Crystal structure of benzimidazolium salicylate

Amudha, M.; Kumar, P.P.; Chakkaravarthi, G.

doi:10.1107/S2056989015017764

organic compounds

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ISSN: 2056-9890

Volume 71| Part 10| October 2015| Pages o794-o795

doi:10.1107/S2056989015017764

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Crystal structure of benzimidazolium salicylate

M. Amudha,^a,^b P. Praveen Kumar ^a ^* and G. Chakkaravarthi ^c ^*

^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

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 12 September 2015; accepted 22 September 2015; online 26 September 2015)

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

C₇H₇N₂⁺·C₇H₅O₃⁻
M_r = 256.26
Monoclinic, P 2₁ /c
a = 7.4776 (3) Å
b = 6.7002 (2) Å
c = 24.9017 (9) Å
β = 94.445 (2)°
V = 1243.86 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 295 K
0.34 × 0.30 × 0.25 mm

2.2. Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.967, T_max = 0.976
23125 measured reflections
4606 independent reflections
3020 reflections with I > 2σ(I)
R_int = 0.024

2.3. Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.142
S = 1.03
4606 reflections
176 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

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⋯Cg3^iv	0.93	2.81	3.5779 (15)	141
C10—H10⋯Cg3^v	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) $[-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) x+1, y, z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S2056989015017764/su5212sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015017764/su5212Isup2.hkl

Supporting information file. DOI: 10.1107/S2056989015017764/su5212Isup3.cml

checkCIF report

Structural commentary top

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.

Synthesis and crystallization top

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 saturated solution was filtered and allowed to evaporate slowly at room temperature. Colourless block-shaped crystals of the title compound were obtained within seven days.

Refinement top

Crystal data, data collection and structure refinement 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 U_iso(H) = 1.5U_eq(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 U_iso(H) = 1.2U_eq(N,C).

Related literature top

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).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: 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).

Figures top

	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.

1H-Benzimidazol-3-ium 2-hydroxybenzoate top

Crystal data top

C₇H₇N₂⁺·C₇H₅O₃⁻	F(000) = 536
M_r = 256.26	D_x = 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

Data collection top

Bruker Kappa APEXII CCD diffractometer	4606 independent reflections
Radiation source: fine-focus sealed tube	3020 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ω and φ scan	θ_max = 39.4°, θ_min = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.967, T_max = 0.976	k = −11→9
23125 measured reflections	l = −35→35

Refinement top

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(F_o²) + (0.0618P)² + 0.2364P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max < 0.001
4606 reflections	Δρ_max = 0.35 e Å⁻³
176 parameters	Δρ_min = −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)

Crystal data top

C₇H₇N₂⁺·C₇H₅O₃⁻	V = 1243.86 (8) Å³
M_r = 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)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	4606 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3020 reflections with I > 2σ(I)
T_min = 0.967, T_max = 0.976	R_int = 0.024
23125 measured reflections

Refinement top

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	Δρ_max = 0.35 e Å⁻³
4606 reflections	Δρ_min = −0.26 e Å⁻³
176 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
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*

Atomic displacement parameters (Å²) top

	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)

Geometric parameters (Å, º) top

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)

Hydrogen-bond geometry (Å, º) top

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···Cg3^iv	0.93	2.81	3.5779 (15)	141
C10—H10···Cg3^v	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.

Hydrogen-bond geometry (Å, º) top

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···Cg3^iv	0.93	2.81	3.5779 (15)	141
C10—H10···Cg3^v	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.

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ISSN: 2056-9890

Volume 71| Part 10| October 2015| Pages o794-o795

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