organic compounds
2-Ethylimidazolium terephthalate
aOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, People's Republic of China
*Correspondence e-mail: zhurunqiang@163.com
The 5H9N2+·C8H5O4−, consists of one protonated 2-ethylimidazolium cation and two half terephthalate anions. The anions and cations are linked through N—H⋯O hydrogen bonds while the anions are associated via O—H⋯O interactions, resulting in a layered structure. The ethyl group of the cation is disordered over twosites of occupancies 0.812 (14) and 0.188 (14). The hydroxy H atoms of the anions are equally disordered over two symmetry-related sites.
of the title compound, CRelated literature
The title compound was synthesized as part of our search for ferroelectric materials. For general background to ferroelectric organic frameworks, see: Fu et al. (2009); Ye et al. (2006); Zhang et al. (2008, 2010). For related structures, see: Tian (2007); Qu (2007).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2005); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536811038578/vm2120sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811038578/vm2120Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811038578/vm2120Isup3.cml
A mixture of 2-ethyl imidazole (2.4 g, 25 mmol), terephthalic acid (25 mmol) in water was stirred for several days at ambient temperature. Colourless block crystals were obtained.
All H atoms were positioned geometrically and refined using a riding model, with C–H distances of 0.93–0.97Å, O—H = 0.82
Å and N–H = 0.86 Å. All H atoms were refined with isotropic displacement parameters set to 1.2 times the Ueq of the parent atom, except for methyl and hydroxyl H atoms where it was set to 1.5 times the Ueq of the parent atom.
With reference to the compounds 2(C4H7N2)+.C8H4O42-.2(C4H6N2).4(H2O) (Qu, 2007) and 2(C3H5N)+.C8H4O42- (Tian, 2007), we synthesized the title compound to find ferroelectric material by dielectric measurements of compound as a function of temperature (Fu et al., 2009; Ye et al., 2006; Zhang et al., 2008; Zhang et al., 2010). In the range from 190 K to near its melting point (m.p.>423 K), no dielectric anomaly was observed.
In the
(Fig. 1) determined at 293 K, we observe short O···O distances in the range 2.448 (3)–2.450 (3) Å between the interacting carboxylic acid groups. The H atoms attached to O2 and O4 are disordered. The O···O distances are much shorter than the N···O distances which are 2.714 (3) and 2.738 Å (Table 1).The title compound was synthesized as part of our search for ferroelectric materials. For general background to ferroelectric organic frameworks, see: Fu et al. (2009); Ye et al. (2006); Zhang et al. (2008, 2010). For related structures, see: Tian (2007); Qu (2007).
Data collection: CrystalClear (Rigaku, 2005); cell
CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C5H9N2+·C8H5O4− | Z = 2 |
Mr = 262.26 | F(000) = 276 |
Triclinic, P1 | Dx = 1.348 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.4587 (13) Å | Cell parameters from 2933 reflections |
b = 7.0719 (14) Å | θ = 2.2–27.5° |
c = 14.688 (3) Å | µ = 0.10 mm−1 |
α = 78.60 (3)° | T = 293 K |
β = 78.77 (3)° | Block, colourless |
γ = 89.50 (3)° | 0.30 × 0.25 × 0.20 mm |
V = 644.7 (2) Å3 |
Rigaku SCXmini diffractometer | 2933 independent reflections |
Radiation source: fine-focus sealed tube | 2197 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.034 |
CCD Profile fitting scans | θmax = 27.5°, θmin = 3.0° |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | h = −8→8 |
Tmin = 0.970, Tmax = 0.980 | k = −9→9 |
6568 measured reflections | l = −18→19 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.060 | H-atom parameters constrained |
wR(F2) = 0.171 | w = 1/[σ2(Fo2) + (0.0708P)2 + 0.3515P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
2933 reflections | Δρmax = 0.29 e Å−3 |
194 parameters | Δρmin = −0.24 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.084 (10) |
C5H9N2+·C8H5O4− | γ = 89.50 (3)° |
Mr = 262.26 | V = 644.7 (2) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.4587 (13) Å | Mo Kα radiation |
b = 7.0719 (14) Å | µ = 0.10 mm−1 |
c = 14.688 (3) Å | T = 293 K |
α = 78.60 (3)° | 0.30 × 0.25 × 0.20 mm |
β = 78.77 (3)° |
Rigaku SCXmini diffractometer | 2933 independent reflections |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | 2197 reflections with I > 2σ(I) |
Tmin = 0.970, Tmax = 0.980 | Rint = 0.034 |
6568 measured reflections |
R[F2 > 2σ(F2)] = 0.060 | 0 restraints |
wR(F2) = 0.171 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.29 e Å−3 |
2933 reflections | Δρmin = −0.24 e Å−3 |
194 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 | Occ. (<1) | |
C1 | 0.7347 (7) | 0.9795 (9) | 0.2520 (3) | 0.0599 (13) | 0.808 (14) |
H1A | 0.6126 | 1.0576 | 0.2508 | 0.090* | 0.808 (14) |
H1B | 0.8455 | 1.0340 | 0.1999 | 0.090* | 0.808 (14) |
H1C | 0.7815 | 0.9756 | 0.3105 | 0.090* | 0.808 (14) |
C2 | 0.6784 (7) | 0.7753 (6) | 0.2440 (3) | 0.0508 (13) | 0.808 (14) |
H2A | 0.5645 | 0.7218 | 0.2961 | 0.061* | 0.808 (14) |
H2B | 0.6286 | 0.7802 | 0.1854 | 0.061* | 0.808 (14) |
C1' | 0.544 (5) | 0.812 (5) | 0.2476 (14) | 0.113 (11) | 0.192 (14) |
H1'A | 0.4549 | 0.9202 | 0.2539 | 0.170* | 0.192 (14) |
H1'B | 0.4893 | 0.7036 | 0.2965 | 0.170* | 0.192 (14) |
H1'C | 0.5486 | 0.7805 | 0.1867 | 0.170* | 0.192 (14) |
C2' | 0.759 (4) | 0.863 (4) | 0.2564 (12) | 0.068 (7) | 0.192 (14) |
H2'A | 0.7635 | 0.8948 | 0.3174 | 0.082* | 0.192 (14) |
H2'B | 0.8256 | 0.9671 | 0.2057 | 0.082* | 0.192 (14) |
C3 | 0.8617 (4) | 0.6470 (4) | 0.24548 (17) | 0.0477 (6) | |
C4 | 1.1731 (4) | 0.5205 (4) | 0.21494 (18) | 0.0477 (6) | |
H4 | 1.3152 | 0.5068 | 0.1905 | 0.057* | |
C5 | 1.0399 (4) | 0.3850 (4) | 0.27270 (18) | 0.0511 (6) | |
H5 | 1.0717 | 0.2583 | 0.2960 | 0.061* | |
C6 | 0.3529 (3) | 0.2725 (3) | 0.46010 (16) | 0.0378 (5) | |
C7 | 0.1695 (3) | 0.1309 (3) | 0.48246 (14) | 0.0327 (5) | |
C8 | 0.1917 (3) | −0.0380 (3) | 0.44744 (16) | 0.0392 (5) | |
H8 | 0.3206 | −0.0636 | 0.4118 | 0.047* | |
C9 | 0.0230 (4) | −0.1691 (3) | 0.46529 (16) | 0.0398 (5) | |
H9 | 0.0394 | −0.2826 | 0.4421 | 0.048* | |
C10 | 0.2463 (3) | 0.1473 (3) | 1.03616 (15) | 0.0356 (5) | |
C11 | 0.3795 (3) | 0.3302 (3) | 1.01537 (14) | 0.0303 (5) | |
C12 | 0.3127 (3) | 0.5022 (3) | 0.96744 (15) | 0.0336 (5) | |
H12 | 0.1871 | 0.5039 | 0.9453 | 0.040* | |
C13 | 0.4326 (3) | 0.6717 (3) | 0.95247 (15) | 0.0336 (5) | |
H13 | 0.3867 | 0.7866 | 0.9208 | 0.040* | |
N1 | 0.8498 (3) | 0.4672 (3) | 0.29095 (14) | 0.0505 (6) | |
H1D | 0.7379 | 0.4096 | 0.3271 | 0.061* | |
N2 | 1.0596 (3) | 0.6826 (3) | 0.19901 (14) | 0.0472 (5) | |
H2C | 1.1087 | 0.7915 | 0.1642 | 0.057* | |
O1 | 0.2779 (3) | 0.0121 (2) | 1.09758 (13) | 0.0556 (5) | |
O2 | 0.1042 (3) | 0.1504 (2) | 0.98639 (14) | 0.0573 (5) | |
H2 | 0.0476 | 0.0429 | 0.9968 | 0.086* | 0.50 |
O3 | 0.4954 (3) | 0.2675 (3) | 0.39276 (13) | 0.0595 (6) | |
O4 | 0.3451 (3) | 0.3907 (3) | 0.51614 (14) | 0.0648 (6) | |
H4A | 0.4374 | 0.4752 | 0.4941 | 0.097* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.082 (3) | 0.044 (3) | 0.053 (2) | 0.011 (2) | −0.0086 (18) | −0.0121 (18) |
C2 | 0.043 (3) | 0.055 (2) | 0.050 (2) | −0.0016 (17) | 0.0018 (16) | −0.0096 (16) |
C1' | 0.09 (2) | 0.21 (3) | 0.051 (11) | 0.055 (18) | −0.021 (11) | −0.040 (14) |
C2' | 0.088 (14) | 0.072 (19) | 0.044 (8) | −0.025 (13) | −0.010 (8) | −0.012 (9) |
C3 | 0.0503 (14) | 0.0481 (13) | 0.0376 (12) | −0.0027 (11) | 0.0033 (10) | −0.0032 (10) |
C4 | 0.0409 (13) | 0.0482 (14) | 0.0496 (14) | −0.0041 (10) | −0.0002 (11) | −0.0078 (11) |
C5 | 0.0583 (16) | 0.0408 (13) | 0.0500 (14) | −0.0033 (11) | −0.0084 (12) | −0.0010 (11) |
C6 | 0.0347 (11) | 0.0369 (11) | 0.0402 (12) | −0.0150 (9) | −0.0043 (9) | −0.0063 (9) |
C7 | 0.0297 (10) | 0.0330 (10) | 0.0338 (10) | −0.0121 (8) | −0.0050 (8) | −0.0037 (8) |
C8 | 0.0307 (11) | 0.0415 (12) | 0.0442 (12) | −0.0085 (9) | 0.0012 (9) | −0.0138 (9) |
C9 | 0.0386 (12) | 0.0334 (11) | 0.0471 (13) | −0.0105 (9) | −0.0011 (10) | −0.0143 (9) |
C10 | 0.0339 (11) | 0.0308 (10) | 0.0400 (11) | −0.0143 (8) | −0.0007 (9) | −0.0073 (9) |
C11 | 0.0296 (10) | 0.0272 (9) | 0.0319 (10) | −0.0110 (8) | −0.0002 (8) | −0.0062 (8) |
C12 | 0.0284 (10) | 0.0341 (10) | 0.0394 (11) | −0.0086 (8) | −0.0093 (8) | −0.0069 (8) |
C13 | 0.0337 (11) | 0.0264 (9) | 0.0392 (11) | −0.0069 (8) | −0.0082 (9) | −0.0016 (8) |
N1 | 0.0473 (12) | 0.0518 (12) | 0.0420 (11) | −0.0162 (9) | 0.0033 (9) | 0.0040 (9) |
N2 | 0.0486 (12) | 0.0369 (10) | 0.0459 (11) | −0.0128 (9) | 0.0060 (9) | 0.0019 (8) |
O1 | 0.0599 (11) | 0.0355 (9) | 0.0645 (12) | −0.0245 (8) | −0.0137 (9) | 0.0091 (8) |
O2 | 0.0574 (11) | 0.0468 (10) | 0.0699 (12) | −0.0323 (9) | −0.0257 (10) | −0.0024 (9) |
O3 | 0.0464 (10) | 0.0627 (12) | 0.0623 (12) | −0.0298 (9) | 0.0151 (9) | −0.0197 (9) |
O4 | 0.0571 (12) | 0.0692 (13) | 0.0679 (13) | −0.0384 (10) | 0.0113 (9) | −0.0345 (10) |
C1—C2 | 1.525 (7) | C6—O4 | 1.278 (3) |
C1—H1A | 0.9600 | C6—C7 | 1.501 (3) |
C1—H1B | 0.9600 | C7—C9i | 1.383 (3) |
C1—H1C | 0.9600 | C7—C8 | 1.387 (3) |
C2—C3 | 1.486 (5) | C8—C9 | 1.388 (3) |
C2—H2A | 0.9700 | C8—H8 | 0.9300 |
C2—H2B | 0.9700 | C9—C7i | 1.383 (3) |
C1'—C2' | 1.47 (4) | C9—H9 | 0.9300 |
C1'—H1'A | 0.9600 | C10—O1 | 1.224 (3) |
C1'—H1'B | 0.9600 | C10—O2 | 1.277 (3) |
C1'—H1'C | 0.9600 | C10—C11 | 1.506 (3) |
C2'—C3 | 1.69 (3) | C11—C13ii | 1.384 (3) |
C2'—H2'A | 0.9700 | C11—C12 | 1.390 (3) |
C2'—H2'B | 0.9700 | C12—C13 | 1.389 (3) |
C3—N1 | 1.310 (3) | C12—H12 | 0.9300 |
C3—N2 | 1.327 (3) | C13—C11ii | 1.384 (3) |
C4—C5 | 1.337 (3) | C13—H13 | 0.9300 |
C4—N2 | 1.361 (3) | N1—H1D | 0.8600 |
C4—H4 | 0.9300 | N2—H2C | 0.8600 |
C5—N1 | 1.356 (4) | O2—H2 | 0.8200 |
C5—H5 | 0.9300 | O4—H4A | 0.8200 |
C6—O3 | 1.219 (3) | ||
C2—C1—H1A | 109.5 | C4—C5—H5 | 126.5 |
C2—C1—H1B | 109.5 | N1—C5—H5 | 126.5 |
H1A—C1—H1B | 109.5 | O3—C6—O4 | 125.1 (2) |
C2—C1—H1C | 109.5 | O3—C6—C7 | 119.7 (2) |
H1A—C1—H1C | 109.5 | O4—C6—C7 | 115.20 (19) |
H1B—C1—H1C | 109.5 | C9i—C7—C8 | 119.54 (18) |
C3—C2—C1 | 112.1 (4) | C9i—C7—C6 | 121.07 (19) |
C3—C2—H2A | 109.2 | C8—C7—C6 | 119.35 (19) |
C1—C2—H2A | 109.2 | C7—C8—C9 | 120.4 (2) |
C3—C2—H2B | 109.2 | C7—C8—H8 | 119.8 |
C1—C2—H2B | 109.2 | C9—C8—H8 | 119.8 |
H2A—C2—H2B | 107.9 | C7i—C9—C8 | 120.0 (2) |
C2'—C1'—H1'A | 109.5 | C7i—C9—H9 | 120.0 |
C2'—C1'—H1'B | 109.5 | C8—C9—H9 | 120.0 |
H1'A—C1'—H1'B | 109.5 | O1—C10—O2 | 125.55 (19) |
C2'—C1'—H1'C | 109.5 | O1—C10—C11 | 119.7 (2) |
H1'A—C1'—H1'C | 109.5 | O2—C10—C11 | 114.72 (19) |
H1'B—C1'—H1'C | 109.5 | C13ii—C11—C12 | 119.61 (18) |
C1'—C2'—C3 | 96 (2) | C13ii—C11—C10 | 119.44 (18) |
C1'—C2'—H2'A | 112.6 | C12—C11—C10 | 120.91 (18) |
C3—C2'—H2'A | 112.6 | C13—C12—C11 | 120.29 (19) |
C1'—C2'—H2'B | 112.6 | C13—C12—H12 | 119.9 |
C3—C2'—H2'B | 112.6 | C11—C12—H12 | 119.9 |
H2'A—C2'—H2'B | 110.1 | C11ii—C13—C12 | 120.10 (19) |
N1—C3—N2 | 107.0 (2) | C11ii—C13—H13 | 120.0 |
N1—C3—C2 | 124.2 (3) | C12—C13—H13 | 120.0 |
N2—C3—C2 | 128.7 (2) | C3—N1—C5 | 110.0 (2) |
N1—C3—C2' | 140.7 (6) | C3—N1—H1D | 125.0 |
N2—C3—C2' | 106.2 (7) | C5—N1—H1D | 125.0 |
C2—C3—C2' | 31.6 (7) | C3—N2—C4 | 109.5 (2) |
C5—C4—N2 | 106.4 (2) | C3—N2—H2C | 125.2 |
C5—C4—H4 | 126.8 | C4—N2—H2C | 125.2 |
N2—C4—H4 | 126.8 | C10—O2—H2 | 109.5 |
C4—C5—N1 | 107.0 (2) | C6—O4—H4A | 109.5 |
Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4A···O4iii | 0.82 | 1.67 | 2.452 (3) | 160 |
O2—H2···O2iv | 0.82 | 1.64 | 2.450 (3) | 170 |
N2—H2C···O1v | 0.86 | 1.90 | 2.739 (3) | 166 |
N1—H1D···O3 | 0.86 | 1.86 | 2.713 (3) | 173 |
Symmetry codes: (iii) −x+1, −y+1, −z+1; (iv) −x, −y, −z+2; (v) x+1, y+1, z−1. |
Experimental details
Crystal data | |
Chemical formula | C5H9N2+·C8H5O4− |
Mr | 262.26 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.4587 (13), 7.0719 (14), 14.688 (3) |
α, β, γ (°) | 78.60 (3), 78.77 (3), 89.50 (3) |
V (Å3) | 644.7 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.30 × 0.25 × 0.20 |
Data collection | |
Diffractometer | Rigaku SCXmini |
Absorption correction | Multi-scan (CrystalClear; Rigaku, 2005) |
Tmin, Tmax | 0.970, 0.980 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6568, 2933, 2197 |
Rint | 0.034 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.060, 0.171, 1.07 |
No. of reflections | 2933 |
No. of parameters | 194 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.29, −0.24 |
Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005).
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4A···O4i | 0.82 | 1.67 | 2.452 (3) | 159.5 |
O2—H2···O2ii | 0.82 | 1.64 | 2.450 (3) | 169.5 |
N2—H2C···O1iii | 0.86 | 1.90 | 2.739 (3) | 166.1 |
N1—H1D···O3 | 0.86 | 1.86 | 2.713 (3) | 172.6 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y, −z+2; (iii) x+1, y+1, z−1. |
Acknowledgements
This work was supported by Southeast University.
References
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With reference to the compounds 2(C4H7N2)+.C8H4O42-.2(C4H6N2).4(H2O) (Qu, 2007) and 2(C3H5N)+.C8H4O42- (Tian, 2007), we synthesized the title compound to find ferroelectric material by dielectric measurements of compound as a function of temperature (Fu et al., 2009; Ye et al., 2006; Zhang et al., 2008; Zhang et al., 2010). In the range from 190 K to near its melting point (m.p.>423 K), no dielectric anomaly was observed.
In the crystal structure (Fig. 1) determined at 293 K, we observe short O···O distances in the range 2.448 (3)–2.450 (3) Å between the interacting carboxylic acid groups. The H atoms attached to O2 and O4 are disordered. The O···O distances are much shorter than the N···O distances which are 2.714 (3) and 2.738 Å (Table 1).