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Acta Crystallogr Sect E Struct Rep Online. 2010 May 1; 66(Pt 5): o1167.
Published online 2010 April 24. doi:  10.1107/S1600536810014613
PMCID: PMC2979132

2-(4-Fluoro­phen­yl)-3-methyl­sulfinyl-5-phenyl-1-benzofuran

Abstract

In the title mol­ecule, C21H15FO2S, the O atom and the methyl group of the methyl­sulfinyl substituent are situated on the opposite sides of the plane through the benzofuran fragment. The benzofuran ring plane makes dihedral angles of 28.63 (6) and 31.55 (5)° with the 4-fluoro­phenyl and phenyl rings, respectively. Weak C—H(...)F and C—H(...)O hydrogen bonds and inter­molecular C—H(...)π inter­actions are present in the crystal structure. The title crystal was refined as an inversion twin with a 0.39 (7):0.61 (7) domain ratio.

Related literature

For the crystal structures of similar 3-alkyl­sulfanyl-2-(4-fluoro­phen­yl)-5-phenyl-1-benzofuran derivatives, see: Choi et al. (2009 [triangle], 2010 [triangle]). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006 [triangle]); Galal et al. (2009 [triangle]); Khan et al. (2005 [triangle]). For natural products with benzofuran rings, see: Akgul & Anil (2003 [triangle]); Soekamto et al. (2003 [triangle]). For hydrogen bonding, see: Desiraju & Steiner (1999 [triangle]).

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Object name is e-66-o1167-scheme1.jpg

Experimental

Crystal data

  • C21H15FO2S
  • M r = 350.39
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1167-efi11.jpg
  • a = 10.148 (2) Å
  • b = 7.117 (1) Å
  • c = 11.991 (2) Å
  • β = 110.047 (2)°
  • V = 813.6 (2) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.22 mm−1
  • T = 173 K
  • 0.40 × 0.40 × 0.25 mm

Data collection

  • Bruker SMART APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.917, T max = 0.947
  • 4812 measured reflections
  • 3226 independent reflections
  • 3065 reflections with I > 2σ(I)
  • R int = 0.019

Refinement

  • R[F 2 > 2σ(F 2)] = 0.032
  • wR(F 2) = 0.086
  • S = 1.06
  • 3226 reflections
  • 228 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.31 e Å−3
  • Δρmin = −0.21 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1308 Friedel pairs
  • Flack parameter: 0.39 (7)

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg, 1998 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810014613/fb2185sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810014613/fb2185Isup2.hkl

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

supplementary crystallographic information

Comment

The compounds with the benzofuran skeleton show significant pharmacological activities such as fungicide (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009) and antimicrobial (Khan et al., 2005) properties. These compounds are common in Nature (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing studies of the effect of the side chain substituents on the solid state structures of 3-alkylsulfanyl-2-(4-fluorophenyl)-5-phenyl-1-benzofuran analogues (Choi et al., 2009, 2010), we report the title crystal structure. The title molecule is depicted in Fig. 1.

The benzofuran ring is essentially planar, with a mean deviation of 0.006 (2) Å from the least-squares plane defined by the nine constituent atoms. In the molecule, the benzofuran plane makes dihedral angles of 28.63 (6) and 31.55 (5)° with the 4-fluorophenyl ring and the phenyl ring, respectively. The molecular packing (Fig. 2) is stabilized by an intermolecular C—H···F hydrogen bond between the methyl H atom and the fluorine (Tab. 1). There are also C—H···O interactions (Tab. 1 and Fig. 2) with geometrical parameters that are on the limit of their acceptance as true weak C—H···O hydrogen bonds (Desiraju & Steiner, 1999). The molecular packing (Fig. 3) is further stabilized by two intermolecular C—H···π-electron ring interactions: The first one between the 4-fluorophenyl H atom and the 5-phenyl ring, and the second one between the 4-fluorophenyl H atom and 4-fluorophenyl ring (Tab. 1).

Experimental

77% 3-chloroperoxybenzoic acid (224 mg, 1.0 mmol) was added in small portions to a stirred solution of 2-(4-fluorophenyl)-3-methylsulfanyl-5-phenyl-1-benzofuran (301 mg, 0.9 mmol) in dichloromethane (30 ml) at 273 K. After having been stirred at room temperature for 4h, the mixture was washed with saturated sodium hydrogencarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (silica gel, hexane–ethyl acetate, 1:1 v/v) to afford the title compound as a colourless solid [yield 80%, m.p. 506–507 K; Rf = 0.59 (hexane–ethyl acetate, 1:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in chloroform at room temperature. The average crystal size was approximately 1.0 × 1.0 × 0.5 mm. (The measured crystal was cut from the larger one.) The crystals are colourless and soluble in polar solvents.

Refinement

All the H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 Å for the aryl H atoms and 0.96 Å for the methyl H atoms, and with Uiso(H) = 1.2Ueq(C) for the aryl H atoms and 1.5Ueq(C) for the methyl H atoms. 1308 Friedel pairs have been used in the refinement.

Figures

Fig. 1.
The title molecule with the atom numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. The H atoms are depicted as small spheres of arbitrary radius.
Fig. 2.
C—H···F and C—H···O interactions (dotted lines) in the crystal structure of the title compound. [Symmetry codes: (i) -x, y-1/2, -z+1; (ii) -x+1, y-1/2, -z+2; (iii) -x+2, y-1/2, -z+2; (v) ...
Fig. 3.
C—H···π-electron ring interactions (dotted lines) in the crystal structure of the title compound. Cg denotes the ring centroids. [Symmetry codes: (iii) -x+2, y-1/2, -z+2; (iv) -x+1, y+1/2, -z+1; (viii) -x+1, y-1/2, ...

Crystal data

C21H15FO2SF(000) = 364
Mr = 350.39Dx = 1.430 Mg m3
Monoclinic, P21Melting point = 506–507 K
Hall symbol: P 2ybMo Kα radiation, λ = 0.71073 Å
a = 10.148 (2) ÅCell parameters from 3710 reflections
b = 7.117 (1) Åθ = 2.3–28.3°
c = 11.991 (2) ŵ = 0.22 mm1
β = 110.047 (2)°T = 173 K
V = 813.6 (2) Å3Block, colourless
Z = 20.40 × 0.40 × 0.25 mm

Data collection

Bruker SMART APEXII CCD diffractometer3226 independent reflections
Radiation source: rotating anode3065 reflections with I > 2σ(I)
graphite multilayerRint = 0.019
Detector resolution: 10.0 pixels mm-1θmax = 27.0°, θmin = 1.8°
[var phi] and ω scansh = −8→12
Absorption correction: multi-scan (SADABS; Bruker, 2009)k = −9→8
Tmin = 0.917, Tmax = 0.947l = −15→14
4812 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.032H-atom parameters constrained
wR(F2) = 0.086w = 1/[σ2(Fo2) + (0.0516P)2 + 0.1094P] where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
3226 reflectionsΔρmax = 0.31 e Å3
228 parametersΔρmin = −0.21 e Å3
1 restraintAbsolute structure: Flack (1983), 1308 Friedel pairs
59 constraintsFlack parameter: 0.39 (7)
Primary atom site location: structure-invariant direct methods

Special details

Experimental. The measured sample has been cut from the larger crystal. The crystals, both the grown ones as well as the cut one, have not been examined under the polarization microscope.
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 > 2sigma(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. The diffractions 1 0 0 and 0 0 1 as well as their equivalents have been excluded from the refinement because their respective intensities significantly differed from the calculated ones.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
S0.55747 (5)0.51643 (8)0.86742 (4)0.03009 (13)
F1.26845 (12)0.4440 (2)1.03910 (11)0.0425 (3)
O10.70363 (13)0.4548 (2)0.60162 (10)0.0280 (3)
O20.44274 (15)0.6590 (2)0.83904 (13)0.0398 (4)
C10.59124 (17)0.4753 (3)0.73449 (15)0.0251 (4)
C20.48587 (19)0.4671 (3)0.61728 (15)0.0257 (4)
C30.33954 (18)0.4703 (3)0.57251 (15)0.0256 (4)
H30.28830.48100.62340.031*
C40.27128 (18)0.4572 (3)0.44981 (15)0.0255 (4)
C50.35234 (19)0.4441 (3)0.37470 (16)0.0286 (4)
H50.30610.43520.29320.034*
C60.4975 (2)0.4439 (3)0.41758 (16)0.0317 (4)
H60.54950.43660.36720.038*
C70.56102 (19)0.4553 (3)0.53979 (16)0.0264 (4)
C80.71883 (19)0.4670 (3)0.72036 (15)0.0255 (4)
C90.86341 (18)0.4633 (3)0.80353 (15)0.0242 (4)
C100.97478 (18)0.5278 (3)0.76948 (16)0.0278 (4)
H100.95660.57450.69320.033*
C111.11179 (18)0.5224 (3)0.84845 (17)0.0317 (4)
H111.18570.56630.82650.038*
C121.13528 (19)0.4503 (3)0.96030 (17)0.0291 (4)
C131.0289 (2)0.3813 (3)0.99652 (17)0.0288 (4)
H131.04840.33141.07220.035*
C140.89299 (19)0.3886 (3)0.91741 (16)0.0268 (4)
H140.82010.34320.94020.032*
C150.11547 (19)0.4540 (3)0.39950 (15)0.0250 (4)
C160.0356 (2)0.3732 (3)0.46221 (16)0.0281 (4)
H160.08060.32310.53730.034*
C17−0.1097 (2)0.3669 (3)0.41369 (17)0.0313 (4)
H17−0.16100.31390.45680.038*
C18−0.1788 (2)0.4392 (3)0.30148 (18)0.0323 (4)
H18−0.27600.43260.26860.039*
C19−0.10197 (19)0.5216 (3)0.23840 (16)0.0315 (4)
H19−0.14780.57180.16350.038*
C200.04378 (18)0.5288 (3)0.28756 (15)0.0277 (4)
H200.09440.58480.24480.033*
C210.4775 (2)0.2943 (4)0.8756 (2)0.0421 (6)
H21A0.44900.29250.94410.063*
H21B0.54380.19520.88170.063*
H21C0.39700.27650.80530.063*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S0.0302 (2)0.0398 (3)0.02136 (19)0.0062 (2)0.01031 (15)−0.0019 (2)
F0.0287 (6)0.0505 (8)0.0447 (7)−0.0009 (6)0.0080 (5)0.0011 (6)
O10.0297 (7)0.0328 (7)0.0243 (6)0.0016 (6)0.0128 (5)0.0010 (6)
O20.0390 (8)0.0470 (10)0.0350 (8)0.0117 (7)0.0148 (7)−0.0033 (7)
C10.0285 (9)0.0257 (11)0.0232 (8)0.0025 (7)0.0116 (7)−0.0012 (7)
C20.0336 (9)0.0226 (10)0.0228 (8)0.0019 (7)0.0120 (7)0.0007 (7)
C30.0306 (9)0.0244 (11)0.0253 (8)0.0003 (7)0.0142 (7)−0.0004 (7)
C40.0306 (9)0.0213 (9)0.0250 (8)−0.0008 (8)0.0100 (7)0.0015 (8)
C50.0361 (10)0.0289 (10)0.0224 (8)−0.0012 (8)0.0122 (7)−0.0009 (8)
C60.0364 (10)0.0369 (11)0.0269 (9)0.0023 (9)0.0173 (8)0.0011 (9)
C70.0292 (9)0.0247 (9)0.0285 (9)0.0011 (8)0.0140 (7)0.0003 (8)
C80.0322 (9)0.0220 (10)0.0253 (8)0.0005 (7)0.0135 (7)0.0017 (7)
C90.0264 (9)0.0198 (9)0.0289 (8)0.0020 (7)0.0129 (7)−0.0005 (8)
C100.0346 (9)0.0241 (9)0.0304 (8)0.0022 (9)0.0184 (7)0.0027 (9)
C110.0311 (9)0.0265 (10)0.0439 (10)−0.0006 (9)0.0211 (8)−0.0002 (10)
C120.0249 (9)0.0264 (10)0.0354 (9)0.0025 (8)0.0094 (7)−0.0021 (9)
C130.0337 (11)0.0249 (10)0.0289 (9)0.0027 (8)0.0121 (8)0.0015 (8)
C140.0292 (10)0.0242 (10)0.0310 (9)0.0007 (7)0.0154 (8)0.0016 (8)
C150.0330 (9)0.0196 (9)0.0237 (8)−0.0035 (8)0.0114 (7)−0.0042 (8)
C160.0374 (11)0.0254 (10)0.0234 (8)−0.0021 (8)0.0126 (8)−0.0002 (8)
C170.0352 (10)0.0285 (11)0.0351 (10)−0.0046 (8)0.0183 (8)−0.0027 (9)
C180.0265 (9)0.0319 (11)0.0385 (10)−0.0017 (8)0.0108 (8)−0.0040 (9)
C190.0358 (9)0.0270 (10)0.0288 (8)0.0016 (9)0.0073 (7)0.0011 (9)
C200.0342 (9)0.0234 (9)0.0273 (8)−0.0040 (9)0.0130 (7)0.0017 (9)
C210.0451 (13)0.0481 (15)0.0405 (12)0.0055 (11)0.0242 (10)0.0131 (11)

Geometric parameters (Å, °)

S—O21.4931 (16)C10—H100.9300
S—C11.7660 (17)C11—C121.379 (3)
S—C211.795 (2)C11—H110.9300
F—C121.359 (2)C12—C131.385 (3)
O1—C81.381 (2)C13—C141.381 (3)
O1—C71.382 (2)C13—H130.9300
C1—C81.364 (2)C14—H140.9300
C1—C21.446 (2)C15—C201.395 (3)
C2—C71.392 (2)C15—C161.404 (3)
C2—C31.395 (2)C16—C171.388 (3)
C3—C41.398 (2)C16—H160.9300
C3—H30.9300C17—C181.386 (3)
C4—C51.416 (2)C17—H170.9300
C4—C151.487 (2)C18—C191.388 (3)
C5—C61.383 (3)C18—H180.9300
C5—H50.9300C19—C201.393 (2)
C6—C71.386 (3)C19—H190.9300
C6—H60.9300C20—H200.9300
C8—C91.464 (2)C21—H21A0.9600
C9—C141.399 (2)C21—H21B0.9600
C9—C101.404 (2)C21—H21C0.9600
C10—C111.389 (2)
O2—S—C1106.52 (9)C12—C11—H11120.9
O2—S—C21106.22 (10)C10—C11—H11120.9
C1—S—C2197.72 (10)F—C12—C11119.20 (16)
C8—O1—C7106.22 (13)F—C12—C13117.85 (18)
C8—C1—C2107.14 (15)C11—C12—C13122.95 (18)
C8—C1—S127.27 (14)C14—C13—C12118.27 (18)
C2—C1—S125.19 (13)C14—C13—H13120.9
C7—C2—C3119.90 (16)C12—C13—H13120.9
C7—C2—C1105.03 (15)C13—C14—C9120.97 (17)
C3—C2—C1135.07 (16)C13—C14—H14119.5
C2—C3—C4118.80 (15)C9—C14—H14119.5
C2—C3—H3120.6C20—C15—C16117.73 (17)
C4—C3—H3120.6C20—C15—C4121.06 (15)
C3—C4—C5119.18 (16)C16—C15—C4121.20 (16)
C3—C4—C15120.16 (15)C17—C16—C15120.94 (18)
C5—C4—C15120.66 (16)C17—C16—H16119.5
C6—C5—C4122.70 (17)C15—C16—H16119.5
C6—C5—H5118.7C18—C17—C16120.43 (18)
C4—C5—H5118.7C18—C17—H17119.8
C5—C6—C7116.31 (16)C16—C17—H17119.8
C5—C6—H6121.8C17—C18—C19119.61 (18)
C7—C6—H6121.8C17—C18—H18120.2
O1—C7—C6126.11 (16)C19—C18—H18120.2
O1—C7—C2110.78 (15)C18—C19—C20119.88 (17)
C6—C7—C2123.10 (17)C18—C19—H19120.1
C1—C8—O1110.83 (15)C20—C19—H19120.1
C1—C8—C9133.51 (16)C19—C20—C15121.40 (17)
O1—C8—C9115.64 (14)C19—C20—H20119.3
C14—C9—C10118.91 (16)C15—C20—H20119.3
C14—C9—C8120.10 (15)S—C21—H21A109.5
C10—C9—C8120.96 (16)S—C21—H21B109.5
C11—C10—C9120.69 (17)H21A—C21—H21B109.5
C11—C10—H10119.7S—C21—H21C109.5
C9—C10—H10119.7H21A—C21—H21C109.5
C12—C11—C10118.19 (16)H21B—C21—H21C109.5
O2—S—C1—C8133.81 (19)C7—O1—C8—C9178.29 (16)
C21—S—C1—C8−116.67 (19)C1—C8—C9—C1427.8 (3)
O2—S—C1—C2−38.02 (19)O1—C8—C9—C14−150.11 (18)
C21—S—C1—C271.50 (18)C1—C8—C9—C10−154.5 (2)
C8—C1—C2—C7−0.3 (2)O1—C8—C9—C1027.6 (3)
S—C1—C2—C7172.91 (16)C14—C9—C10—C11−1.7 (3)
C8—C1—C2—C3−179.7 (2)C8—C9—C10—C11−179.48 (19)
S—C1—C2—C3−6.5 (3)C9—C10—C11—C120.7 (3)
C7—C2—C3—C41.4 (3)C10—C11—C12—F−179.86 (19)
C1—C2—C3—C4−179.3 (2)C10—C11—C12—C130.8 (3)
C2—C3—C4—C5−1.0 (3)F—C12—C13—C14179.42 (18)
C2—C3—C4—C15178.04 (17)C11—C12—C13—C14−1.2 (3)
C3—C4—C5—C6−0.1 (3)C12—C13—C14—C90.1 (3)
C15—C4—C5—C6−179.11 (19)C10—C9—C14—C131.3 (3)
C4—C5—C6—C70.7 (3)C8—C9—C14—C13179.05 (18)
C8—O1—C7—C6−179.6 (2)C3—C4—C15—C20149.0 (2)
C8—O1—C7—C2−0.1 (2)C5—C4—C15—C20−32.0 (3)
C5—C6—C7—O1179.1 (2)C3—C4—C15—C16−31.9 (3)
C5—C6—C7—C2−0.3 (3)C5—C4—C15—C16147.1 (2)
C3—C2—C7—O1179.75 (16)C20—C15—C16—C170.5 (3)
C1—C2—C7—O10.3 (2)C4—C15—C16—C17−178.57 (19)
C3—C2—C7—C6−0.8 (3)C15—C16—C17—C180.6 (3)
C1—C2—C7—C6179.71 (19)C16—C17—C18—C19−1.3 (3)
C2—C1—C8—O10.2 (2)C17—C18—C19—C200.8 (3)
S—C1—C8—O1−172.79 (14)C18—C19—C20—C150.3 (3)
C2—C1—C8—C9−177.7 (2)C16—C15—C20—C19−1.0 (3)
S—C1—C8—C99.2 (3)C4—C15—C20—C19178.14 (19)
C7—O1—C8—C1−0.1 (2)

Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C15–C20 (5-phenyl) and the C9–14 (4-fluorophenyl) rings, respectively.
D—H···AD—HH···AD···AD—H···A
C18—H18···O2i0.932.613.301 (3)131
C21—H21A···O2ii0.962.633.375 (3)135
C21—H21B···Fiii0.962.553.478 (3)164
C10—H10···Cg1iv0.932.863.450 (2)122
C13—H13···Cg2iii0.932.813.417 (2)124

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FB2185).

References

  • Akgul, Y. Y. & Anil, H. (2003). Phytochemistry, 63, 939–943. [PubMed]
  • Aslam, S. N., Stevenson, P. C., Phythian, S. J., Veitch, N. C. & Hall, D. R. (2006). Tetrahedron, 62, 4214–4226.
  • Brandenburg, K. (1998). DIAMOND Crystal Impact GbR, Bonn, Germany.
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