organic compounds
of benzimidazolium salicylate
aDepartment of physics, Presidency College, Chennai 600 005, India, bDepartment of Physics, Aalim Muhammed Salegh College of Engineering, Chennai 600 055, India, and cDepartment of Physics, CPCL Polytechnic College, Chennai 600 068, India
*Correspondence e-mail: ppkpresidency@gmail.com, chakkaravarthi_2005@yahoo.com
In the anion of the title molecular salt, C7H7N2+·C7H5O3− (systematic name: 1H-benzimidazol-3-ium 2-hydroxybenzoate), there is an intramolecular O—H⋯O hydrogen bond that generates an S(6) ring motif. The CO2 group makes a dihedral angle of 5.33 (15)° with its attached ring. In the crystal, the dihedral angle between the benzimidazolium ring and the anion benzene ring is 75.88 (5)°. Two cations bridge two anions via two pairs of N—H⋯O hydrogen bonds, enclosing an R44(16) ring motif, forming a four-membered centrosymmetric arrangement. These units are linked via C—H⋯O hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked by C—H⋯π and π–π interactions [inter-centroid distances = 3.4156 (7) and 3.8196 (8) Å], forming a three-dimensional structure.
Keywords: crystal structure; benzimidazolium; salicylate; hydrogen bonding.
CCDC reference: 1426331
1. Related literature
For biological applications of benzimidazole derivatives, see: Narasimhan et al. (2012). For related structures, see: Ennajih et al. (2010); Haque et al. (2012); Mani et al. (2015).
2. Experimental
2.1. Crystal data
|
2.3. Refinement
|
Data collection: APEX2 (Bruker, 2004); cell SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 and PLATON.
Supporting information
CCDC reference: 1426331
10.1107/S2056989015017764/su5212sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015017764/su5212Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015017764/su5212Isup3.cml
Benzimidazoles and their derivatives have diverse biological and clinical applications (Narasimhan et al., 2012).
The molecular structure of the title salt is illustrated in Fig. 1. The geometric parameters are comparable with those reported for similar structures (Ennajih et al., 2010; Haque et al., 2012; Mani et al., 2015). The molecular structure of the anion is stabilized by an intramolecular O—H···O hydrogen bond which generates an S(6) ring motif (Table 1 and Fig. 1).
In the crystal, the dihedral angle between the nine-membered benzimidazolium ring (C8—C13/N2/C14/N1) and the anion benzene ring (C1—C6) is 75.88 (5)°. Two cations bridge two anions via two pairs of N—H···O hydrogen bonds, enclosing an R44(16) ring motif, forming a four-membered centrosymmetric arrangement (Table 1 and Fig. 2). These units are linked via C—H···O hydrogen bonds forming chains along the b axis direction. The chains are linked by C—H···π (Table 1) and π···π interactions [Cg1···Cg1i = 3.4156 (7) Å; Cg1···Cg2ii = 3.8196 (8) Å; Cg1 and Cg2 are the centroids of rings (N1/C8/C13/N2/C14) and (C8—C13), respectively; symmetry codes: (i) x+2, y+2, -z; (ii) -x+3, -y+2, -z], forming a three-dimensional structure.
Benzimidazole (6 g) and salicylic acid (7.002 g) were dissolved in an equimolar ratio in methanol and stirred well for ca 6 h. The
was filtered and allowed to evaporate slowly at room temperature. Colourless block-shaped crystals of the title compound were obtained within seven days.Crystal data, data collection and structure
details are summarized in Table 2. The hydroxyl H atom was located in a difference Fourier map and refined with a distance restraint: O—H = 0.82 (1) Å with Uiso(H) = 1.5Ueq(O). The NH and C-bound H atoms were positioned geometrically and refined using a riding model: N—H = 0.86 Å, C—H = 0.93 Å with Uiso(H) = 1.2Ueq(N,C).Data collection: APEX2 (Bruker, 2004); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).Fig. 1. The molecular structure of the title salt, with atom labelling. The displacement ellipsoids are drawn at the 30% probability level. | |
Fig. 2. The crystal packing of the title molecular salt, viewed along the b axis. The N—H···O and C—H···O hydrogen bonds are shown as dashed lines (see Table 1). H atoms not involved in these interactions have been omitted for clarity. |
C7H7N2+·C7H5O3− | F(000) = 536 |
Mr = 256.26 | Dx = 1.368 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 8207 reflections |
a = 7.4776 (3) Å | θ = 2.7–31.0° |
b = 6.7002 (2) Å | µ = 0.10 mm−1 |
c = 24.9017 (9) Å | T = 295 K |
β = 94.445 (2)° | Block, colourless |
V = 1243.86 (8) Å3 | 0.34 × 0.30 × 0.25 mm |
Z = 4 |
Bruker Kappa APEXII CCD diffractometer | 4606 independent reflections |
Radiation source: fine-focus sealed tube | 3020 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
ω and φ scan | θmax = 39.4°, θmin = 2.7° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −10→10 |
Tmin = 0.967, Tmax = 0.976 | k = −11→9 |
23125 measured reflections | l = −35→35 |
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)] = 0.048 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.142 | w = 1/[σ2(Fo2) + (0.0618P)2 + 0.2364P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max < 0.001 |
4606 reflections | Δρmax = 0.35 e Å−3 |
176 parameters | Δρmin = −0.26 e Å−3 |
1 restraint | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.025 (3) |
C7H7N2+·C7H5O3− | V = 1243.86 (8) Å3 |
Mr = 256.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.4776 (3) Å | µ = 0.10 mm−1 |
b = 6.7002 (2) Å | T = 295 K |
c = 24.9017 (9) Å | 0.34 × 0.30 × 0.25 mm |
β = 94.445 (2)° |
Bruker Kappa APEXII CCD diffractometer | 4606 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 3020 reflections with I > 2σ(I) |
Tmin = 0.967, Tmax = 0.976 | Rint = 0.024 |
23125 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 1 restraint |
wR(F2) = 0.142 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.35 e Å−3 |
4606 reflections | Δρmin = −0.26 e Å−3 |
176 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 | 0.85922 (14) | 0.54826 (15) | 0.16407 (4) | 0.0321 (2) | |
C2 | 0.94451 (17) | 0.73153 (18) | 0.17277 (5) | 0.0414 (3) | |
H2 | 1.0347 | 0.7692 | 0.1511 | 0.050* | |
C3 | 0.8971 (2) | 0.8581 (2) | 0.21304 (5) | 0.0499 (3) | |
H3 | 0.9554 | 0.9798 | 0.2187 | 0.060* | |
C4 | 0.76260 (19) | 0.8026 (2) | 0.24480 (5) | 0.0503 (3) | |
H4 | 0.7296 | 0.8882 | 0.2717 | 0.060* | |
C5 | 0.67701 (18) | 0.6234 (2) | 0.23729 (5) | 0.0475 (3) | |
H5 | 0.5866 | 0.5878 | 0.2591 | 0.057* | |
C6 | 0.72508 (16) | 0.49396 (18) | 0.19710 (4) | 0.0391 (3) | |
C7 | 0.91104 (17) | 0.41505 (16) | 0.12000 (4) | 0.0375 (2) | |
C8 | 1.27512 (15) | 1.05724 (17) | 0.05515 (5) | 0.0381 (2) | |
C9 | 1.3448 (2) | 1.0252 (2) | 0.10764 (6) | 0.0562 (4) | |
H9 | 1.3355 | 1.1203 | 0.1345 | 0.067* | |
C10 | 1.4287 (2) | 0.8448 (3) | 0.11783 (7) | 0.0697 (5) | |
H10 | 1.4781 | 0.8180 | 0.1525 | 0.084* | |
C11 | 1.4420 (2) | 0.7016 (3) | 0.07804 (8) | 0.0659 (4) | |
H11 | 1.4981 | 0.5810 | 0.0870 | 0.079* | |
C12 | 1.37525 (18) | 0.7325 (2) | 0.02618 (6) | 0.0516 (3) | |
H12 | 1.3854 | 0.6367 | −0.0004 | 0.062* | |
C13 | 1.29132 (15) | 0.91474 (16) | 0.01517 (5) | 0.0371 (2) | |
C14 | 1.14314 (16) | 1.17020 (18) | −0.02020 (5) | 0.0409 (3) | |
H14 | 1.0797 | 1.2524 | −0.0450 | 0.049* | |
N1 | 1.18155 (14) | 1.21523 (14) | 0.03109 (4) | 0.0398 (2) | |
H1A | 1.1532 | 1.3239 | 0.0467 | 0.048* | |
N2 | 1.20728 (13) | 0.99240 (14) | −0.03137 (4) | 0.0400 (2) | |
H2A | 1.1981 | 0.9351 | −0.0624 | 0.048* | |
O1 | 1.02203 (14) | 0.47695 (13) | 0.08885 (4) | 0.0521 (3) | |
O2 | 0.83774 (17) | 0.24546 (14) | 0.11610 (4) | 0.0613 (3) | |
O3 | 0.63621 (17) | 0.31901 (17) | 0.19135 (4) | 0.0653 (3) | |
H3A | 0.680 (3) | 0.261 (3) | 0.1658 (7) | 0.098* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0371 (5) | 0.0327 (5) | 0.0266 (4) | 0.0025 (4) | 0.0035 (4) | −0.0024 (4) |
C2 | 0.0442 (6) | 0.0390 (6) | 0.0411 (6) | −0.0041 (5) | 0.0050 (5) | −0.0034 (4) |
C3 | 0.0594 (8) | 0.0395 (6) | 0.0497 (7) | −0.0019 (6) | −0.0034 (6) | −0.0137 (5) |
C4 | 0.0556 (7) | 0.0559 (8) | 0.0389 (6) | 0.0139 (6) | 0.0004 (5) | −0.0169 (5) |
C5 | 0.0454 (6) | 0.0626 (8) | 0.0357 (6) | 0.0047 (6) | 0.0106 (5) | −0.0078 (5) |
C6 | 0.0413 (6) | 0.0431 (6) | 0.0334 (5) | −0.0024 (5) | 0.0065 (4) | −0.0031 (4) |
C7 | 0.0508 (6) | 0.0334 (5) | 0.0290 (5) | 0.0041 (4) | 0.0074 (4) | −0.0012 (4) |
C8 | 0.0342 (5) | 0.0409 (6) | 0.0400 (6) | −0.0039 (4) | 0.0077 (4) | −0.0050 (4) |
C9 | 0.0551 (8) | 0.0698 (9) | 0.0426 (7) | −0.0019 (7) | −0.0021 (6) | −0.0076 (6) |
C10 | 0.0627 (9) | 0.0871 (12) | 0.0566 (9) | 0.0073 (9) | −0.0127 (7) | 0.0111 (8) |
C11 | 0.0541 (8) | 0.0583 (9) | 0.0838 (11) | 0.0114 (7) | −0.0049 (8) | 0.0125 (8) |
C12 | 0.0431 (7) | 0.0421 (6) | 0.0701 (9) | 0.0045 (5) | 0.0083 (6) | −0.0051 (6) |
C13 | 0.0321 (5) | 0.0367 (5) | 0.0433 (6) | −0.0031 (4) | 0.0089 (4) | −0.0040 (4) |
C14 | 0.0436 (6) | 0.0393 (6) | 0.0409 (6) | −0.0013 (5) | 0.0113 (5) | 0.0021 (4) |
N1 | 0.0439 (5) | 0.0342 (5) | 0.0426 (5) | −0.0009 (4) | 0.0119 (4) | −0.0064 (4) |
N2 | 0.0454 (5) | 0.0404 (5) | 0.0354 (5) | −0.0036 (4) | 0.0100 (4) | −0.0066 (4) |
O1 | 0.0708 (6) | 0.0415 (5) | 0.0480 (5) | 0.0047 (4) | 0.0301 (4) | −0.0018 (4) |
O2 | 0.0956 (8) | 0.0428 (5) | 0.0487 (5) | −0.0176 (5) | 0.0264 (5) | −0.0168 (4) |
O3 | 0.0751 (7) | 0.0598 (6) | 0.0656 (7) | −0.0275 (5) | 0.0340 (5) | −0.0142 (5) |
C1—C2 | 1.3929 (16) | C8—C13 | 1.3913 (16) |
C1—C6 | 1.3939 (15) | C9—C10 | 1.376 (2) |
C1—C7 | 1.4889 (14) | C9—H9 | 0.9300 |
C2—C3 | 1.3803 (17) | C10—C11 | 1.388 (3) |
C2—H2 | 0.9300 | C10—H10 | 0.9300 |
C3—C4 | 1.378 (2) | C11—C12 | 1.364 (2) |
C3—H3 | 0.9300 | C11—H11 | 0.9300 |
C4—C5 | 1.367 (2) | C12—C13 | 1.3902 (17) |
C4—H4 | 0.9300 | C12—H12 | 0.9300 |
C5—C6 | 1.3922 (16) | C13—N2 | 1.3769 (15) |
C5—H5 | 0.9300 | C14—N2 | 1.3219 (15) |
C6—O3 | 1.3496 (15) | C14—N1 | 1.3220 (15) |
C7—O1 | 1.2499 (14) | C14—H14 | 0.9300 |
C7—O2 | 1.2620 (14) | N1—H1A | 0.8600 |
C8—N1 | 1.3798 (15) | N2—H2A | 0.8600 |
C8—C9 | 1.3861 (18) | O3—H3A | 0.834 (9) |
C2—C1—C6 | 118.68 (10) | C10—C9—H9 | 121.9 |
C2—C1—C7 | 120.07 (10) | C8—C9—H9 | 121.9 |
C6—C1—C7 | 121.25 (10) | C9—C10—C11 | 122.17 (14) |
C3—C2—C1 | 120.96 (12) | C9—C10—H10 | 118.9 |
C3—C2—H2 | 119.5 | C11—C10—H10 | 118.9 |
C1—C2—H2 | 119.5 | C12—C11—C10 | 121.97 (14) |
C4—C3—C2 | 119.41 (12) | C12—C11—H11 | 119.0 |
C4—C3—H3 | 120.3 | C10—C11—H11 | 119.0 |
C2—C3—H3 | 120.3 | C11—C12—C13 | 116.52 (13) |
C5—C4—C3 | 120.90 (11) | C11—C12—H12 | 121.7 |
C5—C4—H4 | 119.5 | C13—C12—H12 | 121.7 |
C3—C4—H4 | 119.5 | N2—C13—C12 | 131.86 (11) |
C4—C5—C6 | 120.08 (12) | N2—C13—C8 | 106.47 (10) |
C4—C5—H5 | 120.0 | C12—C13—C8 | 121.64 (12) |
C6—C5—H5 | 120.0 | N2—C14—N1 | 110.72 (11) |
O3—C6—C5 | 117.70 (11) | N2—C14—H14 | 124.6 |
O3—C6—C1 | 122.34 (10) | N1—C14—H14 | 124.6 |
C5—C6—C1 | 119.96 (11) | C14—N1—C8 | 108.01 (10) |
O1—C7—O2 | 123.80 (10) | C14—N1—H1A | 126.0 |
O1—C7—C1 | 118.80 (10) | C8—N1—H1A | 126.0 |
O2—C7—C1 | 117.40 (10) | C14—N2—C13 | 108.22 (10) |
N1—C8—C9 | 132.02 (11) | C14—N2—H2A | 125.9 |
N1—C8—C13 | 106.57 (10) | C13—N2—H2A | 125.9 |
C9—C8—C13 | 121.41 (12) | C6—O3—H3A | 105.2 (16) |
C10—C9—C8 | 116.28 (14) | ||
C6—C1—C2—C3 | −0.37 (17) | C13—C8—C9—C10 | −0.6 (2) |
C7—C1—C2—C3 | 179.30 (11) | C8—C9—C10—C11 | −0.5 (2) |
C1—C2—C3—C4 | −0.42 (19) | C9—C10—C11—C12 | 1.1 (3) |
C2—C3—C4—C5 | 0.6 (2) | C10—C11—C12—C13 | −0.6 (2) |
C3—C4—C5—C6 | −0.1 (2) | C11—C12—C13—N2 | −178.38 (13) |
C4—C5—C6—O3 | −179.93 (12) | C11—C12—C13—C8 | −0.51 (19) |
C4—C5—C6—C1 | −0.75 (19) | N1—C8—C13—N2 | 0.10 (12) |
C2—C1—C6—O3 | −179.91 (12) | C9—C8—C13—N2 | 179.49 (11) |
C7—C1—C6—O3 | 0.42 (18) | N1—C8—C13—C12 | −178.25 (11) |
C2—C1—C6—C5 | 0.96 (17) | C9—C8—C13—C12 | 1.14 (18) |
C7—C1—C6—C5 | −178.71 (11) | N2—C14—N1—C8 | −0.50 (13) |
C2—C1—C7—O1 | −5.18 (17) | C9—C8—N1—C14 | −179.06 (14) |
C6—C1—C7—O1 | 174.49 (11) | C13—C8—N1—C14 | 0.23 (13) |
C2—C1—C7—O2 | 175.54 (12) | N1—C14—N2—C13 | 0.56 (13) |
C6—C1—C7—O2 | −4.79 (17) | C12—C13—N2—C14 | 177.72 (13) |
N1—C8—C9—C10 | 178.60 (14) | C8—C13—N2—C14 | −0.40 (12) |
Cg3 is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O2 | 0.83 (1) | 1.78 (1) | 2.5425 (14) | 152 (2) |
N1—H1A···O1i | 0.86 | 1.81 | 2.6139 (13) | 155 |
N2—H2A···O2ii | 0.86 | 1.81 | 2.6448 (13) | 164 |
C14—H14···O1iii | 0.93 | 2.22 | 3.1161 (16) | 161 |
C3—H3···Cg3iv | 0.93 | 2.81 | 3.5779 (15) | 141 |
C10—H10···Cg3v | 0.93 | 2.88 | 3.6302 (17) | 139 |
Symmetry codes: (i) x, y+1, z; (ii) −x+2, −y+1, −z; (iii) −x+2, −y+2, −z; (iv) −x+2, y+1/2, −z+1/2; (v) x+1, y, z. |
Cg3 is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O2 | 0.834 (9) | 1.775 (13) | 2.5425 (14) | 152 (2) |
N1—H1A···O1i | 0.86 | 1.81 | 2.6139 (13) | 155 |
N2—H2A···O2ii | 0.86 | 1.81 | 2.6448 (13) | 164 |
C14—H14···O1iii | 0.93 | 2.22 | 3.1161 (16) | 161 |
C3—H3···Cg3iv | 0.93 | 2.81 | 3.5779 (15) | 141 |
C10—H10···Cg3v | 0.93 | 2.88 | 3.6302 (17) | 139 |
Symmetry codes: (i) x, y+1, z; (ii) −x+2, −y+1, −z; (iii) −x+2, −y+2, −z; (iv) −x+2, y+1/2, −z+1/2; (v) x+1, y, z. |
Acknowledgements
The authors wish to acknowledge the SAIF, IIT Madras, for the data collection.
References
Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Ennajih, H., Bouhfid, R., Zouihri, H., Essassi, E. M. & Ng, S. W. (2010). Acta Cryst. E66, o455. Web of Science CSD CrossRef IUCr Journals Google Scholar
Haque, R. A., Iqbal, M. A., Budagumpi, S., Hemamalini, M. & Fun, H.-K. (2012). Acta Cryst. E68, o573. CSD CrossRef IUCr Journals Google Scholar
Mani, A., Kumar, P. P. & Chakkaravarthi, G. (2015). Acta Cryst. E71, o643–o644. CSD CrossRef IUCr Journals Google Scholar
Narasimhan, B., Sharma, D. & Kumar, P. (2012). Med. Chem. Res. 21, 269–283. Web of Science CrossRef CAS Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals 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.