Benzimidazolium perchlorate

Sieroń, L.

doi:10.1107/S1600536807035428

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Benzimidazolium perchlorate

L. Sieroń

The asymmetric unit of the title salt, C₇H₇N₂⁺·ClO₄⁻, consists of two benzimidazolium cations and two perchlorate anions linked by N—H

O hydrogen bonds into sheets of alternating edge-fused R³₄(12) rings, which run parallel to the (102) plane.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807035428/bq2032sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536807035428/bq2032Isup2.hkl Contains datablock I

CCDC reference: 657824

checkCIF report

Key indicators

Single-crystal X-ray study
T = 297 K
Mean (C-C) = 0.005 Å
R factor = 0.041
wR factor = 0.112
Data-to-parameter ratio = 11.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.15
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N11    -   C18     ..       6.04 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Cl1
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Cl2
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5
PLAT430_ALERT_2_C Short Inter D...A Contact  O1     ..  O12     ..       2.88 Ang.
PLAT430_ALERT_2_C Short Inter D...A Contact  O2     ..  O11     ..       2.88 Ang.

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           25.00
           From the CIF: _reflns_number_total               2923
           Count of symmetry unique reflns         1566
           Completeness (_total/calc)            186.65%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1357
           Fraction of Friedel pairs measured     0.867
           Are heavy atom types Z>Si present        yes
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   7 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

Comment top

The title compound, (I), was investigated as part of a structural study on hydrogen bonding in N-heterocyclic perchlorate salts (Sieroń, 2005a, b, 2007a, b, c). In (I), the asymmetric unit is composed of two benzimidazolium cations and two perchlorate anions (Fig. 1). The cations and anions are linked together by intermolecular N–H···O hydrogen bonds, forming fused 12-membered rings, described by the graph-set notations as R³₄(12) (Etter et al., 1990). The substructure based on these motif forms layers lying parallel to the (102) plane (Fig. 2). The distance between neighboring planes is ca 3.3 Å. One of the N-bonded H atoms of both benzotriazolium cations are engaged in a bifurcated unsymmetrical (strong and weak) hydrogen bonds. Each of these hydrogen bonds involve two perchlorate O atoms. A bifurcation is confirmed by the sums of angles about atoms H1 and H11, which are 355.5° and 357.9°, respectively (Jeffrey & Saenger, 1991). The crystal packing is stabilized by weak intermolecular C–H···O interactions to build up a three-dimensional network.

Related literature top

For related structures, see: Sieroń (2005a,b, 2007a,b,c). For related literature, see: Etter et al. (1990); Jeffrey & Saenger (1991).

Experimental top

The title compound was prepared by reaction of stoichiometric amounts of benzimidazole and perchloric acid. The resulting solid was recrystallized from water at room temperature.

Structure description top

For related structures, see: Sieroń (2005a,b, 2007a,b,c). For related literature, see: Etter et al. (1990); Jeffrey & Saenger (1991).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and Mercury (Macrae et al., 2006); software used to prepare material for publication: PLATON (Spek, 2003).

Figures top

	Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms.
	Fig. 2. The packing of (I), showing molecules connected by N—H···O hydrogen bonds (dashed lines) into sheets approximately parallel to the (102) plane.

Benzimidazolium perchlorate top

Crystal data top

C₇H₇N₂⁺·ClO₄⁻	F(000) = 896
M_r = 218.60	D_x = 1.689 Mg m⁻³
Orthorhombic, Pca2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2ac	Cell parameters from 11107 reflections
a = 9.9885 (2) Å	θ = 3.0–29.0°
b = 9.0509 (1) Å	µ = 0.43 mm⁻¹
c = 19.0182 (3) Å	T = 297 K
V = 1719.34 (5) Å³	Plate, colourless
Z = 8	0.60 × 0.30 × 0.06 mm

Data collection top

Kuma KM4 CCD area-detector diffractometer	2923 independent reflections
Radiation source: CX-Mo12x0.4-S Seifert Mo tube	2676 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
Detector resolution: 8.2356 pixels mm^-1	θ_max = 25.0°, θ_min = 3.0°
ω scans	h = −11→11
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −10→10
T_min = 0.781, T_max = 0.974	l = −22→22
16719 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: difference Fourier map
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.041	w = 1/[σ²(F_o²) + (0.0829P)² + 0.431P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.112	(Δ/σ)_max = 0.001
S = 1.06	Δρ_max = 0.87 e Å⁻³
2923 reflections	Δρ_min = −0.40 e Å⁻³
253 parameters	Absolute structure: Flack (1983), with 1462 Friedel pairs
1 restraint	Absolute structure parameter: 0.04 (6)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₇H₇N₂⁺·ClO₄⁻	V = 1719.34 (5) Å³
M_r = 218.60	Z = 8
Orthorhombic, Pca2₁	Mo Kα radiation
a = 9.9885 (2) Å	µ = 0.43 mm⁻¹
b = 9.0509 (1) Å	T = 297 K
c = 19.0182 (3) Å	0.60 × 0.30 × 0.06 mm

Data collection top

Kuma KM4 CCD area-detector diffractometer	2923 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	2676 reflections with I > 2σ(I)
T_min = 0.781, T_max = 0.974	R_int = 0.018
16719 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	H-atom parameters constrained
wR(F²) = 0.112	Δρ_max = 0.87 e Å⁻³
S = 1.06	Δρ_min = −0.40 e Å⁻³
2923 reflections	Absolute structure: Flack (1983), with 1462 Friedel pairs
253 parameters	Absolute structure parameter: 0.04 (6)
1 restraint

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F² for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The observed criterion of F² > σ(F²) is used only for calculating -R-factor-obs 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
N1	0.1711 (3)	1.0228 (3)	0.83955 (19)	0.0372 (9)
N3	0.1090 (3)	0.8084 (3)	0.87538 (15)	0.0407 (9)
C2	0.1928 (3)	0.8817 (4)	0.83387 (18)	0.0429 (10)
C4	−0.0706 (4)	0.8899 (5)	0.96160 (19)	0.0443 (13)
C5	−0.1273 (4)	1.0173 (5)	0.9862 (3)	0.0467 (12)
C6	−0.0876 (4)	1.1586 (4)	0.9630 (2)	0.0432 (11)
C7	0.0100 (3)	1.1771 (4)	0.9134 (2)	0.0408 (11)
C8	0.0692 (4)	1.0482 (4)	0.88770 (18)	0.0339 (11)
C9	0.0286 (3)	0.9077 (3)	0.91156 (19)	0.0349 (10)
N11	0.0702 (3)	0.4754 (4)	0.69468 (19)	0.0373 (9)
N13	0.1382 (3)	0.6899 (3)	0.66146 (16)	0.0401 (9)
C12	0.0526 (3)	0.6176 (4)	0.70226 (18)	0.0419 (10)
C14	0.3180 (4)	0.6058 (4)	0.57613 (19)	0.0381 (11)
C15	0.3723 (4)	0.4758 (5)	0.5490 (2)	0.0457 (14)
C16	0.3277 (4)	0.3378 (5)	0.5725 (2)	0.0473 (12)
C17	0.2294 (4)	0.3210 (4)	0.62179 (18)	0.0397 (10)
C18	0.1730 (4)	0.4499 (4)	0.64646 (18)	0.0335 (11)
C19	0.2161 (3)	0.5872 (4)	0.62590 (17)	0.0321 (10)
Cl1	0.44447 (8)	0.96264 (9)	0.68820 (4)	0.0339 (3)
O1	0.3939 (3)	1.0716 (3)	0.73581 (17)	0.0557 (10)
O2	0.4461 (3)	0.8223 (3)	0.72205 (16)	0.0645 (10)
O3	0.5778 (3)	1.0008 (3)	0.6670 (2)	0.0581 (15)
O4	0.3618 (3)	0.9553 (4)	0.6270 (2)	0.0717 (12)
Cl2	0.29983 (8)	0.46265 (9)	0.84884 (4)	0.0350 (3)
O11	0.3484 (3)	0.5709 (3)	0.79958 (17)	0.0554 (9)
O12	0.2998 (4)	0.3209 (3)	0.81592 (16)	0.0672 (11)
O13	0.1659 (3)	0.4988 (3)	0.8680 (2)	0.0541 (13)
O14	0.3814 (3)	0.4610 (4)	0.9092 (2)	0.0743 (12)
H1	0.21380	1.09040	0.81700	0.0450*
H2	0.25720	0.83860	0.80510	0.0520*
H3	0.10520	0.71380	0.87920	0.0490*
H4	−0.09700	0.79720	0.97750	0.0530*
H5	−0.19490	1.01040	1.01960	0.0560*
H6	−0.12900	1.24150	0.98200	0.0520*
H7	0.03560	1.27020	0.89760	0.0490*
H11	0.02560	0.40790	0.71620	0.0450*
H12	−0.01030	0.66140	0.73170	0.0500*
H13	0.14440	0.78440	0.65780	0.0480*
H14	0.34750	0.69870	0.56210	0.0460*
H15	0.43890	0.48090	0.51490	0.0550*
H16	0.36680	0.25340	0.55360	0.0570*
H17	0.20230	0.22860	0.63770	0.0480*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0363 (16)	0.0406 (15)	0.0346 (18)	−0.0029 (13)	0.0032 (15)	0.0083 (13)
N3	0.0473 (17)	0.0253 (14)	0.0495 (16)	0.0056 (12)	−0.0026 (14)	−0.0043 (12)
C2	0.0382 (16)	0.047 (2)	0.0436 (17)	0.0074 (17)	−0.0005 (15)	−0.0034 (16)
C4	0.045 (2)	0.054 (3)	0.0339 (18)	−0.0130 (18)	0.0038 (16)	0.0057 (18)
C5	0.038 (2)	0.065 (2)	0.037 (2)	−0.0036 (18)	0.0033 (18)	−0.0060 (17)
C6	0.0455 (19)	0.039 (2)	0.045 (2)	0.0018 (16)	−0.0006 (16)	−0.0139 (17)
C7	0.0388 (19)	0.0317 (17)	0.052 (2)	−0.0025 (14)	−0.0051 (16)	−0.0034 (16)
C8	0.0323 (18)	0.037 (2)	0.0324 (17)	−0.0023 (15)	−0.0012 (14)	0.0060 (14)
C9	0.0382 (18)	0.0243 (16)	0.0421 (18)	−0.0040 (14)	−0.0070 (15)	−0.0011 (15)
N11	0.0297 (15)	0.0434 (15)	0.0388 (18)	0.0000 (13)	0.0066 (15)	−0.0014 (14)
N13	0.0439 (16)	0.0274 (14)	0.0490 (15)	0.0046 (12)	−0.0033 (13)	−0.0019 (12)
C12	0.0366 (16)	0.050 (2)	0.0391 (16)	0.0068 (16)	0.0030 (15)	−0.0066 (15)
C14	0.0400 (19)	0.034 (2)	0.0402 (19)	−0.0049 (15)	−0.0035 (15)	0.0091 (16)
C15	0.038 (2)	0.068 (3)	0.031 (2)	0.0022 (18)	0.0044 (18)	−0.0073 (19)
C16	0.043 (2)	0.050 (2)	0.049 (2)	0.0070 (18)	−0.0005 (17)	−0.0135 (18)
C17	0.046 (2)	0.0269 (16)	0.0463 (18)	−0.0016 (14)	−0.0029 (16)	−0.0004 (14)
C18	0.0352 (18)	0.0297 (19)	0.0356 (18)	−0.0004 (14)	−0.0069 (15)	−0.0008 (14)
C19	0.0330 (18)	0.0338 (18)	0.0295 (15)	0.0078 (14)	−0.0050 (13)	−0.0033 (14)
Cl1	0.0330 (4)	0.0262 (4)	0.0425 (5)	−0.0005 (3)	0.0064 (4)	−0.0017 (4)
O1	0.0638 (18)	0.0384 (16)	0.0648 (18)	0.0065 (13)	0.0235 (15)	−0.0125 (13)
O2	0.094 (2)	0.0277 (15)	0.0718 (19)	−0.0002 (12)	0.0220 (16)	0.0107 (13)
O3	0.0322 (16)	0.0402 (17)	0.102 (4)	−0.0037 (11)	0.0316 (18)	−0.0026 (14)
O4	0.068 (2)	0.077 (2)	0.070 (2)	0.0044 (19)	−0.0172 (18)	−0.0132 (19)
Cl2	0.0340 (4)	0.0273 (4)	0.0436 (5)	0.0016 (3)	0.0077 (4)	0.0039 (4)
O11	0.0701 (18)	0.0360 (15)	0.0600 (16)	−0.0022 (13)	0.0253 (15)	0.0144 (13)
O12	0.099 (2)	0.0226 (14)	0.080 (2)	−0.0070 (13)	0.0311 (17)	−0.0102 (13)
O13	0.0418 (17)	0.0396 (17)	0.081 (3)	0.0061 (11)	0.0095 (18)	0.0030 (13)
O14	0.068 (2)	0.089 (2)	0.066 (2)	−0.0168 (19)	−0.0248 (18)	0.022 (2)

Geometric parameters (Å, º) top

Cl1—O1	1.431 (3)	C4—C9	1.383 (5)
Cl1—O2	1.424 (3)	C5—C6	1.410 (6)
Cl1—O3	1.434 (3)	C6—C7	1.367 (5)
Cl1—O4	1.429 (4)	C7—C8	1.396 (5)
Cl2—O11	1.440 (3)	C8—C9	1.410 (5)
Cl2—O12	1.428 (3)	C2—H2	0.93
Cl2—O13	1.425 (3)	C4—H4	0.93
Cl2—O14	1.408 (4)	C5—H5	0.93
N1—C2	1.300 (5)	C6—H6	0.93
N1—C8	1.388 (5)	C7—H7	0.93
N3—C2	1.328 (4)	C14—C19	1.400 (5)
N3—C9	1.388 (4)	C14—C15	1.395 (6)
N1—H1	0.86	C15—C16	1.399 (6)
N3—H3	0.86	C16—C17	1.366 (5)
N11—C12	1.307 (5)	C17—C18	1.378 (5)
N11—C18	1.396 (5)	C18—C19	1.372 (5)
N13—C19	1.388 (4)	C12—H12	0.93
N13—C12	1.327 (4)	C14—H14	0.93
N11—H11	0.86	C15—H15	0.93
N13—H13	0.86	C16—H16	0.93
C4—C5	1.367 (6)	C17—H17	0.93

O1—Cl1—O2	109.43 (18)	N3—C9—C4	132.9 (3)
O1—Cl1—O3	109.87 (18)	N3—C9—C8	105.0 (3)
O1—Cl1—O4	110.09 (19)	N1—C2—H2	125
O2—Cl1—O3	109.35 (18)	N3—C2—H2	125
O2—Cl1—O4	109.5 (2)	C5—C4—H4	122
O3—Cl1—O4	108.6 (2)	C9—C4—H4	122
O11—Cl2—O12	109.04 (18)	C6—C5—H5	119
O11—Cl2—O13	109.06 (18)	C4—C5—H5	119
O11—Cl2—O14	110.05 (19)	C5—C6—H6	119
O12—Cl2—O13	108.6 (2)	C7—C6—H6	119
O12—Cl2—O14	110.4 (2)	C8—C7—H7	122
O13—Cl2—O14	109.7 (2)	C6—C7—H7	122
C2—N1—C8	109.9 (3)	N11—C12—N13	109.5 (3)
C2—N3—C9	109.6 (3)	C15—C14—C19	115.6 (3)
C2—N3—H3	125	C14—C15—C16	120.7 (4)
C2—N1—H1	125	C15—C16—C17	123.2 (4)
C8—N1—H1	125	C16—C17—C18	115.7 (4)
C9—N3—H3	125	N11—C18—C17	131.6 (3)
C12—N11—C18	109.5 (3)	C17—C18—C19	122.8 (3)
C12—N13—C19	108.4 (3)	N11—C18—C19	105.6 (3)
C12—N11—H11	125	N13—C19—C18	107.0 (3)
C18—N11—H11	125	N13—C19—C14	131.0 (3)
C12—N13—H13	126	C14—C19—C18	122.0 (3)
C19—N13—H13	126	N11—C12—H12	125
N1—C2—N3	109.7 (3)	N13—C12—H12	125
C5—C4—C9	115.7 (4)	C15—C14—H14	122
C4—C5—C6	122.8 (4)	C19—C14—H14	122
C5—C6—C7	121.9 (4)	C14—C15—H15	120
C6—C7—C8	116.2 (3)	C16—C15—H15	120
N1—C8—C7	132.8 (3)	C15—C16—H16	118
C7—C8—C9	121.3 (3)	C17—C16—H16	118
N1—C8—C9	105.9 (3)	C18—C17—H17	122
C4—C9—C8	122.2 (3)	C16—C17—H17	122

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.86	2.38	3.007 (5)	130
N1—H1···O12ⁱ	0.86	2.26	3.022 (4)	148
N3—H3···O13	0.86	2.05	2.863 (4)	157
N11—H11···O11ⁱⁱ	0.86	2.38	3.011 (5)	130
N11—H11···O2ⁱⁱ	0.86	2.23	3.011 (4)	151
N13—H13···O3ⁱⁱⁱ	0.86	2.06	2.866 (4)	155
C2—H2···O2	0.93	2.47	3.349 (4)	159
C2—H2···O11	0.93	2.59	3.279 (4)	131
C7—H7···O13ⁱ	0.93	2.51	3.413 (5)	164
C12—H12···O12ⁱⁱ	0.93	2.49	3.370 (5)	158
C17—H17···O3ⁱⁱ	0.93	2.48	3.393 (5)	166

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

Experimental details

Crystal data
Chemical formula	C₇H₇N₂⁺·ClO₄⁻
M_r	218.60
Crystal system, space group	Orthorhombic, Pca2₁
Temperature (K)	297
a, b, c (Å)	9.9885 (2), 9.0509 (1), 19.0182 (3)
V (Å³)	1719.34 (5)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.43
Crystal size (mm)	0.60 × 0.30 × 0.06

Data collection
Diffractometer	Kuma KM4 CCD area-detector
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.781, 0.974
No. of measured, independent and observed [I > 2σ(I)] reflections	16719, 2923, 2676
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.112, 1.06
No. of reflections	2923
No. of parameters	253
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.87, −0.40
Absolute structure	Flack (1983), with 1462 Friedel pairs
Absolute structure parameter	0.04 (6)

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), CrysAlis RED, SHELXTL (Sheldrick, 2001), SHELXTL and Mercury (Macrae et al., 2006), PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.86	2.38	3.007 (5)	130
N1—H1···O12ⁱ	0.86	2.26	3.022 (4)	148
N3—H3···O13	0.86	2.05	2.863 (4)	157
N11—H11···O11ⁱⁱ	0.86	2.38	3.011 (5)	130
N11—H11···O2ⁱⁱ	0.86	2.23	3.011 (4)	151
N13—H13···O3ⁱⁱⁱ	0.86	2.06	2.866 (4)	155
C2—H2···O2	0.93	2.47	3.349 (4)	159
C2—H2···O11	0.93	2.59	3.279 (4)	131
C7—H7···O13ⁱ	0.93	2.51	3.413 (5)	164
C12—H12···O12ⁱⁱ	0.93	2.49	3.370 (5)	158
C17—H17···O3ⁱⁱ	0.93	2.48	3.393 (5)	166

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

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