Ethyl 1-sec-butyl-2-(4-chloro-phen-yl)-1H-benzimidazole-5-carboxyl-ate.

In the title compound, C(20)H(21)ClN(2)O(2), the ethyl 1H-benzimidazole-5-carboxyl-ate ring system, excluding the methyl-ene and methyl H atoms, is almost planar, with a maximum deviation of 0.055 (1) Å, and makes a dihedral angle of 40.63 (4)° with the benzene ring. The sec-butyl group is disordered over two positions, with refined site occupancies of 0.855 (4) and 0.145 (4). In the crystal, mol-ecules are linked into chains along [010] via inter-molecular C-H⋯O hydrogen bonds and are further inter-connected by C-H⋯Cl inter-actions into two-dimensional networks parallel to (001). The crystal structure is further consolidated by C-H⋯π inter-actions.

Related literature

For the synthesis of the title compound, see: Arumugam et al. (2010a ▶,b ▶,c ▶). For general background to and the therapeutic properties of benzimidazole derivatives, see: Bonfanti et al. (2008 ▶); Evans et al. (1997 ▶); Hori et al. (2002 ▶); Snow (2007 ▶). For a related structure, see: Eltayeb et al. (2009 ▶). For reference bond lengths, see: Allen et al. (1987 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C20H21ClN2O2

M = 356.84

Monoclinic,

a = 10.4321 (9) Å

b = 12.6218 (12) Å

c = 13.6896 (12) Å

β = 97.043 (3)°

V = 1788.9 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.23 mm−1

T = 100 K

0.45 × 0.34 × 0.10 mm

Data collection

Bruker SMART APEXII DUO CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.904, T max = 0.977

21234 measured reflections

8437 independent reflections

6651 reflections with I > 2σ(I)

R int = 0.038

Refinement

R[F 2 > 2σ(F 2)] = 0.050

wR(F 2) = 0.175

S = 1.09

8437 reflections

248 parameters

H-atom parameters constrained

Δρmax = 0.75 e Å−3

Δρmin = −0.39 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810033945/wn2406sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810033945/wn2406Isup2.hkl

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

C20H21ClN2O2	F(000) = 752
Mr = 356.84	Dx = 1.325 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5929 reflections
a = 10.4321 (9) Å	θ = 2.8–36.1°
b = 12.6218 (12) Å	µ = 0.23 mm−1
c = 13.6896 (12) Å	T = 100 K
β = 97.043 (3)°	Plate, colourless
V = 1788.9 (3) Å3	0.45 × 0.34 × 0.10 mm
Z = 4

Bruker SMART APEXII DUO CCD area-detector diffractometer	8437 independent reflections
Radiation source: fine-focus sealed tube	6651 reflections with I > 2σ(I)
graphite	Rint = 0.038
φ and ω scans	θmax = 36.2°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −17→17
Tmin = 0.904, Tmax = 0.977	k = −14→20
21234 measured reflections	l = −22→22

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.175	H-atom parameters constrained
S = 1.09	w = 1/[σ2(Fo2) + (0.0914P)2 + 0.4364P] where P = (Fo2 + 2Fc2)/3
8437 reflections	(Δ/σ)max < 0.001
248 parameters	Δρmax = 0.75 e Å−3
0 restraints	Δρmin = −0.39 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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	Occ. (<1)
Cl1	1.44482 (3)	−0.12780 (3)	0.05943 (3)	0.02804 (10)
O1	0.66151 (9)	0.53169 (7)	0.09366 (8)	0.02287 (19)
O2	0.49447 (10)	0.47833 (8)	0.17101 (8)	0.0244 (2)
N1	0.97430 (9)	0.22053 (7)	0.11935 (8)	0.01566 (17)
N2	0.88205 (10)	0.08363 (8)	0.19214 (8)	0.01724 (18)
C1	1.08637 (12)	−0.04972 (9)	0.10289 (9)	0.0184 (2)
H1A	1.0056	−0.0819	0.0969	0.022*
C2	1.19323 (13)	−0.10669 (10)	0.08102 (9)	0.0198 (2)
H2A	1.1846	−0.1769	0.0607	0.024*
C3	1.31246 (12)	−0.05767 (10)	0.08982 (9)	0.0193 (2)
C4	1.32851 (12)	0.04663 (10)	0.12105 (10)	0.0204 (2)
H4A	1.4096	0.0782	0.1271	0.025*
C5	1.22138 (12)	0.10309 (9)	0.14312 (9)	0.0186 (2)
H5A	1.2310	0.1730	0.1643	0.022*
C6	1.09949 (11)	0.05585 (9)	0.13384 (8)	0.01582 (18)
C7	0.98702 (11)	0.12116 (9)	0.14997 (8)	0.01543 (18)
C8	0.85402 (10)	0.25092 (8)	0.14249 (8)	0.01417 (17)
C9	0.79079 (11)	0.34784 (9)	0.12560 (8)	0.01504 (18)
H9A	0.8286	0.4032	0.0947	0.018*
C10	0.66963 (11)	0.35881 (8)	0.15650 (8)	0.01520 (18)
C11	0.61175 (11)	0.27463 (9)	0.20282 (9)	0.0176 (2)
H11A	0.5306	0.2846	0.2229	0.021*
C12	0.67240 (12)	0.17741 (9)	0.21918 (9)	0.0187 (2)
H12A	0.6338	0.1219	0.2493	0.022*
C13	0.79468 (11)	0.16691 (9)	0.18806 (8)	0.01594 (19)
C14	0.59808 (11)	0.46053 (9)	0.14271 (9)	0.01683 (19)
C15	0.60047 (14)	0.63413 (10)	0.07588 (11)	0.0256 (3)
H15A	0.6041	0.6740	0.1367	0.031*
H15B	0.5107	0.6256	0.0489	0.031*
C16	0.67404 (16)	0.69051 (12)	0.00368 (13)	0.0320 (3)
H16A	0.6341	0.7577	−0.0131	0.048*
H16B	0.6735	0.6483	−0.0547	0.048*
H16C	0.7615	0.7016	0.0327	0.048*
C17A	0.87973 (15)	−0.01159 (11)	0.25461 (12)	0.0170 (3)	0.855 (4)
H17A	0.9624	−0.0480	0.2532	0.020*	0.855 (4)
C18A	0.87305 (16)	0.02241 (14)	0.36090 (11)	0.0228 (3)	0.855 (4)
H18A	0.7882	0.0516	0.3663	0.027*	0.855 (4)
H18B	0.8847	−0.0393	0.4034	0.027*	0.855 (4)
C19A	0.97501 (17)	0.10445 (16)	0.39550 (12)	0.0268 (4)	0.855 (4)
H19A	0.9705	0.1207	0.4635	0.040*	0.855 (4)
H19B	0.9599	0.1676	0.3568	0.040*	0.855 (4)
H19C	1.0590	0.0768	0.3881	0.040*	0.855 (4)
C20A	0.77336 (17)	−0.08965 (12)	0.21576 (16)	0.0277 (4)	0.855 (4)
H20A	0.7817	−0.1070	0.1486	0.042*	0.855 (4)
H20B	0.6904	−0.0579	0.2194	0.042*	0.855 (4)
H20C	0.7812	−0.1529	0.2549	0.042*	0.855 (4)
C17B	0.9122 (10)	0.0082 (8)	0.2857 (7)	0.0179 (16)*	0.145 (4)
H17B	0.9924	−0.0301	0.2791	0.021*	0.145 (4)
C18B	0.8027 (10)	−0.0706 (8)	0.2733 (8)	0.027 (2)*	0.145 (4)
H18C	0.7234	−0.0335	0.2817	0.032*	0.145 (4)
H18D	0.8175	−0.1225	0.3257	0.032*	0.145 (4)
C19B	0.7823 (14)	−0.1313 (11)	0.1720 (11)	0.039 (3)*	0.145 (4)
H19D	0.7234	−0.1891	0.1764	0.059*	0.145 (4)
H19E	0.8636	−0.1582	0.1569	0.059*	0.145 (4)
H19F	0.7472	−0.0836	0.1210	0.059*	0.145 (4)
C20B	0.9247 (12)	0.0562 (10)	0.3823 (8)	0.027 (2)*	0.145 (4)
H20D	0.9400	0.0021	0.4316	0.040*	0.145 (4)
H20E	0.8466	0.0934	0.3909	0.040*	0.145 (4)
H20F	0.9959	0.1050	0.3886	0.040*	0.145 (4)

	U11	U22	U33	U12	U13	U23
Cl1	0.02775 (17)	0.02678 (16)	0.03220 (17)	0.01538 (12)	0.01408 (13)	0.00528 (12)
O1	0.0225 (4)	0.0148 (4)	0.0334 (5)	0.0082 (3)	0.0119 (4)	0.0077 (3)
O2	0.0204 (4)	0.0219 (4)	0.0331 (5)	0.0080 (3)	0.0115 (4)	0.0027 (4)
N1	0.0143 (4)	0.0123 (3)	0.0216 (4)	0.0030 (3)	0.0068 (3)	0.0023 (3)
N2	0.0176 (4)	0.0122 (4)	0.0236 (4)	0.0040 (3)	0.0091 (3)	0.0050 (3)
C1	0.0196 (5)	0.0148 (4)	0.0209 (5)	0.0035 (4)	0.0035 (4)	0.0002 (4)
C2	0.0244 (5)	0.0156 (4)	0.0200 (5)	0.0062 (4)	0.0052 (4)	−0.0001 (4)
C3	0.0211 (5)	0.0189 (5)	0.0189 (5)	0.0093 (4)	0.0070 (4)	0.0035 (4)
C4	0.0175 (5)	0.0192 (5)	0.0256 (5)	0.0044 (4)	0.0068 (4)	0.0022 (4)
C5	0.0178 (5)	0.0153 (4)	0.0237 (5)	0.0031 (4)	0.0071 (4)	0.0010 (4)
C6	0.0171 (4)	0.0135 (4)	0.0177 (4)	0.0043 (3)	0.0054 (4)	0.0023 (3)
C7	0.0156 (4)	0.0130 (4)	0.0186 (4)	0.0034 (3)	0.0059 (3)	0.0023 (3)
C8	0.0140 (4)	0.0114 (4)	0.0179 (4)	0.0019 (3)	0.0054 (3)	0.0021 (3)
C9	0.0155 (4)	0.0121 (4)	0.0181 (4)	0.0025 (3)	0.0046 (3)	0.0019 (3)
C10	0.0155 (4)	0.0131 (4)	0.0175 (4)	0.0033 (3)	0.0042 (3)	0.0005 (3)
C11	0.0158 (4)	0.0169 (4)	0.0212 (5)	0.0025 (4)	0.0064 (4)	0.0017 (4)
C12	0.0169 (5)	0.0161 (4)	0.0246 (5)	0.0019 (4)	0.0089 (4)	0.0045 (4)
C13	0.0162 (4)	0.0136 (4)	0.0191 (4)	0.0033 (3)	0.0064 (4)	0.0032 (3)
C14	0.0170 (5)	0.0149 (4)	0.0189 (4)	0.0040 (3)	0.0034 (4)	0.0007 (3)
C15	0.0283 (6)	0.0170 (5)	0.0334 (6)	0.0121 (4)	0.0118 (5)	0.0070 (4)
C16	0.0335 (7)	0.0215 (6)	0.0440 (8)	0.0110 (5)	0.0171 (6)	0.0111 (6)
C17A	0.0178 (6)	0.0125 (5)	0.0212 (6)	0.0013 (4)	0.0039 (5)	0.0058 (5)
C18A	0.0219 (7)	0.0279 (7)	0.0197 (6)	0.0051 (6)	0.0064 (5)	0.0090 (5)
C19A	0.0267 (8)	0.0356 (9)	0.0180 (6)	0.0097 (7)	0.0016 (5)	−0.0007 (6)
C20A	0.0229 (7)	0.0157 (6)	0.0456 (11)	−0.0037 (5)	0.0083 (7)	0.0041 (6)

Cl1—C3	1.7332 (12)	C15—C16	1.503 (2)
O1—C14	1.3433 (15)	C15—H15A	0.9700
O1—C15	1.4486 (15)	C15—H15B	0.9700
O2—C14	1.2131 (15)	C16—H16A	0.9600
N1—C7	1.3240 (14)	C16—H16B	0.9600
N1—C8	1.3854 (14)	C16—H16C	0.9600
N2—C7	1.3828 (15)	C17A—C18A	1.527 (2)
N2—C13	1.3879 (14)	C17A—C20A	1.530 (2)
N2—C17A	1.4769 (16)	C17A—H17A	0.9800
N2—C17B	1.595 (9)	C18A—C19A	1.518 (3)
C1—C2	1.3897 (17)	C18A—H18A	0.9700
C1—C6	1.3998 (16)	C18A—H18B	0.9700
C1—H1A	0.9300	C19A—H19A	0.9600
C2—C3	1.3812 (19)	C19A—H19B	0.9600
C2—H2A	0.9300	C19A—H19C	0.9600
C3—C4	1.3879 (18)	C20A—H20A	0.9600
C4—C5	1.3895 (17)	C20A—H20B	0.9600
C4—H4A	0.9300	C20A—H20C	0.9600
C5—C6	1.3960 (17)	C17B—C20B	1.447 (15)
C5—H5A	0.9300	C17B—C18B	1.508 (15)
C6—C7	1.4725 (15)	C17B—H17B	0.9800
C8—C9	1.3956 (15)	C18B—C19B	1.576 (18)
C8—C13	1.4112 (15)	C18B—H18C	0.9700
C9—C10	1.3881 (16)	C18B—H18D	0.9700
C9—H9A	0.9300	C19B—H19D	0.9600
C10—C11	1.4104 (16)	C19B—H19E	0.9600
C10—C14	1.4854 (15)	C19B—H19F	0.9600
C11—C12	1.3863 (16)	C20B—H20D	0.9600
C11—H11A	0.9300	C20B—H20E	0.9600
C12—C13	1.3998 (16)	C20B—H20F	0.9600
C12—H12A	0.9300
C14—O1—C15	116.59 (10)	O1—C15—C16	106.49 (11)
C7—N1—C8	104.38 (9)	O1—C15—H15A	110.4
C7—N2—C13	105.87 (9)	C16—C15—H15A	110.4
C7—N2—C17A	126.20 (10)	O1—C15—H15B	110.4
C13—N2—C17A	125.61 (10)	C16—C15—H15B	110.4
C7—N2—C17B	116.8 (4)	H15A—C15—H15B	108.6
C13—N2—C17B	123.2 (3)	C15—C16—H16A	109.5
C2—C1—C6	120.43 (12)	C15—C16—H16B	109.5
C2—C1—H1A	119.8	H16A—C16—H16B	109.5
C6—C1—H1A	119.8	C15—C16—H16C	109.5
C3—C2—C1	119.14 (11)	H16A—C16—H16C	109.5
C3—C2—H2A	120.4	H16B—C16—H16C	109.5
C1—C2—H2A	120.4	N2—C17A—C18A	109.21 (12)
C2—C3—C4	121.67 (11)	N2—C17A—C20A	112.67 (14)
C2—C3—Cl1	119.06 (10)	C18A—C17A—C20A	113.35 (13)
C4—C3—Cl1	119.26 (10)	N2—C17A—H17A	107.1
C3—C4—C5	118.92 (12)	C18A—C17A—H17A	107.1
C3—C4—H4A	120.5	C20A—C17A—H17A	107.1
C5—C4—H4A	120.5	C19A—C18A—C17A	112.15 (12)
C4—C5—C6	120.60 (11)	C19A—C18A—H18A	109.2
C4—C5—H5A	119.7	C17A—C18A—H18A	109.2
C6—C5—H5A	119.7	C19A—C18A—H18B	109.2
C5—C6—C1	119.22 (10)	C17A—C18A—H18B	109.2
C5—C6—C7	118.75 (10)	H18A—C18A—H18B	107.9
C1—C6—C7	121.88 (11)	C20B—C17B—C18B	111.2 (9)
N1—C7—N2	113.76 (9)	C20B—C17B—N2	118.1 (8)
N1—C7—C6	122.25 (10)	C18B—C17B—N2	103.4 (8)
N2—C7—C6	123.86 (10)	C20B—C17B—H17B	107.9
N1—C8—C9	128.88 (10)	C18B—C17B—H17B	107.9
N1—C8—C13	110.60 (9)	N2—C17B—H17B	107.9
C9—C8—C13	120.52 (10)	C17B—C18B—C19B	116.0 (9)
C10—C9—C8	117.80 (10)	C17B—C18B—H18C	108.3
C10—C9—H9A	121.1	C19B—C18B—H18C	108.3
C8—C9—H9A	121.1	C17B—C18B—H18D	108.3
C9—C10—C11	121.19 (10)	C19B—C18B—H18D	108.3
C9—C10—C14	120.64 (10)	H18C—C18B—H18D	107.4
C11—C10—C14	118.17 (10)	C18B—C19B—H19D	109.5
C12—C11—C10	121.83 (10)	C18B—C19B—H19E	109.5
C12—C11—H11A	119.1	H19D—C19B—H19E	109.5
C10—C11—H11A	119.1	C18B—C19B—H19F	109.5
C11—C12—C13	116.72 (10)	H19D—C19B—H19F	109.5
C11—C12—H12A	121.6	H19E—C19B—H19F	109.5
C13—C12—H12A	121.6	C17B—C20B—H20D	109.5
N2—C13—C12	132.68 (10)	C17B—C20B—H20E	109.5
N2—C13—C8	105.39 (9)	H20D—C20B—H20E	109.5
C12—C13—C8	121.93 (10)	C17B—C20B—H20F	109.5
O2—C14—O1	123.27 (11)	H20D—C20B—H20F	109.5
O2—C14—C10	124.96 (11)	H20E—C20B—H20F	109.5
O1—C14—C10	111.77 (10)
C6—C1—C2—C3	−0.27 (18)	C17B—N2—C13—C12	−41.3 (5)
C1—C2—C3—C4	0.76 (19)	C7—N2—C13—C8	0.12 (13)
C1—C2—C3—Cl1	−178.33 (9)	C17A—N2—C13—C8	163.64 (13)
C2—C3—C4—C5	−0.55 (19)	C17B—N2—C13—C8	138.5 (5)
Cl1—C3—C4—C5	178.54 (10)	C11—C12—C13—N2	179.91 (13)
C3—C4—C5—C6	−0.15 (19)	C11—C12—C13—C8	0.17 (18)
C4—C5—C6—C1	0.63 (18)	N1—C8—C13—N2	−0.11 (13)
C4—C5—C6—C7	−174.93 (11)	C9—C8—C13—N2	179.26 (10)
C2—C1—C6—C5	−0.42 (17)	N1—C8—C13—C12	179.69 (11)
C2—C1—C6—C7	175.00 (11)	C9—C8—C13—C12	−0.94 (18)
C8—N1—C7—N2	0.02 (14)	C15—O1—C14—O2	0.54 (19)
C8—N1—C7—C6	176.15 (11)	C15—O1—C14—C10	179.96 (11)
C13—N2—C7—N1	−0.09 (14)	C9—C10—C14—O2	−176.84 (12)
C17A—N2—C7—N1	−163.48 (13)	C11—C10—C14—O2	2.36 (19)
C17B—N2—C7—N1	−141.6 (4)	C9—C10—C14—O1	3.75 (16)
C13—N2—C7—C6	−176.15 (11)	C11—C10—C14—O1	−177.05 (11)
C17A—N2—C7—C6	20.5 (2)	C14—O1—C15—C16	−168.74 (13)
C17B—N2—C7—C6	42.4 (5)	C7—N2—C17A—C18A	108.23 (14)
C5—C6—C7—N1	38.83 (17)	C13—N2—C17A—C18A	−52.01 (18)
C1—C6—C7—N1	−136.61 (12)	C17B—N2—C17A—C18A	38.7 (9)
C5—C6—C7—N2	−145.43 (12)	C7—N2—C17A—C20A	−124.87 (14)
C1—C6—C7—N2	39.13 (17)	C13—N2—C17A—C20A	74.90 (18)
C7—N1—C8—C9	−179.25 (12)	C17B—N2—C17A—C20A	165.6 (10)
C7—N1—C8—C13	0.06 (13)	N2—C17A—C18A—C19A	−50.27 (16)
N1—C8—C9—C10	−179.71 (11)	C20A—C17A—C18A—C19A	−176.79 (13)
C13—C8—C9—C10	1.04 (17)	C7—N2—C17B—C20B	92.8 (8)
C8—C9—C10—C11	−0.44 (17)	C13—N2—C17B—C20B	−41.5 (10)
C8—C9—C10—C14	178.73 (10)	C17A—N2—C17B—C20B	−145.1 (15)
C9—C10—C11—C12	−0.32 (18)	C7—N2—C17B—C18B	−144.0 (5)
C14—C10—C11—C12	−179.51 (11)	C13—N2—C17B—C18B	81.8 (7)
C10—C11—C12—C13	0.44 (18)	C17A—N2—C17B—C18B	−21.9 (7)
C7—N2—C13—C12	−179.65 (13)	C20B—C17B—C18B—C19B	−178.0 (9)
C17A—N2—C13—C12	−16.1 (2)	N2—C17B—C18B—C19B	54.3 (10)

Cg1 is the centroid of the N1/C7/N2/C13/C8 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12A···O2i	0.93	2.57	3.4994 (16)	174
C16—H16A···Cl1ii	0.96	2.73	3.4651 (17)	134
C19A—H19B···Cg1	0.96	2.71	3.3457 (18)	124

Table 1

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the N1/C7/N2/C13/C8 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C12—H12A⋯O2i	0.93	2.57	3.4994 (16)	174
C16—H16A⋯Cl1ii	0.96	2.73	3.4651 (17)	134
C19A—H19B⋯Cg1	0.96	2.71	3.3457 (18)	124

Symmetry codes: (i) ; (ii) .