organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2-[4-(Tri­fluoro­meth­­oxy)phen­yl]-1H-benzimidazole

aDepartment of Studies in Chemistry, Bangalore University, Bangalore 560 001, India
*Correspondence e-mail: noorsb@rediffmail.com

(Received 3 January 2013; accepted 12 January 2013; online 19 January 2013)

In the title compound, C14H9F3N2O, the best planes of the benzimidazole group and benzene ring form a dihedral angle of 26.68 (3)°. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into infinite chains parallel to the c axis. Stacking inter­actions between the benzimidazole groups [centroid–centroid distance = 3.594 (5) Å] assemble the mol­ecules into layers parallel to (100). The trifluoro­methyl group is disordered over three sets of sites with site-occupancy factors of 0.787 (4), 0.107 (7) and 0.106 (7).

Related literature

For therapeutic and medicinal properties of benzimidazole derivatives, see: Chimirri et al. (1991[Chimirri, A., Grasso, S., Monforte, A. M., Monforte, P. & Zappala, M. (1991). Il Farmaco, 46, 925—933.]); Benavides et al. (1995[Benavides, J., Schoemaker, H., Dana, C., Clausture, Y., Delahaye, M., Prouteau, M., Manoury, P., Allen, J. V., Scatton, B., Langer, S. Z. & Arbilla, S. (1995). Arzneim. Forsch. (Drug. Res.), 45, 551—558.]); Ishihara et al. (1994[Ishihara, K., Ichikawa, T., Komuro, Y., Ohara, S. & Hotta, K. (1994). Arzneim. Forsch. (Drug. Res.), 44, 827—830.]); Kubo et al. (1993[Kubo, K., Kohara, Y., Imamia, E., Sugiura, Y., Inada, Y., Furukawa, Y., Nishikawa, K. & Naka, T. (1993). J. Med. Chem. 36, 2182-2195.]). For related structures, see: Jian et al. (2006[Jian, F.-F., Yu, H.-Q., Qiao, Y.-B., Zhao, P.-S. & Xiao, H.-L. (2006). Acta Cryst. E62, o5194-o5195.]); Rashid, Tahir, Yusof et al. (2007[Rashid, N., Tahir, M. K., Yusof, N. M. & Yamin, B. M. (2007). Acta Cryst. E63, o1260-o1261.]); Rashid, Tahir, Kanwal et al. (2007[Rashid, N., Tahir, M. K., Kanwal, S., Yusof, N. M. & Yamin, B. M. (2007). Acta Cryst. E63, o1402-o1403.]).

[Scheme 1]

Experimental

Crystal data
  • C14H9F3N2O

  • Mr = 278.23

  • Monoclinic, P 21 /c

  • a = 14.476 (6) Å

  • b = 9.312 (4) Å

  • c = 9.835 (4) Å

  • β = 108.192 (8)°

  • V = 1259.5 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 296 K

  • 0.18 × 0.16 × 0.16 mm

Data collection
  • Bruker SMART APEX CCD detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1998[Bruker. (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.978, Tmax = 0.980

  • 6284 measured reflections

  • 2209 independent reflections

  • 1333 reflections with I > 2σ(I)

  • Rint = 0.077

Refinement
  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.157

  • S = 1.00

  • 2209 reflections

  • 210 parameters

  • 21 restraints

  • H-atom parameters constrained

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H21⋯N1i 0.86 2.07 2.864 (4) 154
Symmetry code: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 1998[Bruker. (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 1998[Bruker. (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and CAMERON (Watkin et al., 1996[Watkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, University of Oxford, England.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

Benzimidazole and its derivatives are known to exhibit a wide variety of pharmacological activities such as anti-HIV (Chimirri et al., 1991), antihistaminic (Benavides et al., 1995), antiulcer (Ishihara et al., 1994), antihypertensive (Kubo et al., 1993). The benzimidazole and phenyl groups form a dihedral angle of 26.68 (3)°. The bond lengths and angles of the benzimidazole moiety in the title compound are in good agreement with those observed in other benzimidazole derivatives (Jian et al., 2006; Rashid, Tahir, Yusof et al., 2007; Rashid, Tahir, Kanwal et al., 2007). The N1—C8 and N2—C8 distances were found to be 1.338 (5) Å and 1.356 (5) Å, respectively. The trifluoromethyl group is disordered over three sites with occupancy factors 0.787 (4), 0.107 (7) and 0.106 (7). The molecules are linked by intermolecular N—H···N hydrogen bonds to form infinite chains parallel to the c axis. Additionally, the crystal packing is further stabilized by π -π stacking interactions between the benzimidazole groups [interplanar distance 3.594 (5) Å].

Related literature top

For therapeutic and medicinal properties of benzimidazole derivatives, see: Chimirri et al. (1991); Benavides et al. (1995); Ishihara et al. (1994); Kubo et al. (1993). For related structures, see: Jian et al. (2006); Rashid, Tahir, Yusof et al. (2007); Rashid, Tahir, Kanwal et al. (2007).

Experimental top

A mixture of 4-(trifluoromethoxy)benzaldehyde (10 mmol, 0.19 g) and o-phenyldiamine (10 mmol, 0.19 g) in benzene (2 ml) was refluxed for 6 h on a water bath. The reaction mixture was cooled. The solid separated, was filtered and dried (yield: 0.26 g, 75% and m.p. 503–508 K). Pale yellow crystals of the title compound were obtained by slow evaporation from a solution in ethyl acetate.

Refinement top

All H atoms were included in calculated positions, with C—H bond distances of 0.93 Å and N—H = 0.86 Å and refined in a riding model approximation with Uiso(H) = 1.2Ueq(C,N). The trifluoromethyl group is disordered over three sites with the occupancy factors 0.787 (4), 0.107 (7) and 0.106 (7). The atoms of the minor components were refined isotropically with a common displacement parameter for each group. The geometry of the minor components was restrained to that of the major component with the SAME instruction of SHELXL97 (Sheldrick, 2008).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1998); 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, 2012) and CAMERON (Watkin et al., 1996); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.The trifluoromethyl group is disordered over three sites.
[Figure 2] Fig. 2. A view of the intermolecular hydrogen bonds(dotted lines) in the crystal structure of the title compound. H atoms non participating in H-bonding and minor components of the disordered CF3 group were omitted for clarity.
2-[4-(Trifluoromethoxy)phenyl]-1H-benzimidazole top
Crystal data top
C14H9F3N2OF(000) = 568
Mr = 278.23Dx = 1.467 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2209 reflections
a = 14.476 (6) Åθ = 2.6–25.0°
b = 9.312 (4) ŵ = 0.13 mm1
c = 9.835 (4) ÅT = 296 K
β = 108.192 (8)°Block, yellow
V = 1259.5 (9) Å30.18 × 0.16 × 0.16 mm
Z = 4
Data collection top
Bruker SMART APEX CCD detector
diffractometer
2209 independent reflections
Radiation source: fine-focus sealed tube1333 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.077
ω scansθmax = 25.0°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
h = 1715
Tmin = 0.978, Tmax = 0.980k = 811
6284 measured reflectionsl = 1111
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.157H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.0655P)2]
where P = (Fo2 + 2Fc2)/3
2209 reflections(Δ/σ)max = 0.001
210 parametersΔρmax = 0.26 e Å3
21 restraintsΔρmin = 0.22 e Å3
Crystal data top
C14H9F3N2OV = 1259.5 (9) Å3
Mr = 278.23Z = 4
Monoclinic, P21/cMo Kα radiation
a = 14.476 (6) ŵ = 0.13 mm1
b = 9.312 (4) ÅT = 296 K
c = 9.835 (4) Å0.18 × 0.16 × 0.16 mm
β = 108.192 (8)°
Data collection top
Bruker SMART APEX CCD detector
diffractometer
2209 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
1333 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.980Rint = 0.077
6284 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.06421 restraints
wR(F2) = 0.157H-atom parameters constrained
S = 1.00Δρmax = 0.26 e Å3
2209 reflectionsΔρmin = 0.22 e Å3
210 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
C10.3459 (2)0.8348 (3)0.4611 (3)0.0246 (8)
C20.3309 (2)0.9562 (3)0.3748 (3)0.0297 (8)
H20.37860.98570.33590.036*
C30.2445 (2)1.0344 (4)0.3460 (4)0.0361 (9)
H30.23521.11770.29120.043*
C40.1735 (2)0.9856 (4)0.4004 (4)0.0333 (9)
C60.1860 (2)0.8644 (3)0.4854 (3)0.0321 (9)
H60.13680.83320.52060.039*
C70.2734 (2)0.7900 (3)0.5172 (3)0.0284 (8)
H70.28360.70970.57630.034*
C80.4390 (2)0.7578 (3)0.4969 (3)0.0245 (8)
C90.5675 (2)0.6361 (3)0.6072 (3)0.0260 (8)
C100.6411 (2)0.5565 (3)0.7050 (3)0.0316 (9)
H100.63390.52280.79010.038*
C110.7245 (2)0.5305 (3)0.6695 (4)0.0327 (9)
H110.77430.47780.73230.039*
C120.7367 (2)0.5806 (3)0.5422 (3)0.0311 (8)
H120.79460.56240.52330.037*
C130.6639 (2)0.6567 (3)0.4443 (3)0.0277 (8)
H130.67090.68830.35830.033*
C140.5804 (2)0.6840 (3)0.4794 (3)0.0233 (8)
O10.08661 (17)1.0648 (3)0.3804 (3)0.0460 (7)
N10.47847 (18)0.6843 (3)0.6176 (3)0.0272 (7)
N20.49671 (18)0.7606 (3)0.4113 (3)0.0260 (7)
H210.48360.80240.32950.031*
C50.0271 (4)1.0787 (7)0.2470 (6)0.0534 (16)0.787 (4)
F10.0537 (4)1.1368 (8)0.2540 (9)0.0740 (15)0.787 (4)
F20.0616 (3)1.1639 (8)0.1658 (6)0.0954 (17)0.787 (4)
F30.0071 (4)0.9548 (6)0.1788 (7)0.110 (2)0.787 (4)
C510.0312 (14)1.109 (2)0.268 (3)0.047 (6)*0.107 (7)
F110.0580 (16)1.145 (3)0.259 (7)0.047 (6)*0.107 (7)
F210.0781 (14)1.2304 (19)0.261 (3)0.047 (6)*0.107 (7)
F310.030 (3)1.033 (3)0.154 (4)0.047 (6)*0.107 (7)
C520.010 (2)1.062 (3)0.270 (3)0.056 (7)*0.106 (7)
F120.066 (4)1.144 (3)0.251 (8)0.056 (7)*0.106 (7)
F220.0187 (16)0.928 (2)0.282 (3)0.056 (7)*0.106 (7)
F320.037 (4)1.064 (4)0.154 (4)0.056 (7)*0.106 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0277 (18)0.0240 (18)0.0207 (17)0.0013 (14)0.0055 (14)0.0033 (14)
C20.031 (2)0.037 (2)0.0256 (18)0.0045 (15)0.0146 (15)0.0039 (16)
C30.040 (2)0.038 (2)0.033 (2)0.0027 (17)0.0134 (17)0.0087 (17)
C40.030 (2)0.035 (2)0.032 (2)0.0030 (16)0.0069 (16)0.0047 (17)
C60.030 (2)0.033 (2)0.035 (2)0.0056 (15)0.0115 (16)0.0059 (17)
C70.033 (2)0.0275 (19)0.0244 (18)0.0029 (15)0.0087 (15)0.0031 (15)
C80.0320 (19)0.0228 (18)0.0204 (17)0.0048 (14)0.0105 (15)0.0034 (14)
C90.0305 (19)0.0217 (18)0.0248 (18)0.0018 (14)0.0069 (14)0.0029 (14)
C100.043 (2)0.028 (2)0.0243 (19)0.0028 (16)0.0104 (16)0.0006 (15)
C110.038 (2)0.0272 (19)0.030 (2)0.0044 (16)0.0060 (16)0.0005 (16)
C120.032 (2)0.0268 (19)0.034 (2)0.0023 (15)0.0106 (16)0.0014 (16)
C130.036 (2)0.0242 (18)0.0250 (18)0.0006 (15)0.0132 (15)0.0037 (15)
C140.0318 (19)0.0179 (17)0.0206 (17)0.0004 (14)0.0087 (14)0.0005 (14)
O10.0353 (15)0.0582 (18)0.0454 (16)0.0162 (12)0.0137 (13)0.0099 (13)
N10.0327 (16)0.0248 (15)0.0238 (15)0.0002 (12)0.0085 (12)0.0020 (12)
N20.0335 (16)0.0241 (15)0.0207 (14)0.0028 (12)0.0089 (12)0.0042 (12)
C50.038 (3)0.065 (5)0.054 (4)0.012 (3)0.010 (3)0.003 (4)
F10.026 (2)0.084 (3)0.111 (3)0.0205 (17)0.021 (2)0.043 (2)
F20.056 (2)0.154 (5)0.086 (3)0.030 (3)0.034 (2)0.078 (3)
F30.076 (3)0.085 (3)0.116 (4)0.016 (3)0.045 (3)0.042 (3)
Geometric parameters (Å, º) top
C1—C21.390 (4)C11—C121.397 (5)
C1—C71.393 (4)C11—H110.9300
C1—C81.469 (4)C12—C131.380 (4)
C2—C31.397 (4)C12—H120.9300
C2—H20.9300C13—C141.380 (4)
C3—C41.376 (5)C13—H130.9300
C3—H30.9300C14—N21.385 (4)
C4—C61.382 (4)O1—C51.332 (6)
C4—O11.417 (4)N2—H210.8600
C6—C71.391 (4)C5—F11.309 (5)
C6—H60.9300C5—F31.321 (7)
C7—H70.9300C5—F21.329 (8)
C8—N11.334 (4)C51—F111.309 (5)
C8—N21.358 (4)C51—F311.321 (7)
C9—N11.399 (4)C51—F211.329 (8)
C9—C141.400 (4)C52—F121.309 (5)
C9—C101.403 (4)C52—F321.321 (7)
C10—C111.379 (5)C52—F221.329 (8)
C10—H100.9300
C2—C1—C7119.5 (3)C10—C11—H11118.9
C2—C1—C8120.0 (3)C12—C11—H11118.9
C7—C1—C8120.4 (3)C13—C12—C11121.0 (3)
C1—C2—C3120.5 (3)C13—C12—H12119.5
C1—C2—H2119.8C11—C12—H12119.5
C3—C2—H2119.8C14—C13—C12117.2 (3)
C4—C3—C2118.6 (3)C14—C13—H13121.4
C4—C3—H3120.7C12—C13—H13121.4
C2—C3—H3120.7C13—C14—N2132.6 (3)
C3—C4—C6122.1 (3)C13—C14—C9122.6 (3)
C3—C4—O1120.8 (3)N2—C14—C9104.8 (3)
C6—C4—O1116.9 (3)C5—O1—C4117.5 (3)
C4—C6—C7118.7 (3)C8—N1—C9104.3 (3)
C4—C6—H6120.6C8—N2—C14107.8 (3)
C7—C6—H6120.6C8—N2—H21126.1
C6—C7—C1120.4 (3)C14—N2—H21126.1
C6—C7—H7119.8F1—C5—F3109.3 (5)
C1—C7—H7119.8F1—C5—F2107.1 (5)
N1—C8—N2112.7 (3)F3—C5—F2106.3 (6)
N1—C8—C1124.7 (3)F1—C5—O1107.6 (5)
N2—C8—C1122.5 (3)F3—C5—O1112.8 (5)
N1—C9—C14110.4 (3)F2—C5—O1113.6 (5)
N1—C9—C10129.7 (3)F11—C51—F31109.3 (5)
C14—C9—C10119.9 (3)F11—C51—F21107.1 (5)
C11—C10—C9117.1 (3)F31—C51—F21106.3 (6)
C11—C10—H10121.4F12—C52—F32109.3 (5)
C9—C10—H10121.4F12—C52—F22107.1 (5)
C10—C11—C12122.2 (3)F32—C52—F22106.3 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H21···N1i0.862.072.864 (4)154
Symmetry code: (i) x, y+3/2, z1/2.

Experimental details

Crystal data
Chemical formulaC14H9F3N2O
Mr278.23
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)14.476 (6), 9.312 (4), 9.835 (4)
β (°) 108.192 (8)
V3)1259.5 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.13
Crystal size (mm)0.18 × 0.16 × 0.16
Data collection
DiffractometerBruker SMART APEX CCD detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1998)
Tmin, Tmax0.978, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
6284, 2209, 1333
Rint0.077
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.157, 1.00
No. of reflections2209
No. of parameters210
No. of restraints21
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.26, 0.22

Computer programs: SMART (Bruker, 1998), SAINT-Plus (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and CAMERON (Watkin et al., 1996), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H21···N1i0.862.0662.864 (4)154
Symmetry code: (i) x, y+3/2, z1/2.
 

Acknowledgements

NSB is thankful to the University Grants Commission (UGC), India, for financial assistance.

References

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First citationRashid, N., Tahir, M. K., Kanwal, S., Yusof, N. M. & Yamin, B. M. (2007). Acta Cryst. E63, o1402–o1403.  Web of Science CSD CrossRef CAS IUCr Journals
First citationRashid, N., Tahir, M. K., Yusof, N. M. & Yamin, B. M. (2007). Acta Cryst. E63, o1260–o1261.  Web of Science CSD CrossRef CAS IUCr Journals
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First citationWatkin, D. J., Prout, C. K. & Pearce, L. J. (1996). CAMERON. Chemical Crystallography Laboratory, University of Oxford, England.

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