organic compounds
1-(2-Carboxyethyl)-3-(carboxylatomethyl)-2-ethylbenzimidazol-1-ium monohydrate
aKey Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: zhangnwnu@126.com
In the title compound, C14H16N2O4·H2O, three substituent groups are located on the same side of the benzimidazole ring plane. In the crystal, O—H⋯O hydrogen bonds and π–π stacking between parallel imidazole rings [centroid–centroid distance = 3.858 (4) Å] link the molecules into a three-dimensional supramolecular structure.
Related literature
For general background to supramolecular coordination complexes, see: Chakrabarty et al. (2011); Cook et al. (2012); Wang et al. (2009, 2010). For related structures, see: Wei et al. (2012); Chen & Huang (2006); Wu et al. (2012).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); 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/S1600536813006855/xu5687sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813006855/xu5687Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813006855/xu5687Isup3.cml
1-(2-Acetoxy)-3-(3-propionyloxy)-2-ethyl-3H-benzimidazolium salt (0.2 mmol, 0.0552 g) was dissolved in distilled water. Colorless block crystals separated after several weeks.
Water H atoms were located in a difference Fourier map and refined isotropically. Other H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 and O—H = 0.82 Å, Uiso(H) = 1.5Ueq(C,O).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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).C14H16N2O4·H2O | Z = 2 |
Mr = 294.30 | F(000) = 312 |
Triclinic, P1 | Dx = 1.403 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.286 (7) Å | Cell parameters from 1681 reflections |
b = 9.041 (8) Å | θ = 2.4–26.1° |
c = 10.629 (9) Å | µ = 0.11 mm−1 |
α = 69.905 (7)° | T = 296 K |
β = 69.096 (7)° | Block, colourless |
γ = 79.082 (8)° | 0.26 × 0.23 × 0.22 mm |
V = 696.6 (10) Å3 |
Bruker APEXII CCD diffractometer | 2551 independent reflections |
Radiation source: fine-focus sealed tube | 1888 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
ϕ and ω scans | θmax = 25.5°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −10→9 |
Tmin = 0.973, Tmax = 0.977 | k = −10→10 |
5039 measured reflections | l = −12→12 |
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)] = 0.042 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.102 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0456P)2 + 0.0692P] where P = (Fo2 + 2Fc2)/3 |
2551 reflections | (Δ/σ)max < 0.001 |
200 parameters | Δρmax = 0.18 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C14H16N2O4·H2O | γ = 79.082 (8)° |
Mr = 294.30 | V = 696.6 (10) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.286 (7) Å | Mo Kα radiation |
b = 9.041 (8) Å | µ = 0.11 mm−1 |
c = 10.629 (9) Å | T = 296 K |
α = 69.905 (7)° | 0.26 × 0.23 × 0.22 mm |
β = 69.096 (7)° |
Bruker APEXII CCD diffractometer | 2551 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 1888 reflections with I > 2σ(I) |
Tmin = 0.973, Tmax = 0.977 | Rint = 0.022 |
5039 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.102 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.18 e Å−3 |
2551 reflections | Δρmin = −0.23 e Å−3 |
200 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 | 0.2641 (2) | 1.08245 (19) | 0.06635 (18) | 0.0295 (4) | |
C2 | 0.2190 (2) | 1.1649 (2) | −0.05422 (18) | 0.0358 (4) | |
H2 | 0.2043 | 1.2747 | −0.0837 | 0.043* | |
C3 | 0.1973 (2) | 1.0757 (2) | −0.12773 (19) | 0.0420 (5) | |
H3 | 0.1676 | 1.1265 | −0.2096 | 0.050* | |
C4 | 0.2185 (3) | 0.9111 (2) | −0.0833 (2) | 0.0423 (5) | |
H4 | 0.2019 | 0.8555 | −0.1363 | 0.051* | |
C5 | 0.2629 (2) | 0.8285 (2) | 0.03621 (19) | 0.0388 (5) | |
H5 | 0.2767 | 0.7188 | 0.0657 | 0.047* | |
C6 | 0.2861 (2) | 0.91826 (19) | 0.11035 (17) | 0.0309 (4) | |
C7 | 0.3413 (2) | 1.0071 (2) | 0.26096 (19) | 0.0333 (4) | |
C8 | 0.3829 (3) | 1.0131 (2) | 0.3834 (2) | 0.0455 (5) | |
H8A | 0.4589 | 1.0970 | 0.3522 | 0.055* | |
H8B | 0.4449 | 0.9142 | 0.4195 | 0.055* | |
C9 | 0.2221 (3) | 1.0414 (3) | 0.5024 (2) | 0.0526 (6) | |
H9A | 0.1572 | 1.1366 | 0.4663 | 0.079* | |
H9B | 0.2565 | 1.0516 | 0.5760 | 0.079* | |
H9C | 0.1513 | 0.9539 | 0.5396 | 0.079* | |
C10 | 0.2867 (2) | 1.2987 (2) | 0.1588 (2) | 0.0375 (5) | |
H10A | 0.3267 | 1.3640 | 0.0613 | 0.045* | |
H10B | 0.3618 | 1.3096 | 0.2067 | 0.045* | |
C11 | 0.1029 (3) | 1.3575 (2) | 0.22808 (19) | 0.0371 (4) | |
C12 | 0.3833 (2) | 0.7124 (2) | 0.30663 (19) | 0.0417 (5) | |
H12A | 0.4830 | 0.7123 | 0.3342 | 0.050* | |
H12B | 0.4172 | 0.6495 | 0.2422 | 0.050* | |
C13 | 0.2397 (2) | 0.63694 (19) | 0.43592 (19) | 0.0370 (4) | |
H13A | 0.2173 | 0.6898 | 0.5066 | 0.044* | |
H13B | 0.1347 | 0.6500 | 0.4113 | 0.044* | |
C14 | 0.2846 (3) | 0.4640 (2) | 0.4969 (2) | 0.0388 (5) | |
N1 | 0.29992 (18) | 1.13350 (15) | 0.16246 (15) | 0.0312 (4) | |
N2 | 0.33392 (18) | 0.87598 (16) | 0.23231 (15) | 0.0334 (4) | |
O1 | 0.09505 (19) | 1.48021 (15) | 0.26178 (15) | 0.0534 (4) | |
O2 | −0.01868 (18) | 1.28600 (16) | 0.24520 (16) | 0.0548 (4) | |
O3 | 0.1787 (2) | 0.38995 (15) | 0.61738 (15) | 0.0562 (4) | |
H3A | 0.0996 | 0.4523 | 0.6453 | 0.084* | |
O4 | 0.41378 (18) | 0.39251 (15) | 0.43815 (15) | 0.0523 (4) | |
O5 | 0.3224 (3) | 0.5657 (2) | 0.8276 (2) | 0.0651 (5) | |
H1W | 0.405 (4) | 0.594 (3) | 0.734 (3) | 0.097 (10)* | |
H2W | 0.230 (4) | 0.614 (4) | 0.800 (3) | 0.114 (12)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0273 (10) | 0.0276 (9) | 0.0312 (9) | −0.0028 (7) | −0.0062 (7) | −0.0088 (7) |
C2 | 0.0375 (11) | 0.0312 (9) | 0.0334 (10) | −0.0035 (8) | −0.0093 (8) | −0.0047 (8) |
C3 | 0.0484 (13) | 0.0456 (11) | 0.0298 (10) | −0.0060 (9) | −0.0126 (9) | −0.0072 (8) |
C4 | 0.0490 (13) | 0.0449 (11) | 0.0365 (11) | −0.0089 (9) | −0.0086 (9) | −0.0187 (9) |
C5 | 0.0426 (11) | 0.0280 (9) | 0.0412 (11) | −0.0042 (8) | −0.0047 (9) | −0.0129 (8) |
C6 | 0.0280 (10) | 0.0293 (9) | 0.0294 (9) | −0.0021 (7) | −0.0054 (7) | −0.0055 (7) |
C7 | 0.0268 (10) | 0.0361 (10) | 0.0349 (10) | 0.0004 (7) | −0.0099 (8) | −0.0094 (8) |
C8 | 0.0450 (12) | 0.0533 (12) | 0.0434 (11) | −0.0027 (9) | −0.0218 (10) | −0.0133 (9) |
C9 | 0.0569 (14) | 0.0669 (14) | 0.0397 (11) | −0.0077 (11) | −0.0166 (10) | −0.0200 (10) |
C10 | 0.0400 (11) | 0.0311 (9) | 0.0450 (11) | −0.0064 (8) | −0.0130 (9) | −0.0141 (8) |
C11 | 0.0427 (12) | 0.0296 (10) | 0.0349 (10) | −0.0028 (9) | −0.0103 (9) | −0.0069 (8) |
C12 | 0.0397 (11) | 0.0323 (10) | 0.0416 (11) | 0.0075 (8) | −0.0123 (9) | −0.0030 (8) |
C13 | 0.0397 (11) | 0.0306 (10) | 0.0382 (10) | 0.0002 (8) | −0.0121 (9) | −0.0090 (8) |
C14 | 0.0432 (12) | 0.0324 (10) | 0.0389 (11) | 0.0001 (9) | −0.0140 (9) | −0.0091 (8) |
N1 | 0.0322 (8) | 0.0284 (8) | 0.0343 (8) | −0.0022 (6) | −0.0113 (7) | −0.0101 (6) |
N2 | 0.0350 (9) | 0.0286 (8) | 0.0322 (8) | 0.0015 (6) | −0.0116 (7) | −0.0050 (6) |
O1 | 0.0616 (10) | 0.0376 (8) | 0.0585 (9) | −0.0083 (7) | −0.0041 (7) | −0.0246 (7) |
O2 | 0.0385 (9) | 0.0531 (9) | 0.0754 (11) | −0.0040 (7) | −0.0103 (7) | −0.0303 (8) |
O3 | 0.0669 (11) | 0.0318 (7) | 0.0469 (8) | 0.0043 (7) | −0.0031 (8) | −0.0036 (6) |
O4 | 0.0472 (9) | 0.0376 (8) | 0.0580 (9) | 0.0093 (7) | −0.0098 (7) | −0.0111 (7) |
O5 | 0.0661 (12) | 0.0636 (11) | 0.0644 (12) | 0.0109 (9) | −0.0241 (11) | −0.0227 (9) |
C1—C2 | 1.385 (3) | C9—H9C | 0.9600 |
C1—N1 | 1.392 (2) | C10—N1 | 1.464 (2) |
C1—C6 | 1.392 (3) | C10—C11 | 1.518 (3) |
C2—C3 | 1.372 (3) | C10—H10A | 0.9700 |
C2—H2 | 0.9300 | C10—H10B | 0.9700 |
C3—C4 | 1.395 (3) | C11—O2 | 1.225 (2) |
C3—H3 | 0.9300 | C11—O1 | 1.262 (2) |
C4—C5 | 1.373 (3) | C12—N2 | 1.475 (2) |
C4—H4 | 0.9300 | C12—C13 | 1.505 (3) |
C5—C6 | 1.387 (3) | C12—H12A | 0.9700 |
C5—H5 | 0.9300 | C12—H12B | 0.9700 |
C6—N2 | 1.397 (2) | C13—C14 | 1.503 (3) |
C7—N2 | 1.338 (2) | C13—H13A | 0.9700 |
C7—N1 | 1.344 (2) | C13—H13B | 0.9700 |
C7—C8 | 1.481 (3) | C14—O4 | 1.221 (2) |
C8—C9 | 1.527 (3) | C14—O3 | 1.300 (2) |
C8—H8A | 0.9700 | O3—H3A | 0.8200 |
C8—H8B | 0.9700 | O5—H1W | 0.96 (3) |
C9—H9A | 0.9600 | O5—H2W | 0.90 (3) |
C9—H9B | 0.9600 | ||
C2—C1—N1 | 131.62 (16) | N1—C10—C11 | 112.57 (14) |
C2—C1—C6 | 121.81 (16) | N1—C10—H10A | 109.1 |
N1—C1—C6 | 106.55 (15) | C11—C10—H10A | 109.1 |
C3—C2—C1 | 116.25 (17) | N1—C10—H10B | 109.1 |
C3—C2—H2 | 121.9 | C11—C10—H10B | 109.1 |
C1—C2—H2 | 121.9 | H10A—C10—H10B | 107.8 |
C2—C3—C4 | 121.97 (18) | O2—C11—O1 | 127.11 (18) |
C2—C3—H3 | 119.0 | O2—C11—C10 | 119.49 (17) |
C4—C3—H3 | 119.0 | O1—C11—C10 | 113.39 (17) |
C5—C4—C3 | 122.09 (18) | N2—C12—C13 | 113.06 (15) |
C5—C4—H4 | 119.0 | N2—C12—H12A | 109.0 |
C3—C4—H4 | 119.0 | C13—C12—H12A | 109.0 |
C4—C5—C6 | 116.14 (17) | N2—C12—H12B | 109.0 |
C4—C5—H5 | 121.9 | C13—C12—H12B | 109.0 |
C6—C5—H5 | 121.9 | H12A—C12—H12B | 107.8 |
C5—C6—C1 | 121.74 (17) | C14—C13—C12 | 111.66 (16) |
C5—C6—N2 | 131.85 (16) | C14—C13—H13A | 109.3 |
C1—C6—N2 | 106.40 (15) | C12—C13—H13A | 109.3 |
N2—C7—N1 | 108.99 (16) | C14—C13—H13B | 109.3 |
N2—C7—C8 | 125.90 (16) | C12—C13—H13B | 109.3 |
N1—C7—C8 | 125.09 (17) | H13A—C13—H13B | 107.9 |
C7—C8—C9 | 112.83 (17) | O4—C14—O3 | 119.89 (17) |
C7—C8—H8A | 109.0 | O4—C14—C13 | 122.94 (17) |
C9—C8—H8A | 109.0 | O3—C14—C13 | 117.17 (17) |
C7—C8—H8B | 109.0 | C7—N1—C1 | 109.03 (15) |
C9—C8—H8B | 109.0 | C7—N1—C10 | 126.07 (16) |
H8A—C8—H8B | 107.8 | C1—N1—C10 | 124.85 (14) |
C8—C9—H9A | 109.5 | C7—N2—C6 | 109.03 (14) |
C8—C9—H9B | 109.5 | C7—N2—C12 | 126.86 (16) |
H9A—C9—H9B | 109.5 | C6—N2—C12 | 123.88 (15) |
C8—C9—H9C | 109.5 | C14—O3—H3A | 109.5 |
H9A—C9—H9C | 109.5 | H1W—O5—H2W | 95 (2) |
H9B—C9—H9C | 109.5 | ||
N1—C1—C2—C3 | 178.24 (17) | C8—C7—N1—C1 | −178.25 (16) |
C6—C1—C2—C3 | 0.0 (3) | N2—C7—N1—C10 | 177.63 (15) |
C1—C2—C3—C4 | 0.3 (3) | C8—C7—N1—C10 | −0.7 (3) |
C2—C3—C4—C5 | −0.3 (3) | C2—C1—N1—C7 | −178.66 (18) |
C3—C4—C5—C6 | −0.2 (3) | C6—C1—N1—C7 | −0.20 (18) |
C4—C5—C6—C1 | 0.5 (3) | C2—C1—N1—C10 | 3.8 (3) |
C4—C5—C6—N2 | −178.59 (18) | C6—C1—N1—C10 | −177.77 (15) |
C2—C1—C6—C5 | −0.4 (3) | C11—C10—N1—C7 | −94.1 (2) |
N1—C1—C6—C5 | −179.05 (15) | C11—C10—N1—C1 | 83.0 (2) |
C2—C1—C6—N2 | 178.87 (16) | N1—C7—N2—C6 | 0.06 (19) |
N1—C1—C6—N2 | 0.23 (17) | C8—C7—N2—C6 | 178.38 (16) |
N2—C7—C8—C9 | −100.2 (2) | N1—C7—N2—C12 | 174.64 (15) |
N1—C7—C8—C9 | 77.8 (2) | C8—C7—N2—C12 | −7.0 (3) |
N1—C10—C11—O2 | −19.1 (2) | C5—C6—N2—C7 | 178.99 (18) |
N1—C10—C11—O1 | 161.19 (15) | C1—C6—N2—C7 | −0.18 (19) |
N2—C12—C13—C14 | 171.70 (16) | C5—C6—N2—C12 | 4.2 (3) |
C12—C13—C14—O4 | −7.5 (3) | C1—C6—N2—C12 | −174.96 (15) |
C12—C13—C14—O3 | 172.71 (17) | C13—C12—N2—C7 | 85.2 (2) |
N2—C7—N1—C1 | 0.09 (19) | C13—C12—N2—C6 | −101.0 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O1i | 0.82 | 1.69 | 2.474 (2) | 160 |
O5—H1W···O4ii | 0.96 (3) | 1.89 (3) | 2.841 (3) | 168 (2) |
O5—H2W···O2i | 0.90 (3) | 1.96 (3) | 2.851 (3) | 176 (3) |
Symmetry codes: (i) −x, −y+2, −z+1; (ii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C14H16N2O4·H2O |
Mr | 294.30 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 296 |
a, b, c (Å) | 8.286 (7), 9.041 (8), 10.629 (9) |
α, β, γ (°) | 69.905 (7), 69.096 (7), 79.082 (8) |
V (Å3) | 696.6 (10) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.26 × 0.23 × 0.22 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.973, 0.977 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5039, 2551, 1888 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.102, 1.07 |
No. of reflections | 2551 |
No. of parameters | 200 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.18, −0.23 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O1i | 0.82 | 1.69 | 2.474 (2) | 159.6 |
O5—H1W···O4ii | 0.96 (3) | 1.89 (3) | 2.841 (3) | 168 (2) |
O5—H2W···O2i | 0.90 (3) | 1.96 (3) | 2.851 (3) | 176 (3) |
Symmetry codes: (i) −x, −y+2, −z+1; (ii) −x+1, −y+1, −z+1. |
Acknowledgements
This work was supported by the National Natural Science Foundation of China (Nos. 21064006, 21161018 and 21262032), the Program for Changjiang Scholars and Innovative Research Teams in Universities of the Ministry of Education of China (No. IRT1177), the Natural Science Foundation of Gansu Province (No. 1010RJZA018), the Youth Foundation of Gansu Province (No. 1208RJYA048) and NWNU-LKQN-11–32.
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Benzimidazole and its derivatives are strongly coordinating agents and form stable complexes with various metals, which find various application in supramolecular coordination complexes, catalytic systems and soft materials (Chakrabarty et al., 2011; Cook et al., 2012; Wang et al., 2009; Wei et al., 2012). Meanwhile, the coordination chemistry of dicarboxylates has gained great attention for a variety of reasons, such as good conformation freedom, various coordination modes and so on (Wang et al., 2010; Wu et al., 2012). Herein we report the crystal structure of 1-(2-acetoxy)-3-(3-propionyloxy)-2-ethyl-3H-benzimidazolium salt and the molecular structure is shown in Fig 1. In the imidazolium ring, the bond lenghs range from 1.338 (2) to 1.397 (2) Å, in good agreement with the presence of conjugated double bonds and indicating a zwitterionic structure (Chen & Huang, 2006). In the U-shaped molecule, the two carboxyl group run almost perpendicular to the benzimidazolium plane in the same orientation. The N1—C10—C11 and N2—C12—C13 angles are 112.57 (14) and 113.06 (15)°, respectively. A dimer is formed by benzimidazolium salt connected to neighboring molecule through O3—H3A ···O1 hydrogen bonds (Fig 2). In addition, the dimer makes full use of two water molecules as bridging molecules to form various O—H···O hydrogen bonds to generate the wide hydrogen-bond ribbon (Fig 3). Obviously, water molecules, as a kind of linking unit, play an important role in constructing this structure. The distance between the donor and acceptor of the hydrogen bond is in the range of 2.474 (2)–2.851 (3) Å. π-π stacking is observed between parallel imidazole rings of adjacent molecules [1-x, 2-y, -z], the centroids distance being 3.858 (4) Å.