2-Amino­benzimidazolium hydrogen sulfate

You, W.; Fan, Y.; Qian, H.-F.; Yao, C.; Huang, W.

doi:10.1107/S1600536808041706

organic compounds

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ISSN: 2056-9890

Volume 65| Part 1| January 2009| Page o115

doi:10.1107/S1600536808041706

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2-Aminobenzimidazolium hydrogen sulfate

Wei You,^a Ying Fan,^a Hui-Fen Qian,^a ^* Cheng Yao ^a and Wei Huang ^b ‡

^aCollege of Sciences, Nanjing University of Technology, Nanjing, 210009, People's Republic of China, and ^bState Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, People's Republic of China
^*Correspondence e-mail: whuang@nju.edu.cn

(Received 3 December 2008; accepted 9 December 2008; online 13 December 2008)

In the title salt, C₇H₈N₃⁺·HSO₄⁻, the benzimdazole ring system is planar [mean deviation 0.0086 (1) Å]. In the crystal, N—H⋯O and O—H⋯O hydrogen-bond interactions give rise to a layer motif.

Related literature

For related compounds, see: El-Medania et al. (2003 ); Yeşilel et al. (2008 ).

Experimental

Crystal data

C₇H₈N₃⁺·HSO₄⁻
M_r = 231.23
Monoclinic, P 2₁ /c
a = 10.855 (6) Å
b = 13.049 (7) Å
c = 7.082 (4) Å
β = 99.025 (7)°
V = 990.7 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.33 mm⁻¹
T = 291 (2) K
0.16 × 0.12 × 0.10 mm

Data collection

Bruker SMART diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.950, T_max = 0.968
5083 measured reflections
1841 independent reflections
1408 reflections with I > 2σ(I)
R_int = 0.057

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.103
S = 0.96
1841 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O4ⁱ	0.86	2.00	2.848 (3)	167
O1—H1B⋯O2ⁱⁱ	0.82	1.80	2.619 (2)	176
N2—H2A⋯O3	0.86	1.94	2.795 (2)	177
N3—H3A⋯O3ⁱ	0.86	2.09	2.899 (3)	157
N3—H3B⋯O2	0.86	2.17	2.987 (2)	158
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808041706/ng2522sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808041706/ng2522Isup2.hkl

checkCIF report

Comment top

Several ion-pair adducts of 2-aminobenzimidazole with different organic acids such as picric acid (El-Medania et al., 2003) and squaric acid (YeŞilel et al., 2008) have been reported. Herein, we present a hydrogen sulfate of 2-aminobenzimidazole.

The atom-numbering scheme of the title compound is shown in Fig. 1, while selected bond distances and bond angles are given in Table 1. The benzimidazole skeleton of the title compound is planar and the proton is delocalized within the imidazole ring although it is added to one of the nitrogen atoms. With regard to the hydrogen sulfate anion, the hydrogen atom is added to the O1 atom of SO₄ group due to the obviously longer O1–S1 bond length. In the crystal packing, typical π-π stacking can be found between neighbouring aromatic rings with the centroid-to-centroid separation of 3.452 (2) Å. Furthermore, N—H···O and O—H···O hydrogen bonding interactions are found between adjacent molecules to form a three-dimensional network (Fig. 2).

Related literature top

For related compounds, see: El-Medania et al. (2003); YeŞilel et al. (2008).

Experimental top

The treatment of 2-aminobenzimidazole dissolved in methanol with an excess of hydrochloric acid yields the title compound. Single crystal suitable for X-ray diffraction measurement was obtained after 3 days' slow evaporation of the mother liquid at room temperature in air. Anal. Calcd. For C~7~H~9Ñ~3Õ~4~S: C, 36.36; H, 3.92; O, 27.68%. Found: C, 36.17; H, 4.03; N, 27.74%. Main FT—IR absorptions (KBr pellets, cm^-1): 3385 (s), 3194 (m), 1687 (s), 1476 (m), 1286 (m), 1206(s), 1175 (vs), 1070 (m), 1026 (m), 888 (s), and 577 (w).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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).

Figures top

	Fig. 1. An ORTEP drawing of the title compound with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. A perspective view of the packing structure of the title compound. Symmetry codes: (i) -x + 1, y - 1/2, -z + 1/2; (ii) x, -y + 3/2, z + 1/2.

2-Aminobenzimidazolium hydrogen sulfate top

Crystal data top

C₇H₈N₃⁺·HSO₄⁻	F(000) = 480
M_r = 231.23	D_x = 1.550 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1841 reflections
a = 10.855 (6) Å	θ = 1.0–1.0°
b = 13.049 (7) Å	µ = 0.33 mm⁻¹
c = 7.082 (4) Å	T = 291 K
β = 99.025 (7)°	Block, colourless
V = 990.7 (9) Å³	0.16 × 0.12 × 0.10 mm
Z = 4

Data collection top

Bruker SMART diffractometer	1841 independent reflections
Radiation source: fine-focus sealed tube	1408 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.057
ϕ and ω scans	θ_max = 25.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −13→13
T_min = 0.950, T_max = 0.968	k = −11→15
5083 measured reflections	l = −8→8

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)] = 0.038	H-atom parameters constrained
wR(F²) = 0.103	w = 1/[σ²(F_o²) + (0.0593P)²] where P = (F_o² + 2F_c²)/3
S = 0.96	(Δ/σ)_max = 0.001
1841 reflections	Δρ_max = 0.23 e Å⁻³
136 parameters	Δρ_min = −0.35 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008)
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0

Crystal data top

C₇H₈N₃⁺·HSO₄⁻	V = 990.7 (9) Å³
M_r = 231.23	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.855 (6) Å	µ = 0.33 mm⁻¹
b = 13.049 (7) Å	T = 291 K
c = 7.082 (4) Å	0.16 × 0.12 × 0.10 mm
β = 99.025 (7)°

Data collection top

Bruker SMART diffractometer	1841 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1408 reflections with I > 2σ(I)
T_min = 0.950, T_max = 0.968	R_int = 0.057
5083 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.103	H-atom parameters constrained
S = 0.96	Δρ_max = 0.23 e Å⁻³
1841 reflections	Δρ_min = −0.35 e Å⁻³
136 parameters

Special details top

Experimental. The structure was solved by direct methods (Bruker, 2000) and successive difference Fourier syntheses.

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.

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

	x	y	z	U_iso*/U_eq
C1	0.61393 (19)	0.67017 (16)	0.3926 (3)	0.0400 (5)
C2	0.80252 (18)	0.71967 (16)	0.5357 (3)	0.0387 (5)
C3	0.9247 (2)	0.72581 (18)	0.6229 (3)	0.0483 (6)
H3	0.9725	0.6674	0.6557	0.058*
C4	0.9730 (2)	0.82273 (19)	0.6594 (3)	0.0533 (6)
H4	1.0555	0.8296	0.7178	0.064*
C5	0.9026 (2)	0.91056 (19)	0.6120 (3)	0.0563 (6)
H5	0.9382	0.9746	0.6407	0.068*
C6	0.7787 (2)	0.90386 (17)	0.5216 (3)	0.0497 (6)
H6	0.7310	0.9620	0.4866	0.060*
C7	0.73133 (18)	0.80702 (16)	0.4872 (3)	0.0385 (5)
N1	0.72523 (15)	0.63593 (13)	0.4769 (2)	0.0410 (4)
H1A	0.7460	0.5725	0.4925	0.049*
N2	0.61415 (15)	0.77282 (13)	0.3989 (2)	0.0429 (5)
H2A	0.5521	0.8116	0.3555	0.051*
N3	0.51968 (16)	0.61327 (14)	0.3154 (3)	0.0534 (5)
H3A	0.5265	0.5476	0.3163	0.064*
H3B	0.4511	0.6416	0.2639	0.064*
O1	0.21109 (12)	0.84704 (11)	0.3128 (2)	0.0508 (4)
H1B	0.2450	0.8155	0.4069	0.076*
O2	0.32882 (14)	0.75437 (11)	0.1058 (2)	0.0533 (5)
O3	0.41587 (12)	0.90419 (10)	0.2672 (2)	0.0494 (4)
O4	0.23730 (14)	0.91989 (11)	0.0168 (2)	0.0539 (4)
S1	0.30277 (5)	0.85757 (4)	0.16657 (8)	0.0404 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0399 (11)	0.0385 (12)	0.0414 (12)	0.0044 (9)	0.0057 (10)	−0.0029 (9)
C2	0.0419 (12)	0.0400 (12)	0.0344 (11)	0.0037 (9)	0.0069 (9)	−0.0013 (9)
C3	0.0444 (12)	0.0581 (15)	0.0420 (13)	0.0089 (11)	0.0057 (10)	0.0033 (11)
C4	0.0416 (13)	0.0658 (17)	0.0518 (15)	−0.0066 (11)	0.0051 (11)	−0.0039 (12)
C5	0.0584 (15)	0.0548 (16)	0.0577 (15)	−0.0130 (12)	0.0151 (12)	−0.0092 (12)
C6	0.0537 (14)	0.0407 (13)	0.0552 (15)	0.0009 (10)	0.0103 (12)	−0.0020 (11)
C7	0.0401 (11)	0.0386 (12)	0.0371 (12)	0.0045 (9)	0.0073 (9)	−0.0016 (9)
N1	0.0438 (10)	0.0322 (10)	0.0453 (11)	0.0091 (7)	0.0017 (8)	−0.0001 (7)
N2	0.0404 (10)	0.0343 (10)	0.0520 (12)	0.0109 (7)	0.0013 (8)	−0.0010 (8)
N3	0.0447 (10)	0.0400 (11)	0.0719 (14)	0.0050 (8)	−0.0019 (10)	−0.0067 (10)
O1	0.0408 (8)	0.0495 (10)	0.0611 (10)	0.0055 (7)	0.0047 (8)	0.0063 (7)
O2	0.0640 (10)	0.0331 (9)	0.0582 (10)	0.0091 (7)	−0.0047 (8)	−0.0073 (7)
O3	0.0387 (8)	0.0372 (9)	0.0669 (10)	−0.0035 (6)	−0.0086 (7)	0.0032 (7)
O4	0.0609 (9)	0.0381 (9)	0.0548 (10)	0.0046 (7)	−0.0153 (8)	0.0072 (7)
S1	0.0402 (3)	0.0288 (3)	0.0484 (4)	0.0019 (2)	−0.0045 (2)	0.0007 (2)

Geometric parameters (Å, º) top

C1—N3	1.312 (3)	C6—C7	1.372 (3)
C1—N1	1.338 (2)	C6—H6	0.9300
C1—N2	1.340 (3)	C7—N2	1.400 (2)
C2—C3	1.375 (3)	N1—H1A	0.8600
C2—C7	1.390 (3)	N2—H2A	0.8600
C2—N1	1.401 (3)	N3—H3A	0.8600
C3—C4	1.378 (3)	N3—H3B	0.8600
C3—H3	0.9300	O1—S1	1.5510 (18)
C4—C5	1.389 (3)	O1—H1B	0.8200
C4—H4	0.9300	O2—S1	1.4549 (16)
C5—C6	1.398 (3)	O3—S1	1.4528 (14)
C5—H5	0.9300	O4—S1	1.4336 (15)

N3—C1—N1	126.0 (2)	C6—C7—N2	131.49 (19)
N3—C1—N2	125.21 (19)	C2—C7—N2	106.26 (18)
N1—C1—N2	108.79 (18)	C1—N1—C2	109.21 (17)
C3—C2—C7	121.5 (2)	C1—N1—H1A	125.4
C3—C2—N1	132.04 (19)	C2—N1—H1A	125.4
C7—C2—N1	106.42 (17)	C1—N2—C7	109.28 (16)
C2—C3—C4	116.7 (2)	C1—N2—H2A	125.4
C2—C3—H3	121.7	C7—N2—H2A	125.4
C4—C3—H3	121.7	C1—N3—H3A	120.0
C3—C4—C5	122.2 (2)	C1—N3—H3B	120.0
C3—C4—H4	118.9	H3A—N3—H3B	120.0
C5—C4—H4	118.9	S1—O1—H1B	109.5
C4—C5—C6	120.8 (2)	O4—S1—O3	114.09 (9)
C4—C5—H5	119.6	O4—S1—O2	113.76 (10)
C6—C5—H5	119.6	O3—S1—O2	110.13 (9)
C7—C6—C5	116.5 (2)	O4—S1—O1	104.41 (10)
C7—C6—H6	121.8	O3—S1—O1	106.91 (10)
C5—C6—H6	121.8	O2—S1—O1	106.88 (10)
C6—C7—C2	122.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4ⁱ	0.86	2.00	2.848 (3)	167
O1—H1B···O2ⁱⁱ	0.82	1.80	2.619 (2)	176
N2—H2A···O3	0.86	1.94	2.795 (2)	177
N3—H3A···O3ⁱ	0.86	2.09	2.899 (3)	157
N3—H3B···O2	0.86	2.17	2.987 (2)	158

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) x, −y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₇H₈N₃⁺·HSO₄⁻
M_r	231.23
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	291
a, b, c (Å)	10.855 (6), 13.049 (7), 7.082 (4)
β (°)	99.025 (7)
V (Å³)	990.7 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.33
Crystal size (mm)	0.16 × 0.12 × 0.10

Data collection
Diffractometer	Bruker SMART diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.950, 0.968
No. of measured, independent and observed [I > 2σ(I)] reflections	5083, 1841, 1408
R_int	0.057
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.103, 0.96
No. of reflections	1841
No. of parameters	136
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.35

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O4ⁱ	0.86	2.00	2.848 (3)	167
O1—H1B···O2ⁱⁱ	0.82	1.80	2.619 (2)	176
N2—H2A···O3	0.86	1.94	2.795 (2)	177
N3—H3A···O3ⁱ	0.86	2.09	2.899 (3)	157
N3—H3B···O2	0.86	2.17	2.987 (2)	158

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) x, −y+3/2, z+1/2.

Footnotes

‡Additional correspondence author.

Acknowledgements

WH acknowledges the National Natural Science Foundation of China (No. 20871065) and the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry, for financial aid.

References

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Yeşilel, O. Z., Odabaşoğlu, M. & Büyükgüngör, O. (2008). J. Mol. Struct. 874, 151–158. Google Scholar