2-(2,4-Dichloro­phen­yl)-1H-benzimidazole

The title compound, C₁₃H₈Cl₂N₂, was prepared by reaction of ο-phenyl­enediamine with 2,4-dichloro­benzaldehyde under reflux in ethanol. The dihedral angle between the benzimidazole system and the benzene ring is 42.00 (15)°. In the crystal structure, intermolecular N—H...N inter­actions are present.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.050
• wR factor = 0.156
• Data-to-parameter ratio = 16.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT030_ALERT_1_C _diffrn_reflns_number .LE.  _reflns_number_total          ?
PLAT031_ALERT_4_C Refined Extinction Parameter within Range ......       2.57 Sigma
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          5

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 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

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Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: NRCVAX (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1990); software used to prepare material for publication: WinGX (Farrugia, 1999).

2-(2,4-Dichlorophenyl)-1H-benzimidazole

Crystal data

C13H8Cl2N2	F(000) = 1072
Mr = 263.11	Dx = 1.435 Mg m^−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 25 reflections
a = 8.5630 (17) Å	θ = 4–14°
b = 9.910 (2) Å	µ = 0.51 mm^−1
c = 28.694 (6) Å	T = 295 K
V = 2435.0 (9) Å^3	Block, yellow
Z = 8	0.30 × 0.20 × 0.15 mm

Data collection

Bruker P4 diffractometer	Rint = 0.000
Radiation source: fine-focus sealed tube	θmax = 27.0°, θmin = 1.4°
Graphite monochromator	h = −10→10
ω scans	k = −12→12
2602 measured reflections	l = −36→36
2602 independent reflections	3 standard reflections every 100 reflections
1316 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.050	H-atom parameters constrained
wR(F^2) = 0.156	w = 1/[σ^2(Fo^2) + (0.0711P)^2 + 0.589P] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
2602 reflections	Δρmax = 0.28 e Å^−3
155 parameters	Δρmin = −0.35 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0018 (7)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.21343 (11)	0.07444 (12)	0.05040 (3)	0.0723 (4)
Cl2	−0.39874 (13)	0.18750 (17)	0.04715 (5)	0.1087 (6)
N1	0.3227 (3)	0.1713 (2)	0.14976 (9)	0.0389 (6)
H1A	0.3131	0.0871	0.1430	0.047*
N2	0.2710 (3)	0.3937 (2)	0.15192 (9)	0.0406 (6)
C1	0.5670 (4)	0.1752 (3)	0.19938 (11)	0.0468 (8)
H1B	0.5886	0.0833	0.1986	0.056*
C2	0.6596 (4)	0.2634 (3)	0.22402 (12)	0.0531 (9)
H2B	0.7449	0.2302	0.2405	0.064*
C3	0.6279 (4)	0.4038 (3)	0.22489 (12)	0.0508 (9)
H3A	0.6932	0.4608	0.2418	0.061*
C4	0.5033 (4)	0.4571 (3)	0.20141 (11)	0.0459 (8)
H4A	0.4835	0.5494	0.2020	0.055*
C5	0.4061 (3)	0.3692 (3)	0.17650 (11)	0.0354 (7)
C6	0.4401 (3)	0.2289 (3)	0.17576 (10)	0.0361 (7)
C7	0.2248 (3)	0.2727 (3)	0.13667 (10)	0.0357 (7)
C8	0.0770 (4)	0.2514 (3)	0.11164 (11)	0.0416 (8)
C9	−0.0532 (4)	0.3232 (3)	0.12684 (14)	0.0587 (10)
H9A	−0.0417	0.3841	0.1513	0.070*
C10	−0.1982 (4)	0.3072 (4)	0.10696 (16)	0.0688 (12)
H10A	−0.2835	0.3564	0.1176	0.083*
C11	−0.2139 (4)	0.2165 (5)	0.07099 (14)	0.0661 (11)
C12	−0.0891 (4)	0.1436 (4)	0.05448 (13)	0.0642 (11)
H12A	−0.1023	0.0825	0.0302	0.077*
C13	0.0560 (4)	0.1620 (3)	0.07434 (12)	0.0497 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0582 (6)	0.0942 (8)	0.0646 (6)	0.0107 (6)	−0.0073 (5)	−0.0348 (6)
Cl2	0.0455 (6)	0.1759 (15)	0.1047 (10)	−0.0213 (8)	−0.0216 (6)	0.0118 (10)
N1	0.0442 (15)	0.0208 (12)	0.0518 (16)	−0.0025 (11)	−0.0044 (12)	−0.0026 (12)
N2	0.0420 (15)	0.0249 (13)	0.0549 (16)	−0.0001 (11)	−0.0030 (13)	−0.0054 (12)
C1	0.054 (2)	0.0302 (16)	0.057 (2)	0.0012 (16)	−0.0123 (17)	0.0023 (15)
C2	0.052 (2)	0.048 (2)	0.060 (2)	−0.0006 (17)	−0.0177 (18)	0.0051 (17)
C3	0.056 (2)	0.041 (2)	0.056 (2)	−0.0145 (17)	−0.0072 (18)	−0.0056 (16)
C4	0.0504 (19)	0.0283 (16)	0.059 (2)	−0.0062 (15)	−0.0047 (17)	−0.0057 (15)
C5	0.0409 (17)	0.0237 (14)	0.0414 (17)	−0.0007 (13)	0.0010 (14)	0.0004 (13)
C6	0.0418 (17)	0.0262 (15)	0.0402 (17)	−0.0036 (13)	−0.0009 (14)	−0.0006 (13)
C7	0.0388 (17)	0.0252 (15)	0.0431 (17)	−0.0004 (14)	0.0017 (14)	−0.0018 (13)
C8	0.0398 (18)	0.0353 (17)	0.0497 (19)	−0.0024 (15)	0.0002 (15)	0.0036 (15)
C9	0.049 (2)	0.049 (2)	0.079 (3)	0.0028 (18)	−0.003 (2)	−0.010 (2)
C10	0.042 (2)	0.080 (3)	0.085 (3)	0.009 (2)	0.002 (2)	0.001 (2)
C11	0.040 (2)	0.093 (3)	0.065 (2)	−0.013 (2)	−0.0071 (18)	0.015 (2)
C12	0.051 (2)	0.087 (3)	0.054 (2)	−0.017 (2)	−0.0064 (19)	−0.016 (2)
C13	0.049 (2)	0.052 (2)	0.048 (2)	−0.0017 (17)	0.0011 (16)	−0.0015 (17)

Geometric parameters (Å, º)

Cl1—C13	1.744 (4)	C4—C5	1.401 (4)
Cl2—C11	1.748 (4)	C4—H4A	0.9300
N1—C7	1.362 (4)	C5—C6	1.421 (4)
N1—C6	1.376 (4)	C7—C8	1.470 (4)
N1—H1A	0.8600	C8—C9	1.392 (5)
N2—C7	1.337 (4)	C8—C13	1.401 (5)
N2—C5	1.376 (4)	C9—C10	1.376 (5)
C1—C2	1.376 (4)	C9—H9A	0.9300
C1—C6	1.387 (4)	C10—C11	1.375 (6)
C1—H1B	0.9300	C10—H10A	0.9300
C2—C3	1.418 (5)	C11—C12	1.375 (5)
C2—H2B	0.9300	C12—C13	1.379 (5)
C3—C4	1.369 (4)	C12—H12A	0.9300
C3—H3A	0.9300
C7—N1—C6	107.1 (2)	C10—C11—Cl2	119.3 (3)
C7—N2—C5	105.0 (2)	C11—C12—C13	119.3 (4)
C2—C1—C6	117.4 (3)	C12—C13—C8	121.0 (3)
C1—C2—C3	121.5 (3)	C12—C13—Cl1	117.9 (3)
C4—C3—C2	121.3 (3)	C8—C13—Cl1	121.1 (3)
C3—C4—C5	118.3 (3)	C6—N1—H1A	126.47
N2—C5—C4	130.6 (3)	C7—N1—H1A	126.47
N2—C5—C6	109.7 (2)	C2—C1—H1B	121.33
C4—C5—C6	119.7 (3)	C6—C1—H1B	121.32
N1—C6—C1	132.7 (3)	C1—C2—H2B	119.26
N1—C6—C5	105.3 (3)	C3—C2—H2B	119.26
C1—C6—C5	121.9 (3)	C2—C3—H3A	119.35
N2—C7—N1	112.9 (3)	C4—C3—H3A	119.35
N2—C7—C8	122.9 (3)	C3—C4—H4A	120.84
N1—C7—C8	124.0 (3)	C5—C4—H4A	120.84
C9—C8—C13	117.4 (3)	C8—C9—H9A	118.87
C9—C8—C7	117.6 (3)	C10—C9—H9A	118.87
C13—C8—C7	125.0 (3)	C9—C10—H10A	120.82
C10—C9—C8	122.3 (4)	C11—C10—H10A	120.82
C11—C10—C9	118.4 (4)	C11—C12—H12A	120.37
C12—C11—C10	121.7 (3)	C13—C12—H12A	120.37
C12—C11—Cl2	118.9 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···N2^i	0.86	2.06	2.866 (2)	155
N1—H1A···Cl1	0.86	2.79	3.150 (3)	106

Symmetry code: (i) −x+1/2, y−1/2, z.