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

In the title mol-ecule, C(21)H(24)N(2)O(3), the imidazole ring is essentially planar, with a maxium deviation of 0.015 (1) Å. The dihedral angle between the benzene and imidazole rings is 65.47 (6)°. The crystal packing is stabilized by weak inter-molecular C-H⋯O and C-H⋯N hydrogen bonds, forming zigzag chains along the c axis. The crystal structure is further stabilized by C-H⋯π inter-actions.

Related literature

For background to benzimidazole derivatives, their biological activity and medical applications, see: Orjales et al. (1997 ▶); Andrzejewska et al. (2002 ▶); Garuti et al. (2000 ▶); Lukevics et al. (2001 ▶); Komazin et al. (2003 ▶). For details of hydrogen bonding, see: Jeffrey & Saenger (1991 ▶); Jeffrey (1997 ▶); Scheiner (1997 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C21H24N2O3

M = 352.42

Orthorhombic,

a = 14.3963 (7) Å

b = 8.6206 (5) Å

c = 15.1609 (8) Å

V = 1881.54 (17) Å3

Z = 4

Mo Kα radiation

μ = 0.08 mm−1

T = 100 K

0.53 × 0.42 × 0.27 mm

Data collection

Bruker APEX DUO CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.957, T max = 0.978

17426 measured reflections

4233 independent reflections

3951 reflections with I > 2σ(I)

R int = 0.032

Refinement

R[F 2 > 2σ(F 2)] = 0.037

wR(F 2) = 0.113

S = 1.13

4233 reflections

240 parameters

1 restraint

H-atom parameters constrained

Δρmax = 0.60 e Å−3

Δρmin = −0.57 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/S1600536810007956/wn2378sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810007956/wn2378Isup2.hkl

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

C21H24N2O3	F(000) = 752
Mr = 352.42	Dx = 1.244 Mg m−3
Orthorhombic, Pna21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 6765 reflections
a = 14.3963 (7) Å	θ = 2.7–36.9°
b = 8.6206 (5) Å	µ = 0.08 mm−1
c = 15.1609 (8) Å	T = 100 K
V = 1881.54 (17) Å3	Block, colourless
Z = 4	0.53 × 0.42 × 0.27 mm

Bruker APEX DUO CCD area-detector diffractometer	4233 independent reflections
Radiation source: fine-focus sealed tube	3951 reflections with I > 2σ(I)
graphite	Rint = 0.032
φ and ω scans	θmax = 35.0°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −23→12
Tmin = 0.957, Tmax = 0.978	k = −12→13
17426 measured reflections	l = −24→21

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.113	H-atom parameters constrained
S = 1.13	w = 1/[σ2(Fo2) + (0.0773P)2] where P = (Fo2 + 2Fc2)/3
4233 reflections	(Δ/σ)max = 0.001
240 parameters	Δρmax = 0.60 e Å−3
1 restraint	Δρmin = −0.57 e Å−3

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

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
O1	0.12374 (8)	1.21773 (11)	0.18521 (7)	0.02061 (19)
O2	0.25619 (7)	0.09272 (11)	0.59077 (8)	0.02019 (19)
O3	0.11256 (7)	0.01389 (12)	0.63146 (8)	0.02132 (19)
N1	0.00387 (7)	0.60189 (11)	0.40798 (7)	0.01307 (17)
N2	0.16125 (7)	0.58244 (12)	0.40296 (7)	0.01439 (18)
C1	0.07671 (9)	0.95165 (14)	0.37017 (8)	0.0159 (2)
H1A	0.0560	0.9522	0.4283	0.019*
C2	0.08488 (9)	1.09163 (14)	0.32461 (9)	0.0158 (2)
H2A	0.0694	1.1849	0.3518	0.019*
C3	0.11669 (9)	1.08946 (13)	0.23757 (8)	0.01465 (19)
C4	0.14432 (9)	0.95031 (14)	0.19836 (8)	0.0156 (2)
H4A	0.1685	0.9503	0.1415	0.019*
C5	0.13556 (8)	0.81218 (14)	0.24449 (8)	0.01461 (19)
H5A	0.1541	0.7195	0.2184	0.018*
C6	0.09897 (8)	0.81128 (13)	0.33013 (8)	0.01312 (18)
C7	0.08802 (8)	0.66340 (14)	0.37851 (8)	0.01293 (19)
C8	0.02836 (8)	0.47467 (13)	0.45937 (8)	0.01276 (18)
C9	0.12598 (8)	0.46271 (13)	0.45378 (8)	0.01270 (18)
C10	0.17417 (8)	0.34437 (14)	0.49659 (8)	0.01382 (19)
H10A	0.2384	0.3360	0.4921	0.017*
C11	0.12284 (8)	0.23910 (13)	0.54632 (8)	0.01365 (18)
C12	0.02572 (8)	0.25487 (14)	0.55447 (8)	0.0156 (2)
H12A	−0.0068	0.1845	0.5892	0.019*
C13	−0.02274 (8)	0.37223 (14)	0.51221 (8)	0.0157 (2)
H13A	−0.0867	0.3826	0.5187	0.019*
C14	0.17224 (8)	0.10981 (14)	0.59068 (9)	0.01472 (19)
C15	0.14999 (11)	−0.12009 (16)	0.67719 (10)	0.0227 (2)
H15A	0.1157	−0.1375	0.7314	0.027*
H15B	0.2145	−0.1017	0.6923	0.027*
C16	0.14263 (14)	−0.26002 (18)	0.61893 (12)	0.0300 (3)
H16A	0.1631	−0.3501	0.6507	0.045*
H16B	0.1809	−0.2458	0.5677	0.045*
H16C	0.0792	−0.2738	0.6010	0.045*
C17	−0.09468 (8)	0.64670 (15)	0.38647 (9)	0.0157 (2)
C18	−0.14919 (10)	0.50058 (19)	0.36114 (13)	0.0279 (3)
H18A	−0.1544	0.4337	0.4115	0.042*
H18B	−0.1172	0.4471	0.3146	0.042*
H18C	−0.2101	0.5294	0.3414	0.042*
C19	−0.13666 (11)	0.7233 (2)	0.46773 (11)	0.0290 (3)
H19A	−0.0993	0.8106	0.4846	0.044*
H19B	−0.1386	0.6499	0.5153	0.044*
H19C	−0.1985	0.7578	0.4545	0.044*
C20	−0.10132 (11)	0.7557 (2)	0.30761 (12)	0.0305 (4)
H20A	−0.0752	0.8545	0.3229	0.046*
H20B	−0.1653	0.7688	0.2914	0.046*
H20C	−0.0677	0.7124	0.2588	0.046*
C21	0.09176 (12)	1.36157 (16)	0.22065 (10)	0.0232 (3)
H21A	0.0965	1.4409	0.1765	0.035*
H21B	0.1291	1.3894	0.2707	0.035*
H21C	0.0281	1.3511	0.2387	0.035*

	U11	U22	U33	U12	U13	U23
O1	0.0309 (5)	0.0144 (4)	0.0165 (4)	−0.0019 (3)	0.0026 (4)	0.0018 (3)
O2	0.0146 (4)	0.0221 (4)	0.0239 (4)	0.0031 (3)	−0.0012 (3)	0.0034 (4)
O3	0.0189 (4)	0.0182 (4)	0.0269 (5)	0.0009 (3)	0.0004 (4)	0.0079 (4)
N1	0.0101 (4)	0.0151 (4)	0.0141 (4)	0.0004 (3)	0.0000 (3)	0.0013 (3)
N2	0.0117 (4)	0.0141 (4)	0.0174 (4)	−0.0014 (3)	0.0000 (3)	0.0012 (3)
C1	0.0196 (5)	0.0144 (5)	0.0138 (5)	−0.0004 (4)	0.0016 (4)	−0.0007 (4)
C2	0.0195 (5)	0.0135 (5)	0.0145 (5)	−0.0007 (4)	0.0013 (4)	−0.0010 (4)
C3	0.0165 (5)	0.0137 (4)	0.0137 (5)	−0.0022 (4)	−0.0007 (4)	−0.0003 (4)
C4	0.0172 (5)	0.0162 (5)	0.0134 (5)	−0.0025 (4)	0.0015 (4)	−0.0012 (4)
C5	0.0140 (4)	0.0142 (4)	0.0156 (5)	−0.0008 (4)	0.0012 (4)	−0.0019 (4)
C6	0.0126 (4)	0.0127 (4)	0.0140 (4)	−0.0014 (3)	−0.0001 (4)	0.0000 (4)
C7	0.0114 (4)	0.0134 (4)	0.0140 (5)	−0.0009 (3)	−0.0008 (3)	−0.0013 (4)
C8	0.0105 (4)	0.0142 (4)	0.0136 (4)	−0.0001 (3)	0.0007 (3)	0.0006 (4)
C9	0.0102 (4)	0.0130 (4)	0.0149 (4)	−0.0006 (3)	−0.0001 (3)	0.0000 (3)
C10	0.0101 (4)	0.0142 (4)	0.0172 (5)	0.0002 (3)	−0.0010 (4)	−0.0003 (4)
C11	0.0128 (4)	0.0140 (4)	0.0142 (4)	0.0012 (3)	−0.0004 (4)	0.0000 (4)
C12	0.0127 (4)	0.0170 (5)	0.0170 (5)	0.0005 (4)	0.0017 (4)	0.0030 (4)
C13	0.0113 (4)	0.0181 (5)	0.0177 (5)	0.0007 (4)	0.0016 (4)	0.0028 (4)
C14	0.0151 (5)	0.0143 (4)	0.0147 (5)	0.0008 (3)	−0.0012 (4)	−0.0005 (4)
C15	0.0261 (6)	0.0183 (5)	0.0236 (6)	0.0020 (5)	−0.0020 (5)	0.0058 (5)
C16	0.0397 (8)	0.0215 (6)	0.0288 (7)	0.0028 (6)	0.0070 (6)	−0.0002 (5)
C17	0.0101 (4)	0.0204 (5)	0.0165 (5)	0.0025 (4)	−0.0005 (4)	0.0039 (4)
C18	0.0166 (5)	0.0265 (6)	0.0407 (8)	−0.0035 (5)	−0.0102 (5)	0.0018 (6)
C19	0.0214 (6)	0.0409 (8)	0.0248 (7)	0.0142 (6)	0.0012 (5)	−0.0047 (6)
C20	0.0176 (6)	0.0428 (9)	0.0310 (8)	−0.0059 (6)	−0.0073 (5)	0.0231 (7)
C21	0.0339 (7)	0.0139 (5)	0.0220 (6)	0.0002 (5)	0.0013 (5)	0.0024 (4)

O1—C3	1.3649 (15)	C11—C12	1.4102 (16)
O1—C21	1.4277 (17)	C11—C14	1.4833 (16)
O2—C14	1.2174 (15)	C12—C13	1.3860 (16)
O3—C14	1.3432 (16)	C12—H12A	0.9300
O3—C15	1.4509 (16)	C13—H13A	0.9300
N1—C8	1.3908 (15)	C15—C16	1.499 (2)
N1—C7	1.3958 (15)	C15—H15A	0.9700
N1—C17	1.5061 (15)	C15—H15B	0.9700
N2—C7	1.3176 (15)	C16—H16A	0.9600
N2—C9	1.3845 (15)	C16—H16B	0.9600
C1—C6	1.3912 (16)	C16—H16C	0.9600
C1—C2	1.3954 (17)	C17—C19	1.523 (2)
C1—H1A	0.9300	C17—C20	1.5236 (19)
C2—C3	1.3970 (18)	C17—C18	1.5330 (19)
C2—H2A	0.9300	C18—H18A	0.9600
C3—C4	1.3966 (17)	C18—H18B	0.9600
C4—C5	1.3868 (16)	C18—H18C	0.9600
C4—H4A	0.9300	C19—H19A	0.9600
C5—C6	1.4011 (17)	C19—H19B	0.9600
C5—H5A	0.9300	C19—H19C	0.9600
C6—C7	1.4792 (16)	C20—H20A	0.9600
C8—C13	1.4010 (16)	C20—H20B	0.9600
C8—C9	1.4117 (15)	C20—H20C	0.9600
C9—C10	1.3941 (16)	C21—H21A	0.9600
C10—C11	1.3921 (16)	C21—H21B	0.9600
C10—H10A	0.9300	C21—H21C	0.9600
C3—O1—C21	117.44 (11)	O2—C14—O3	124.05 (11)
C14—O3—C15	118.20 (11)	O2—C14—C11	124.57 (11)
C8—N1—C7	105.00 (9)	O3—C14—C11	111.38 (10)
C8—N1—C17	124.22 (9)	O3—C15—C16	109.43 (13)
C7—N1—C17	130.60 (10)	O3—C15—H15A	109.8
C7—N2—C9	104.95 (10)	C16—C15—H15A	109.8
C6—C1—C2	121.12 (11)	O3—C15—H15B	109.8
C6—C1—H1A	119.4	C16—C15—H15B	109.8
C2—C1—H1A	119.4	H15A—C15—H15B	108.2
C1—C2—C3	118.93 (11)	C15—C16—H16A	109.5
C1—C2—H2A	120.5	C15—C16—H16B	109.5
C3—C2—H2A	120.5	H16A—C16—H16B	109.5
O1—C3—C4	115.29 (11)	C15—C16—H16C	109.5
O1—C3—C2	124.26 (11)	H16A—C16—H16C	109.5
C4—C3—C2	120.46 (11)	H16B—C16—H16C	109.5
C5—C4—C3	119.80 (11)	N1—C17—C19	108.05 (11)
C5—C4—H4A	120.1	N1—C17—C20	112.78 (10)
C3—C4—H4A	120.1	C19—C17—C20	110.03 (13)
C4—C5—C6	120.42 (11)	N1—C17—C18	109.01 (10)
C4—C5—H5A	119.8	C19—C17—C18	110.85 (13)
C6—C5—H5A	119.8	C20—C17—C18	106.14 (12)
C1—C6—C5	119.08 (11)	C17—C18—H18A	109.5
C1—C6—C7	120.58 (10)	C17—C18—H18B	109.5
C5—C6—C7	120.29 (10)	H18A—C18—H18B	109.5
N2—C7—N1	113.78 (10)	C17—C18—H18C	109.5
N2—C7—C6	120.71 (10)	H18A—C18—H18C	109.5
N1—C7—C6	125.36 (10)	H18B—C18—H18C	109.5
N1—C8—C13	133.18 (10)	C17—C19—H19A	109.5
N1—C8—C9	106.04 (10)	C17—C19—H19B	109.5
C13—C8—C9	120.74 (10)	H19A—C19—H19B	109.5
N2—C9—C10	128.47 (10)	C17—C19—H19C	109.5
N2—C9—C8	110.13 (10)	H19A—C19—H19C	109.5
C10—C9—C8	121.39 (10)	H19B—C19—H19C	109.5
C11—C10—C9	117.71 (10)	C17—C20—H20A	109.5
C11—C10—H10A	121.1	C17—C20—H20B	109.5
C9—C10—H10A	121.1	H20A—C20—H20B	109.5
C10—C11—C12	120.73 (10)	C17—C20—H20C	109.5
C10—C11—C14	118.74 (10)	H20A—C20—H20C	109.5
C12—C11—C14	120.53 (10)	H20B—C20—H20C	109.5
C13—C12—C11	121.94 (11)	O1—C21—H21A	109.5
C13—C12—H12A	119.0	O1—C21—H21B	109.5
C11—C12—H12A	119.0	H21A—C21—H21B	109.5
C12—C13—C8	117.39 (10)	O1—C21—H21C	109.5
C12—C13—H13A	121.3	H21A—C21—H21C	109.5
C8—C13—H13A	121.3	H21B—C21—H21C	109.5
C6—C1—C2—C3	−0.48 (19)	C7—N2—C9—C8	−0.18 (13)
C21—O1—C3—C4	176.78 (12)	N1—C8—C9—N2	2.09 (13)
C21—O1—C3—C2	−3.48 (19)	C13—C8—C9—N2	−175.77 (11)
C1—C2—C3—O1	177.04 (12)	N1—C8—C9—C10	−178.71 (11)
C1—C2—C3—C4	−3.22 (18)	C13—C8—C9—C10	3.43 (18)
O1—C3—C4—C5	−176.84 (11)	N2—C9—C10—C11	178.14 (12)
C2—C3—C4—C5	3.40 (18)	C8—C9—C10—C11	−0.90 (18)
C3—C4—C5—C6	0.13 (18)	C9—C10—C11—C12	−1.53 (18)
C2—C1—C6—C5	3.95 (18)	C9—C10—C11—C14	178.49 (11)
C2—C1—C6—C7	−178.63 (11)	C10—C11—C12—C13	1.53 (19)
C4—C5—C6—C1	−3.76 (17)	C14—C11—C12—C13	−178.48 (12)
C4—C5—C6—C7	178.81 (11)	C11—C12—C13—C8	0.94 (19)
C9—N2—C7—N1	−1.88 (14)	N1—C8—C13—C12	179.47 (12)
C9—N2—C7—C6	173.81 (11)	C9—C8—C13—C12	−3.35 (18)
C8—N1—C7—N2	3.19 (14)	C15—O3—C14—O2	−1.2 (2)
C17—N1—C7—N2	−172.05 (11)	C15—O3—C14—C11	179.23 (11)
C8—N1—C7—C6	−172.26 (11)	C10—C11—C14—O2	4.03 (19)
C17—N1—C7—C6	12.49 (19)	C12—C11—C14—O2	−175.95 (13)
C1—C6—C7—N2	−110.78 (14)	C10—C11—C14—O3	−176.36 (11)
C5—C6—C7—N2	66.61 (15)	C12—C11—C14—O3	3.65 (16)
C1—C6—C7—N1	64.39 (16)	C14—O3—C15—C16	−97.76 (15)
C5—C6—C7—N1	−118.22 (13)	C8—N1—C17—C19	76.40 (15)
C7—N1—C8—C13	174.46 (13)	C7—N1—C17—C19	−109.15 (15)
C17—N1—C8—C13	−9.9 (2)	C8—N1—C17—C20	−161.76 (13)
C7—N1—C8—C9	−3.02 (12)	C7—N1—C17—C20	12.69 (19)
C17—N1—C8—C9	172.61 (11)	C8—N1—C17—C18	−44.15 (16)
C7—N2—C9—C10	−179.31 (12)	C7—N1—C17—C18	130.30 (14)

Cg1, Cg2 and Cg3 are the centroids of the rings N1,N2,C7–C9 and C1–C6 and C8–C13, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5A···O2i	0.93	2.57	3.3822 (16)	146
C13—H13A···O2ii	0.93	2.52	3.4116 (16)	160
C19—H19C···N2iii	0.96	2.57	3.4976 (19)	164
C2—H2A···Cg3iv	0.93	2.75	3.5594 (14)	146
C18—H18C···Cg2v	0.96	2.74	3.6878 (16)	168
C21—H21B···Cg1iv	0.96	2.78	3.4703 (16)	130

Table 1

Hydrogen-bond geometry (Å, °)

Cg1, Cg2 and Cg3 are the centroids of the rings N1,N2,C7–C9 and C1–C6 and C8–C13, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5A⋯O2i	0.93	2.57	3.3822 (16)	146
C13—H13A⋯O2ii	0.93	2.52	3.4116 (16)	160
C19—H19C⋯N2iii	0.96	2.57	3.4976 (19)	164
C2—H2A⋯Cg3iv	0.93	2.75	3.5594 (14)	146
C18—H18C⋯Cg2v	0.96	2.74	3.6878 (16)	168
C21—H21B⋯Cg1iv	0.96	2.78	3.4703 (16)	130

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .