2-Meth­oxy-6-(6-methyl-1H-benzimid­azol-2-yl)phenol

In the title mol­ecule, C₁₅H₁₄N₂O₂, the substituted benzene ring forms a dihedral angle of 4.15 (1)° with the benzimidazole ring system. An intra­molecular O—H...N hydrogen bond generates an S(6) ring motif. In the solid state, mol­ecules are linked into chains along the [001] via inter­molecular bifurcated N—H...(O,O) hydrogen bonds, which generate R₁²(5) ring motifs. The crystal packing is also consolidated by C—H...π inter­actions, and π–π stacking inter­actions between the imidazole and substituted benzene rings [centroid–centroid distance = 3.5746 (13) Å]. The methyl group attached to the benzimidazole ring system is disordered over two positions with occupancies of 0.587 (6) and 0.413 (6), suggesting 180° rotational disorder for the benzimidazole group.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.004 Å
• Disorder in main residue
• R factor = 0.054
• wR factor = 0.156
• Data-to-parameter ratio = 11.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1     --  C6      ..       6.68 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C3     --  C4      ..       6.35 su
PLAT432_ALERT_2_C Short Inter X...Y Contact  C14    ..  C15A    ..       3.17 Ang.

Alert level G
PLAT301_ALERT_3_G Note Main Residue  Disorder ....................       5.00 Perc.
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          6
PLAT066_ALERT_1_G Predicted and Reported Transmissions Identical .          ?

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 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
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The synthesis of benzimidazoles has received much attention owing to the varied biological activity such as antidiabetic (Minoura et al., 2004), antimicrobial, antifungal (Pawar et al., 2004), antiviral (Tomei et al., 2003), antiHIV (Rao et al., 2003), and anticancer (Demirayak et al., 2002) properties exhibited by a number of derivatives of these compounds. Previously we reported crystal structures of 4-allyl-2-[1-(5-allyl-2-hydroxy-3-methoxybenzyl)-1H-benzimidazol-2-yl]-6- methoxyphenol (Eltayeb et al., 2007a), 2-(2-methoxynaphthalen-1-yl)-1- [(2-methoxynaphthalen-1-yl)methyl]-1H-benzimidazole (Eltayeb et al., 2007b) and 2-(benzimidazol-2-yl)-6-methoxyphenol (Eltayeb et al., 2007c). Owing to the biological importance of the attached benzimidazole ring system, we report here the single-crystal X-ray diffraction study of 2-methoxy-6-(6-methyl-1H-benzimidazol-2-yl)phenol.

The bond lengths (Allen et al., 1987) and angles in the title molecule (Fig. 1) are normal and are comparable to those observed in a closely related structure (Yeap et al., 2009). The dihedral angle between the C8-C13 and N1/N2/C1-C7 rings is 4.15 (1)°. The molecular structure is stabilized by an intramolecular O1—H1O···N2 hydrogen bond which generates an S(6) ring motif (Bernstein et al., 1995).

In the solid state, the molecules are linked via intermolecular N1—H1N···O1 and N1—H1N···O2 bifurcated donor bonds into chains along the [001] (Fig. 2). These hydrogen bonds form an R₁²(5) ring motif. The crystal packing is consolidated by C—H···π (Table 1) interactions involving the C8-C13 benzene ring, and π–π stacking interactions between the C8—C13 (centroid Cg1) ring at (3/2-x, 1/2-y, z) and the N1/C1/C6/N2/C7 (centroid Cg2) ring at (x, y, z), with a Cg1···Cg2 distance of 3.5746 (13) Å.

Related literature

For the biological activity of benzimidazoles derivatives, see: Minoura et al. (2004); Pawar et al. (2004); Tomei et al. (2003); Rao et al. (2003); Demirayak et al. (2002). For related structures, see: Eltayeb et al. (2007a,b,c); Yeap et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

S2. Experimental

To a solution of 4-methyl-1,2-phenylenediamine (0.244 g, 2 mmol) in ethanol (30 ml) was added 3-methoxysalicylaldehyde (0.604 g, 4 mmol). The mixture was refluxed with stirring for half an hour. The resultant red solution was filtered. The red powder obtained was dissolved in dichloromethane. Crystals suitable for XRD were formed after several days of slow evaporation of solvent at room temperature.

S3. Refinement

Atoms H1O and H1N were located in a difference Fourier map and refined freely. The remaining H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 or 0.96 Å and U_iso(H) = 1.2 or 1.5 U_eq(C). A rotating-group model was applied for the methyl groups. The methyl group attached to the benzimidazole ring system is disordered over two positions with refined site-occupancies of 0.587 (6) and 0.413 (6). The U^ij components of the atom C3 were approximated to isotropic behaviour.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Intramolecular interactions are shown as dashed lines. Both disorder components are shown.
	Fig. 2. The crystal packing of the title compound, viewed along the [110]. Hydrogen bonds are shown as dashed lines. Only the major disorder component is shown.

2-Methoxy-6-(6-methyl-1H-benzimidazol-2-yl)phenol

Crystal data

C15H14N2O2	Dx = 1.344 Mg m^−3
Mr = 254.28	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P42/n	Cell parameters from 9054 reflections
Hall symbol: -P 4bc	θ = 2.2–29.6°
a = 14.4118 (2) Å	µ = 0.09 mm^−1
c = 12.0995 (2) Å	T = 100 K
V = 2513.07 (6) Å^3	Block, yellow
Z = 8	0.35 × 0.27 × 0.24 mm
F(000) = 1072

Data collection

Bruker SMART APEXII CCD area-detector diffractometer	2215 independent reflections
Radiation source: fine-focus sealed tube	1725 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
ϕ and ω scans	θmax = 25.0°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −17→16
Tmin = 0.969, Tmax = 0.978	k = −17→17
28200 measured reflections	l = −14→13

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0696P)^2 + 1.1514P] where P = (Fo^2 + 2Fc^2)/3
2215 reflections	(Δ/σ)max = 0.001
193 parameters	Δρmax = 0.29 e Å^−3
6 restraints	Δρmin = −0.17 e Å^−3

Special details

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 esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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	Occ. (<1)
O1	0.63382 (12)	0.20396 (13)	−0.12954 (12)	0.0575 (5)
H1O	0.632 (2)	0.268 (2)	−0.104 (3)	0.094 (10)*
O2	0.63393 (12)	0.02461 (12)	−0.12218 (13)	0.0641 (5)
N1	0.62805 (13)	0.37806 (15)	0.14723 (17)	0.0556 (5)
H1N	0.6438 (18)	0.3647 (18)	0.219 (3)	0.077 (8)*
N2	0.62434 (13)	0.36357 (13)	−0.03521 (15)	0.0506 (5)
C1	0.62626 (15)	0.46707 (17)	0.1047 (2)	0.0579 (6)
C2	0.62707 (18)	0.5541 (2)	0.1545 (3)	0.0726 (8)
H2	0.6299	0.5608	0.2309	0.087*
C3	0.62340 (18)	0.63115 (19)	0.0839 (3)	0.0753 (8)
H3	0.6235	0.6906	0.1139	0.090*	0.413 (6)
C4	0.6197 (2)	0.6204 (2)	−0.0292 (3)	0.0787 (9)
H4	0.6168	0.6729	−0.0738	0.094*	0.587 (6)
C5	0.62015 (19)	0.53499 (19)	−0.0773 (3)	0.0730 (8)
H5	0.6182	0.5289	−0.1538	0.088*
C6	0.62354 (15)	0.45686 (17)	−0.0092 (2)	0.0540 (6)
C7	0.62715 (14)	0.31865 (16)	0.06068 (17)	0.0469 (6)
C8	0.62766 (14)	0.21826 (16)	0.06973 (17)	0.0456 (5)
C9	0.63060 (14)	0.16508 (16)	−0.02796 (16)	0.0456 (5)
C10	0.63048 (15)	0.06902 (17)	−0.02064 (18)	0.0511 (6)
C11	0.62696 (16)	0.02486 (17)	0.0801 (2)	0.0559 (6)
H11	0.6263	−0.0396	0.0838	0.067*
C12	0.62437 (16)	0.07732 (17)	0.17613 (19)	0.0572 (6)
H12	0.6227	0.0478	0.2444	0.069*
C13	0.62424 (15)	0.17223 (16)	0.17120 (18)	0.0513 (6)
H13	0.6218	0.2065	0.2363	0.062*
C14	0.6320 (2)	−0.07360 (18)	−0.1201 (2)	0.0739 (8)
H14A	0.6353	−0.0970	−0.1942	0.111*
H14B	0.5754	−0.0942	−0.0862	0.111*
H14C	0.6840	−0.0962	−0.0784	0.111*
C15	0.6189 (3)	0.7303 (3)	0.1250 (4)	0.0672 (15)	0.587 (6)
H15A	0.6664	0.7664	0.0896	0.101*	0.587 (6)
H15B	0.6282	0.7314	0.2035	0.101*	0.587 (6)
H15C	0.5592	0.7561	0.1078	0.101*	0.587 (6)
C15A	0.6243 (6)	0.7101 (5)	−0.0739 (9)	0.106 (3)	0.413 (6)
H15D	0.5763	0.7175	−0.1282	0.160*	0.413 (6)
H15E	0.6837	0.7191	−0.1080	0.160*	0.413 (6)
H15F	0.6159	0.7549	−0.0161	0.160*	0.413 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0754 (11)	0.0642 (11)	0.0329 (9)	0.0026 (8)	0.0016 (7)	0.0016 (7)
O2	0.0800 (12)	0.0649 (11)	0.0474 (10)	0.0083 (9)	−0.0050 (8)	−0.0113 (8)
N1	0.0574 (12)	0.0687 (14)	0.0407 (11)	0.0040 (10)	−0.0037 (9)	−0.0075 (10)
N2	0.0537 (12)	0.0567 (12)	0.0415 (11)	0.0009 (9)	0.0024 (8)	0.0063 (9)
C1	0.0444 (13)	0.0568 (15)	0.0725 (17)	0.0022 (10)	0.0038 (11)	−0.0055 (12)
C2	0.0608 (16)	0.079 (2)	0.0781 (18)	0.0009 (13)	0.0067 (14)	−0.0209 (16)
C3	0.0564 (15)	0.0563 (16)	0.113 (2)	−0.0023 (12)	0.0144 (15)	−0.0108 (15)
C4	0.0736 (19)	0.071 (2)	0.092 (2)	−0.0012 (14)	0.0211 (16)	0.0047 (16)
C5	0.0750 (18)	0.0601 (17)	0.0837 (19)	0.0024 (13)	0.0163 (15)	0.0105 (15)
C6	0.0490 (13)	0.0562 (15)	0.0568 (15)	−0.0009 (10)	0.0053 (11)	0.0012 (11)
C7	0.0393 (12)	0.0602 (14)	0.0413 (13)	−0.0005 (10)	−0.0004 (9)	−0.0022 (10)
C8	0.0388 (11)	0.0593 (14)	0.0387 (12)	0.0020 (9)	−0.0018 (9)	0.0024 (10)
C9	0.0405 (12)	0.0641 (15)	0.0323 (11)	0.0027 (10)	0.0007 (9)	0.0040 (10)
C10	0.0476 (13)	0.0619 (15)	0.0438 (13)	0.0049 (10)	−0.0056 (10)	−0.0051 (10)
C11	0.0579 (14)	0.0548 (14)	0.0549 (15)	0.0010 (11)	−0.0065 (11)	0.0047 (11)
C12	0.0632 (15)	0.0655 (16)	0.0429 (13)	0.0008 (12)	−0.0042 (11)	0.0075 (11)
C13	0.0563 (14)	0.0637 (15)	0.0338 (12)	0.0018 (11)	−0.0030 (10)	0.0008 (10)
C14	0.085 (2)	0.0676 (18)	0.0689 (18)	0.0108 (14)	−0.0186 (15)	−0.0187 (14)
C15	0.066 (3)	0.061 (3)	0.074 (3)	0.001 (2)	0.005 (2)	−0.009 (2)
C15A	0.102 (6)	0.056 (5)	0.162 (9)	0.003 (4)	0.001 (6)	0.031 (5)

Geometric parameters (Å, º)

O1—C9	1.352 (2)	C5—H5	0.93
O1—H1O	0.97 (3)	C7—C8	1.451 (3)
O2—C10	1.386 (3)	C8—C13	1.396 (3)
O2—C14	1.416 (3)	C8—C9	1.409 (3)
N1—C7	1.353 (3)	C9—C10	1.387 (3)
N1—C1	1.382 (3)	C10—C11	1.376 (3)
N1—H1N	0.92 (3)	C11—C12	1.387 (3)
N2—C7	1.329 (3)	C11—H11	0.93
N2—C6	1.381 (3)	C12—C13	1.369 (3)
C1—C6	1.387 (4)	C12—H12	0.93
C1—C2	1.392 (4)	C13—H13	0.93
C2—C3	1.402 (4)	C14—H14A	0.96
C2—H2	0.93	C14—H14B	0.96
C3—C4	1.378 (5)	C14—H14C	0.96
C3—C15	1.515 (5)	C15—H15A	0.96
C3—H3	0.93	C15—H15B	0.96
C4—C5	1.362 (4)	C15—H15C	0.96
C4—C15A	1.403 (8)	C15A—H15D	0.96
C4—H4	0.93	C15A—H15E	0.96
C5—C6	1.396 (4)	C15A—H15F	0.96
C9—O1—H1O	95.9 (19)	C13—C8—C7	122.7 (2)
C10—O2—C14	116.42 (19)	C9—C8—C7	118.62 (19)
C7—N1—C1	107.4 (2)	O1—C9—C10	118.15 (19)
C7—N1—H1N	127.0 (17)	O1—C9—C8	122.6 (2)
C1—N1—H1N	123.5 (16)	C10—C9—C8	119.28 (19)
C7—N2—C6	106.02 (19)	C11—C10—O2	125.0 (2)
N1—C1—C6	105.8 (2)	C11—C10—C9	121.2 (2)
N1—C1—C2	132.5 (3)	O2—C10—C9	113.8 (2)
C6—C1—C2	121.8 (3)	C10—C11—C12	119.4 (2)
C1—C2—C3	116.7 (3)	C10—C11—H11	120.3
C1—C2—H2	121.6	C12—C11—H11	120.3
C3—C2—H2	121.6	C13—C12—C11	120.5 (2)
C4—C3—C2	121.2 (3)	C13—C12—H12	119.7
C4—C3—C15	115.5 (3)	C11—C12—H12	119.7
C2—C3—C15	123.3 (3)	C12—C13—C8	120.8 (2)
C4—C3—H3	119.4	C12—C13—H13	119.6
C2—C3—H3	119.4	C8—C13—H13	119.6
C5—C4—C3	121.7 (3)	O2—C14—H14A	109.5
C5—C4—C15A	131.9 (5)	O2—C14—H14B	109.5
C3—C4—C15A	106.1 (5)	H14A—C14—H14B	109.5
C5—C4—H4	119.1	O2—C14—H14C	109.5
C3—C4—H4	119.1	H14A—C14—H14C	109.5
C4—C5—C6	118.5 (3)	H14B—C14—H14C	109.5
C4—C5—H5	120.8	C3—C15—H15A	109.5
C6—C5—H5	120.8	C3—C15—H15B	109.5
N2—C6—C1	109.2 (2)	C3—C15—H15C	109.5
N2—C6—C5	130.7 (2)	C4—C15A—H15D	109.5
C1—C6—C5	120.1 (2)	C4—C15A—H15E	109.5
N2—C7—N1	111.6 (2)	H15D—C15A—H15E	109.5
N2—C7—C8	123.48 (19)	C4—C15A—H15F	109.5
N1—C7—C8	124.9 (2)	H15D—C15A—H15F	109.5
C13—C8—C9	118.7 (2)	H15E—C15A—H15F	109.5
C7—N1—C1—C6	0.5 (2)	C1—N1—C7—N2	−0.4 (2)
C7—N1—C1—C2	−179.3 (2)	C1—N1—C7—C8	−179.45 (19)
N1—C1—C2—C3	−179.2 (2)	N2—C7—C8—C13	−175.5 (2)
C6—C1—C2—C3	1.1 (4)	N1—C7—C8—C13	3.5 (3)
C1—C2—C3—C4	−0.4 (4)	N2—C7—C8—C9	3.7 (3)
C1—C2—C3—C15	176.8 (3)	N1—C7—C8—C9	−177.3 (2)
C2—C3—C4—C5	−0.5 (4)	C13—C8—C9—O1	179.87 (19)
C15—C3—C4—C5	−177.9 (3)	C7—C8—C9—O1	0.6 (3)
C2—C3—C4—C15A	−175.4 (4)	C13—C8—C9—C10	−0.3 (3)
C15—C3—C4—C15A	7.2 (5)	C7—C8—C9—C10	−179.56 (19)
C3—C4—C5—C6	0.6 (4)	C14—O2—C10—C11	1.1 (3)
C15A—C4—C5—C6	174.0 (5)	C14—O2—C10—C9	−178.7 (2)
C7—N2—C6—C1	0.2 (2)	O1—C9—C10—C11	−179.8 (2)
C7—N2—C6—C5	−179.4 (2)	C8—C9—C10—C11	0.4 (3)
N1—C1—C6—N2	−0.4 (3)	O1—C9—C10—O2	0.1 (3)
C2—C1—C6—N2	179.4 (2)	C8—C9—C10—O2	−179.74 (18)
N1—C1—C6—C5	179.3 (2)	O2—C10—C11—C12	179.6 (2)
C2—C1—C6—C5	−0.9 (4)	C9—C10—C11—C12	−0.6 (3)
C4—C5—C6—N2	179.7 (2)	C10—C11—C12—C13	0.7 (3)
C4—C5—C6—C1	0.1 (4)	C11—C12—C13—C8	−0.7 (3)
C6—N2—C7—N1	0.1 (2)	C9—C8—C13—C12	0.4 (3)
C6—N2—C7—C8	179.20 (19)	C7—C8—C13—C12	179.7 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O1^i	0.92 (4)	2.03 (3)	2.919 (3)	164 (2)
N1—H1N···O2^i	0.92 (4)	2.58 (3)	3.168 (3)	123 (2)
O1—H1O···N2	0.97 (3)	1.61 (3)	2.572 (3)	167 (3)
C14—H14B···Cg1^ii	0.96	2.95	3.840 (3)	154

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