2-Amino-6-nitro-1H-benzoimidazol-3-ium chloride.

In the cation of the title compound, C(7)H(7)N(4)O(2) (+)·Cl(-), the benzimidazole ring system is planar with a maximum deviation of -0.019 (3) Å. In the crystal structure, C-H⋯Cl, N-H⋯Cl, and N-H⋯Cl inter-actions link the mol-ecules into a two-dimensional network. π-π contacts between benzimidazole rings [centroid-centroid distances = 3.928 (1) and 3.587 (1) Å] may further stabilize the structure.

Related literature

For bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

C7H7N4O2 +·Cl−

M = 214.62

Monoclinic,

a = 13.969 (3) Å

b = 7.8064 (19) Å

c = 16.490 (4) Å

β = 91.303 (3)°

V = 1797.7 (7) Å3

Z = 8

Mo Kα radiation

μ = 0.40 mm−1

T = 291 K

0.12 × 0.12 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer

Absorption correction: ψ scan (North et al., 1968 ▶) T min = 0.953, T max = 0.961

4345 measured reflections

1580 independent reflections

1242 reflections with I > 2σ(I)

R int = 0.041

3 standard reflections frequency: 120 min intensity decay: none

Refinement

R[F 2 > 2σ(F 2)] = 0.035

wR(F 2) = 0.096

S = 1.02

1580 reflections

127 parameters

H-atom parameters constrained

Δρmax = 0.18 e Å−3

Δρmin = −0.20 e Å−3

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97 and PLATON.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809027342/hk2728sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809027342/hk2728Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C7H7N4O2+·Cl−	F(000) = 880
Mr = 214.62	Dx = 1.586 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 25 reflections
a = 13.969 (3) Å	θ = 2.1–25.3°
b = 7.8064 (19) Å	µ = 0.40 mm−1
c = 16.490 (4) Å	T = 291 K
β = 91.303 (3)°	Block, yellow
V = 1797.7 (7) Å3	0.12 × 0.12 × 0.10 mm
Z = 8

Enraf–Nonius CAD-4 diffractometer	1242 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.041
graphite	θmax = 25.0°, θmin = 2.5°
ω/2θ scans	h = −16→16
Absorption correction: ψ scan (North et al., 1968)	k = −9→9
Tmin = 0.953, Tmax = 0.961	l = −19→13
4345 measured reflections	3 standard reflections every 120 min
1580 independent reflections	intensity decay: none

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096	H-atom parameters constrained
S = 1.02	w = 1/[σ2(Fo2) + (0.0429P)2 + 0.969P] where P = (Fo2 + 2Fc2)/3
1580 reflections	(Δ/σ)max < 0.001
127 parameters	Δρmax = 0.18 e Å−3
0 restraints	Δρmin = −0.19 e Å−3

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
Cl1	0.40318 (4)	0.59647 (8)	0.67245 (4)	0.0535 (2)
O1	0.38248 (13)	0.6546 (3)	0.39469 (12)	0.0718 (6)
O2	0.42766 (13)	0.8483 (3)	0.31128 (11)	0.0743 (6)
N1	0.61668 (12)	0.7489 (2)	0.63485 (10)	0.0424 (5)
H1A	0.5835	0.6840	0.6656	0.051*
N2	0.72946 (12)	0.9189 (2)	0.59344 (10)	0.0403 (4)
H2A	0.7805	0.9804	0.5934	0.048*
N3	0.73958 (14)	0.8248 (3)	0.72889 (12)	0.0552 (6)
H3A	0.7916	0.8812	0.7380	0.066*
H3B	0.7150	0.7649	0.7669	0.066*
N4	0.43847 (13)	0.7660 (3)	0.37360 (12)	0.0491 (5)
C1	0.69763 (15)	0.8301 (3)	0.65691 (13)	0.0392 (5)
C2	0.59515 (14)	0.7865 (3)	0.55416 (12)	0.0363 (5)
C3	0.66716 (14)	0.8960 (3)	0.52782 (13)	0.0361 (5)
C4	0.66616 (16)	0.9615 (3)	0.44987 (13)	0.0420 (5)
H4	0.7147	1.0332	0.4323	0.050*
C5	0.59021 (16)	0.9163 (3)	0.39925 (13)	0.0432 (5)
H5	0.5859	0.9590	0.3466	0.052*
C6	0.52047 (15)	0.8067 (3)	0.42752 (13)	0.0392 (5)
C7	0.52051 (15)	0.7385 (3)	0.50434 (13)	0.0401 (5)
H7	0.4728	0.6644	0.5213	0.048*

	U11	U22	U33	U12	U13	U23
Cl1	0.0422 (4)	0.0708 (4)	0.0475 (4)	−0.0144 (3)	0.0034 (3)	−0.0083 (3)
O1	0.0580 (12)	0.0805 (13)	0.0762 (13)	−0.0252 (10)	−0.0151 (10)	0.0019 (11)
O2	0.0612 (12)	0.1070 (16)	0.0539 (12)	−0.0053 (11)	−0.0168 (9)	0.0130 (11)
N1	0.0447 (11)	0.0431 (11)	0.0393 (11)	−0.0091 (9)	0.0011 (8)	0.0035 (8)
N2	0.0328 (10)	0.0461 (11)	0.0419 (10)	−0.0076 (8)	−0.0012 (8)	0.0000 (8)
N3	0.0523 (13)	0.0663 (14)	0.0466 (12)	−0.0117 (10)	−0.0096 (10)	0.0075 (10)
N4	0.0387 (11)	0.0593 (13)	0.0491 (12)	0.0016 (10)	−0.0039 (9)	−0.0090 (10)
C1	0.0351 (11)	0.0413 (12)	0.0411 (13)	0.0005 (9)	−0.0013 (9)	−0.0016 (10)
C2	0.0357 (11)	0.0366 (11)	0.0367 (12)	0.0003 (9)	0.0019 (9)	−0.0012 (9)
C3	0.0311 (11)	0.0368 (11)	0.0405 (12)	0.0005 (9)	0.0022 (9)	−0.0035 (9)
C4	0.0372 (12)	0.0445 (13)	0.0446 (13)	−0.0050 (10)	0.0064 (10)	0.0019 (10)
C5	0.0430 (13)	0.0479 (13)	0.0387 (12)	0.0007 (10)	0.0026 (10)	0.0006 (10)
C6	0.0364 (12)	0.0420 (12)	0.0391 (12)	0.0023 (9)	−0.0021 (9)	−0.0063 (10)
C7	0.0362 (12)	0.0393 (12)	0.0448 (13)	−0.0059 (9)	0.0039 (10)	−0.0051 (10)

N1—H1A	0.8600	C2—C7	1.365 (3)
N2—H2A	0.8600	C3—N2	1.385 (3)
N3—H3A	0.8600	C3—C4	1.383 (3)
N3—H3B	0.8600	C4—C5	1.381 (3)
N4—O1	1.225 (3)	C4—H4	0.9300
N4—O2	1.219 (2)	C5—C6	1.385 (3)
C1—N1	1.340 (3)	C5—H5	0.9300
C1—N2	1.340 (3)	C6—C7	1.374 (3)
C1—N3	1.312 (3)	C6—N4	1.469 (3)
C2—N1	1.389 (3)	C7—H7	0.9300
C2—C3	1.397 (3)
C1—N1—C2	108.84 (17)	C7—C2—C3	121.8 (2)
C1—N1—H1A	125.6	N2—C3—C2	106.28 (18)
C2—N1—H1A	125.6	C4—C3—N2	132.2 (2)
C1—N2—C3	109.26 (17)	C4—C3—C2	121.6 (2)
C1—N2—H2A	125.4	C3—C4—H4	121.4
C3—N2—H2A	125.4	C5—C4—C3	117.3 (2)
C1—N3—H3A	120.0	C5—C4—H4	121.4
C1—N3—H3B	120.0	C4—C5—C6	119.4 (2)
H3A—N3—H3B	120.0	C4—C5—H5	120.3
O1—N4—C6	118.4 (2)	C6—C5—H5	120.3
O2—N4—O1	123.1 (2)	C5—C6—N4	118.3 (2)
O2—N4—C6	118.5 (2)	C7—C6—N4	117.27 (19)
N2—C1—N1	109.02 (18)	C7—C6—C5	124.3 (2)
N3—C1—N1	126.0 (2)	C2—C7—C6	115.6 (2)
N3—C1—N2	125.0 (2)	C2—C7—H7	122.2
N1—C2—C3	106.60 (18)	C6—C7—H7	122.2
C7—C2—N1	131.6 (2)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7···Cl1	0.93	2.75	3.436 (2)	132
N1—H1A···Cl1	0.86	2.61	3.2830 (19)	135
N1—H1A···Cl1i	0.86	2.76	3.4102 (19)	134
N3—H3A···Cl1ii	0.86	2.55	3.269 (2)	142
N2—H2A···Cl1ii	0.86	2.31	3.0601 (19)	145

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7⋯Cl1	0.93	2.75	3.436 (2)	132
N1—H1A⋯Cl1	0.86	2.61	3.2830 (19)	135
N1—H1A⋯Cl1i	0.86	2.76	3.4102 (19)	134
N3—H3A⋯Cl1ii	0.86	2.55	3.269 (2)	142
N2—H2A⋯Cl1ii	0.86	2.31	3.0601 (19)	145

Symmetry codes: (i) ; (ii) .