2) | C11—N3 | 1.327 (2) |
C2—H2 | 0.9500 | C11—N2 | 1.327 (2) |
C3—O1 | 1.3644 (18) | C11—H11 | 0.9500 |
C3—C4 | 1.406 (2) | C12—C13 | 1.343 (3) |
C4—O2 | 1.3629 (19) | C12—N3 | 1.371 (2) |
C4—C5 | 1.380 (2) | C12—H12 | 0.9500 |
C5—C6 | 1.393 (2) | C13—N2 | 1.379 (2) |
C5—H5 | 0.9500 | C13—H13 | 0.9500 |
C6—H6 | 0.9500 | C14—N3 | 1.461 (2) |
C7—O1 | 1.433 (2) | C14—H14A | 0.9800 |
C7—H7A | 0.9800 | C14—H14B | 0.9800 |
C7—H7B | 0.9800 | C14—H14C | 0.9800 |
C7—H7C | 0.9800 | F1—P1 | 1.6008 (11) |
C8—N1 | 1.269 (2) | F2—P1 | 1.5880 (11) |
C8—H8 | 0.9500 | F3—P1 | 1.5902 (11) |
C9—N1 | 1.4618 (19) | F4—P1 | 1.5905 (11) |
C9—C10 | 1.521 (2) | F5—P1 | 1.6101 (11) |
C9—H9A | 0.9900 | F6—P1 | 1.5941 (11) |
C9—H9B | 0.9900 | O2—H2A | 0.8400 |
C6—C1—C2 | 119.47 (14) | N3—C11—N2 | 108.71 (15) |
C6—C1—C8 | 118.84 (14) | N3—C11—H11 | 125.6 |
C2—C1—C8 | 121.68 (14) | N2—C11—H11 | 125.6 |
C3—C2—C1 | 119.96 (14) | C13—C12—N3 | 107.13 (15) |
C3—C2—H2 | 120.0 | C13—C12—H12 | 126.4 |
C1—C2—H2 | 120.0 | N3—C12—H12 | 126.4 |
O1—C3—C2 | 125.97 (14) | C12—C13—N2 | 107.25 (15) |
O1—C3—C4 | 113.93 (13) | C12—C13—H13 | 126.4 |
C2—C3—C4 | 120.09 (14) | N2—C13—H13 | 126.4 |
O2—C4—C5 | 119.19 (14) | N3—C14—H14A | 109.5 |
O2—C4—C3 | 120.81 (14) | N3—C14—H14B | 109.5 |
C5—C4—C3 | 120.00 (14) | H14A—C14—H14B | 109.5 |
C4—C5—C6 | 119.71 (15) | N3—C14—H14C | 109.5 |
C4—C5—H5 | 120.1 | H14A—C14—H14C | 109.5 |
C6—C5—H5 | 120.1 | H14B—C14—H14C | 109.5 |
C1—C6—C5 | 120.73 (14) | C8—N1—C9 | 116.33 (14) |
C1—C6—H6 | 119.6 | C11—N2—C13 | 108.20 (14) |
C5—C6—H6 | 119.6 | C11—N2—C10 | 125.74 (14) |
O1—C7—H7A | 109.5 | C13—N2—C10 | 125.87 (14) |
O1—C7—H7B | 109.5 | C11—N3—C12 | 108.71 (14) |
H7A—C7—H7B | 109.5 | C11—N3—C14 | 125.50 (15) |
O1—C7—H7C | 109.5 | C12—N3—C14 | 125.77 (14) |
H7A—C7—H7C | 109.5 | C3—O1—C7 | 117.38 (12) |
H7B—C7—H7C | 109.5 | C4—O2—H2A | 109.5 |
N1—C8—C1 | 124.21 (14) | F2—P1—F3 | 90.34 (6) |
N1—C8—H8 | 117.9 | F2—P1—F4 | 91.38 (7) |
C1—C8—H8 | 117.9 | F3—P1—F4 | 90.37 (7) |
N1—C9—C10 | 110.50 (14) | F2—P1—F6 | 90.07 (6) |
N1—C9—H9A | 109.6 | F3—P1—F6 | 179.46 (7) |
C10—C9—H9A | 109.6 | F4—P1—F6 | 89.96 (7) |
N1—C9—H9B | 109.6 | F2—P1—F1 | 89.80 (7) |
C10—C9—H9B | 109.6 | F3—P1—F1 | 89.88 (6) |
H9A—C9—H9B | 108.1 | F4—P1—F1 | 178.80 (7) |
N2—C10—C9 | 111.62 (13) | F6—P1—F1 | 89.78 (6) |
N2—C10—H10A | 109.3 | F2—P1—F5 | 179.03 (7) |
C9—C10—H10A | 109.3 | F3—P1—F5 | 90.06 (7) |
N2—C10—H10B | 109.3 | F4—P1—F5 | 89.50 (6) |
C9—C10—H10B | 109.3 | F6—P1—F5 | 89.52 (6) |
H10A—C10—H10B | 108.0 | F1—P1—F5 | 89.32 (6) |
C6—C1—C2—C3 | 1.8 (2) | N3—C12—C13—N2 | 0.31 (19) |
C8—C1—C2—C3 | −177.20 (14) | C1—C8—N1—C9 | 179.71 (14) |
C1—C2—C3—O1 | 178.08 (14) | C10—C9—N1—C8 | 125.58 (16) |
C1—C2—C3—C4 | −1.0 (2) | N3—C11—N2—C13 | 0.40 (18) |
O1—C3—C4—O2 | 0.3 (2) | N3—C11—N2—C10 | 175.73 (14) |
C2—C3—C4—O2 | 179.53 (15) | C12—C13—N2—C11 | −0.44 (19) |
O1—C3—C4—C5 | −179.91 (15) | C12—C13—N2—C10 | −175.77 (15) |
C2—C3—C4—C5 | −0.7 (2) | C9—C10—N2—C11 | −78.2 (2) |
O2—C4—C5—C6 | −178.65 (15) | C9—C10—N2—C13 | 96.36 (19) |
C3—C4—C5—C6 | 1.6 (3) | N2—C11—N3—C12 | −0.20 (19) |
C2—C1—C6—C5 | −1.0 (2) | N2—C11—N3—C14 | 178.01 (15) |
C8—C1—C6—C5 | 178.10 (15) | C13—C12—N3—C11 | −0.08 (19) |
C4—C5—C6—C1 | −0.8 (3) | C13—C12—N3—C14 | −178.29 (16) |
C6—C1—C8—N1 | −179.14 (16) | C2—C3—O1—C7 | 10.9 (2) |
C2—C1—C8—N1 | −0.1 (2) | C4—C3—O1—C7 | −169.95 (15) |
N1—C9—C10—N2 | 66.34 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1 | 0.84 | 2.20 | 2.6589 (16) | 114 |
O2—H2A···N1i | 0.84 | 2.48 | 3.1584 (18) | 139 |
O2—H2A···F2ii | 0.84 | 2.49 | 3.0487 (18) | 125 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) x+1/2, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H18N3O2+·PF6− |
Mr | 405.28 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 173 |
a, b, c (Å) | 7.5285 (10), 12.6850 (16), 17.827 (2) |
β (°) | 96.245 (2) |
V (Å3) | 1692.3 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.24 |
Crystal size (mm) | 0.48 × 0.43 × 0.38 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.894, 0.914 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8519, 3635, 2904 |
Rint | 0.019 |
(sin θ/λ)max (Å−1) | 0.640 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.034, 0.099, 1.07 |
No. of reflections | 3635 |
No. of parameters | 238 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.26, −0.29 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1 | 0.84 | 2.20 | 2.6589 (16) | 114 |
O2—H2A···N1i | 0.84 | 2.48 | 3.1584 (18) | 139 |
O2—H2A···F2ii | 0.84 | 2.49 | 3.0487 (18) | 125 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) x+1/2, −y+1/2, z+1/2. |
Acknowledgements
The authors are grateful to the National Natural Science Foundation of China (grant No. 20672046) and the Guangdong Natural Science Foundation (grant No. 8151063201000016) for financial support.
References
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Ionic liquids have aroused considerable interest over the past decade due to their wide variety of properties such as high thermal and chemical stability, no measurable vapor pressure, non-flammability, friction reduction, and high loading capacity, etc (Xiao et al., 2004; Welton, 1999; Wilkes, 2002). Schiff base compounds are one of the most prevalent mixed-donor ligands in the field of coordination chemistry (Pradeep, 2005; Butcher et al., 2005). Our interest in this field of research lead us to synthesis the title compound, and we report here on the crystal structure of this novel ionic liquid-supported Schiff base.
The title compound is a Schiff base derived from the condensation of 4-hydroxy-3-methoxybenzaldehyde with the ionic liquid 1-(2-aminoethyl)-3- methylimidazolium hexafluorophosphate, under solvent-free conditions. The molecular structure of the title compound is illustrated in Fig. 1. The asymmetric unit comprises one cation and one PF6 anion. The bond lengths (Allen et al., 1987) and angles are generally within normal ranges. The aromatic ring and imidazole ring are not coplanar but are inclined to one another by an angle of 24.84 (8)°. In the molecular structure, the intramolocular O2—H2A···O1 hydrogen bonds form a pseudo five membered ring [S(5) motif], thus locking the molecular conformation and eliminating any flexibility (Table 1).
In the crystal structure symmetry related cations and anions are connected via O-H···N and O-H···F hydrogen bonds (Table 1).