organic compounds
3-(4-Fluorophenylsulfinyl)-2,5-dimethyl-1-benzofuran
aDepartment of Chemistry, Dongeui University, San 24 Kaya-dong Busanjin-gu, Busan 614-714, Republic of Korea, and bDepartment of Chemistry, Pukyong National University, 599-1 Daeyeon 3-dong, Nam-gu, Busan 608-737, Republic of Korea
*Correspondence e-mail: uklee@pknu.ac.kr
In the title compound, C16H13FO2S, the O atom and the 4-fluorophenyl group of the 4-fluorophenylsulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment; the 4-fluorophenyl ring is nearly perpendicular to this plane, making a dihedral angle of 87.41 (3). The exhibits a weak intermolecular C—H⋯O hydrogen bond.
Related literature
For the crystal structures of similar 2-methyl-3-phenylsulfinyl-1-benzofuran derivatives, see: Choi et al. (2007, 2008a,b). For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006); Galal et al. (2009); Khan et al. (2005). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97.
Supporting information
10.1107/S1600536810003740/fk2012sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810003740/fk2012Isup2.hkl
77% 3-Chloroperoxybenzoic acid (291 mg, 1.3 mmol) was added in small portions to a stirred solution of 3-(4-fluorophenylsulfanyl)-2,5-dimethyl-1-benzofuran (326 mg, 1.2 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 3h, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated in vacuum. The residue was purified by
(hexane-ethyl acetate, 1:1 v/v) to afford the title compound as a colorless solid [yield 80%, m.p. 420-421 K; Rf = 0.69 (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 ethyl acetate at room temperature.All H atoms were positioned geometrically and refined using a riding model, with C–H = 0.95 Å for aryl and 0.98 Å for methyl H atoms. Uiso(H) = 1.2Ueq (C) for aryl and 1.5Ueq(C) for methyl H atoms.
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C16H13FO2S | F(000) = 600 |
Mr = 288.32 | Dx = 1.416 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 9959 reflections |
a = 11.3951 (5) Å | θ = 2.5–27.6° |
b = 6.1223 (3) Å | µ = 0.25 mm−1 |
c = 19.6899 (9) Å | T = 173 K |
β = 100.155 (2)° | Block, colourless |
V = 1352.13 (11) Å3 | 0.30 × 0.30 × 0.21 mm |
Z = 4 |
Bruker SMART APEXII CCD diffractometer | 3115 independent reflections |
Radiation source: Rotating Anode | 2830 reflections with I > 2σ(I) |
Bruker HELIOS graded multilayer optics monochromator | Rint = 0.032 |
Detector resolution: 10.0 pixels mm-1 | θmax = 27.6°, θmin = 1.8° |
ϕ and ω scans | h = −14→14 |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | k = −7→7 |
Tmin = 0.645, Tmax = 0.746 | l = −25→25 |
22996 measured reflections |
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)] = 0.035 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0508P)2 + 0.5136P] where P = (Fo2 + 2Fc2)/3 |
3115 reflections | (Δ/σ)max < 0.001 |
183 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.32 e Å−3 |
C16H13FO2S | V = 1352.13 (11) Å3 |
Mr = 288.32 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.3951 (5) Å | µ = 0.25 mm−1 |
b = 6.1223 (3) Å | T = 173 K |
c = 19.6899 (9) Å | 0.30 × 0.30 × 0.21 mm |
β = 100.155 (2)° |
Bruker SMART APEXII CCD diffractometer | 3115 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2830 reflections with I > 2σ(I) |
Tmin = 0.645, Tmax = 0.746 | Rint = 0.032 |
22996 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.099 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.30 e Å−3 |
3115 reflections | Δρmin = −0.32 e Å−3 |
183 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
S | 0.93298 (3) | 0.31885 (6) | 0.605178 (18) | 0.03074 (12) | |
F1 | 0.72777 (10) | 0.51180 (19) | 0.31715 (5) | 0.0556 (3) | |
O1 | 0.68994 (9) | 0.46191 (17) | 0.71689 (5) | 0.0346 (2) | |
O2 | 0.96804 (10) | 0.08380 (18) | 0.60734 (6) | 0.0410 (3) | |
C1 | 0.80592 (12) | 0.3425 (2) | 0.64361 (7) | 0.0277 (3) | |
C2 | 0.70234 (11) | 0.2027 (2) | 0.63519 (7) | 0.0262 (3) | |
C3 | 0.66200 (12) | 0.0220 (2) | 0.59513 (7) | 0.0299 (3) | |
H3 | 0.7071 | −0.0342 | 0.5628 | 0.036* | |
C4 | 0.55514 (12) | −0.0758 (2) | 0.60278 (7) | 0.0320 (3) | |
C5 | 0.48975 (13) | 0.0120 (3) | 0.65052 (7) | 0.0358 (3) | |
H5 | 0.4167 | −0.0556 | 0.6554 | 0.043* | |
C6 | 0.52732 (13) | 0.1926 (3) | 0.69067 (8) | 0.0369 (3) | |
H6 | 0.4820 | 0.2508 | 0.7225 | 0.044* | |
C7 | 0.63433 (12) | 0.2835 (2) | 0.68184 (7) | 0.0291 (3) | |
C8 | 0.79456 (12) | 0.4921 (2) | 0.69286 (7) | 0.0310 (3) | |
C9 | 0.51060 (15) | −0.2747 (3) | 0.56091 (9) | 0.0433 (4) | |
H9A | 0.5564 | −0.2937 | 0.5236 | 0.065* | |
H9B | 0.4260 | −0.2558 | 0.5412 | 0.065* | |
H9C | 0.5204 | −0.4041 | 0.5907 | 0.065* | |
C10 | 0.87069 (16) | 0.6753 (3) | 0.72348 (8) | 0.0419 (4) | |
H10A | 0.9421 | 0.6830 | 0.7022 | 0.063* | |
H10B | 0.8942 | 0.6518 | 0.7733 | 0.063* | |
H10C | 0.8262 | 0.8126 | 0.7153 | 0.063* | |
C11 | 0.86493 (11) | 0.3744 (2) | 0.51764 (7) | 0.0266 (3) | |
C12 | 0.86759 (12) | 0.2162 (2) | 0.46786 (7) | 0.0305 (3) | |
H12 | 0.9008 | 0.0765 | 0.4804 | 0.037* | |
C13 | 0.82143 (13) | 0.2629 (3) | 0.39942 (8) | 0.0355 (3) | |
H13 | 0.8227 | 0.1568 | 0.3644 | 0.043* | |
C14 | 0.77397 (13) | 0.4659 (3) | 0.38377 (8) | 0.0364 (3) | |
C15 | 0.77240 (14) | 0.6277 (3) | 0.43241 (9) | 0.0391 (3) | |
H15 | 0.7392 | 0.7672 | 0.4196 | 0.047* | |
C16 | 0.82041 (13) | 0.5810 (2) | 0.50024 (8) | 0.0348 (3) | |
H16 | 0.8228 | 0.6901 | 0.5348 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S | 0.02162 (18) | 0.0348 (2) | 0.0361 (2) | 0.00162 (12) | 0.00577 (13) | −0.00400 (13) |
F1 | 0.0606 (6) | 0.0669 (7) | 0.0382 (5) | 0.0008 (5) | 0.0062 (5) | 0.0120 (5) |
O1 | 0.0392 (5) | 0.0384 (5) | 0.0284 (5) | −0.0003 (4) | 0.0118 (4) | −0.0062 (4) |
O2 | 0.0384 (6) | 0.0412 (6) | 0.0443 (6) | 0.0170 (5) | 0.0095 (5) | 0.0035 (5) |
C1 | 0.0259 (6) | 0.0283 (6) | 0.0291 (6) | 0.0017 (5) | 0.0055 (5) | −0.0020 (5) |
C2 | 0.0242 (6) | 0.0276 (6) | 0.0271 (6) | 0.0043 (5) | 0.0051 (5) | 0.0031 (5) |
C3 | 0.0277 (6) | 0.0284 (6) | 0.0341 (7) | 0.0034 (5) | 0.0072 (5) | −0.0016 (5) |
C4 | 0.0297 (7) | 0.0301 (7) | 0.0348 (7) | 0.0004 (5) | 0.0021 (5) | 0.0047 (5) |
C5 | 0.0285 (7) | 0.0438 (8) | 0.0358 (7) | −0.0036 (6) | 0.0076 (6) | 0.0081 (6) |
C6 | 0.0342 (8) | 0.0477 (9) | 0.0319 (7) | 0.0024 (6) | 0.0140 (6) | 0.0021 (6) |
C7 | 0.0319 (7) | 0.0316 (7) | 0.0245 (6) | 0.0029 (5) | 0.0064 (5) | 0.0007 (5) |
C8 | 0.0327 (7) | 0.0332 (7) | 0.0270 (6) | 0.0017 (5) | 0.0045 (5) | −0.0007 (5) |
C9 | 0.0394 (8) | 0.0358 (8) | 0.0532 (9) | −0.0082 (6) | 0.0044 (7) | −0.0019 (7) |
C10 | 0.0495 (9) | 0.0397 (8) | 0.0359 (8) | −0.0069 (7) | 0.0057 (7) | −0.0108 (6) |
C11 | 0.0204 (6) | 0.0265 (6) | 0.0350 (7) | −0.0017 (5) | 0.0106 (5) | −0.0012 (5) |
C12 | 0.0256 (6) | 0.0258 (6) | 0.0414 (7) | 0.0004 (5) | 0.0090 (5) | −0.0041 (5) |
C13 | 0.0312 (7) | 0.0388 (7) | 0.0381 (8) | −0.0038 (6) | 0.0110 (6) | −0.0091 (6) |
C14 | 0.0309 (7) | 0.0432 (8) | 0.0364 (7) | −0.0050 (6) | 0.0097 (6) | 0.0058 (6) |
C15 | 0.0397 (8) | 0.0295 (7) | 0.0497 (9) | 0.0032 (6) | 0.0125 (7) | 0.0077 (6) |
C16 | 0.0362 (7) | 0.0269 (7) | 0.0436 (8) | 0.0026 (5) | 0.0135 (6) | −0.0036 (6) |
S—O2 | 1.4921 (11) | C8—C10 | 1.480 (2) |
S—C1 | 1.7540 (13) | C9—H9A | 0.9800 |
S—C11 | 1.7935 (14) | C9—H9B | 0.9800 |
F1—C14 | 1.3540 (18) | C9—H9C | 0.9800 |
O1—C8 | 1.3705 (17) | C10—H10A | 0.9800 |
O1—C7 | 1.3846 (17) | C10—H10B | 0.9800 |
C1—C8 | 1.3567 (18) | C10—H10C | 0.9800 |
C1—C2 | 1.4434 (18) | C11—C12 | 1.3824 (19) |
C2—C3 | 1.3892 (19) | C11—C16 | 1.3830 (19) |
C2—C7 | 1.3927 (18) | C12—C13 | 1.387 (2) |
C3—C4 | 1.3886 (19) | C12—H12 | 0.9500 |
C3—H3 | 0.9500 | C13—C14 | 1.369 (2) |
C4—C5 | 1.405 (2) | C13—H13 | 0.9500 |
C4—C9 | 1.508 (2) | C14—C15 | 1.380 (2) |
C5—C6 | 1.383 (2) | C15—C16 | 1.381 (2) |
C5—H5 | 0.9500 | C15—H15 | 0.9500 |
C6—C7 | 1.379 (2) | C16—H16 | 0.9500 |
C6—H6 | 0.9500 | ||
O2—S—C1 | 107.72 (7) | C4—C9—H9B | 109.5 |
O2—S—C11 | 106.18 (6) | H9A—C9—H9B | 109.5 |
C1—S—C11 | 98.57 (6) | C4—C9—H9C | 109.5 |
C8—O1—C7 | 106.49 (10) | H9A—C9—H9C | 109.5 |
C8—C1—C2 | 107.65 (12) | H9B—C9—H9C | 109.5 |
C8—C1—S | 123.65 (11) | C8—C10—H10A | 109.5 |
C2—C1—S | 128.47 (10) | C8—C10—H10B | 109.5 |
C3—C2—C7 | 119.36 (12) | H10A—C10—H10B | 109.5 |
C3—C2—C1 | 136.00 (12) | C8—C10—H10C | 109.5 |
C7—C2—C1 | 104.64 (12) | H10A—C10—H10C | 109.5 |
C4—C3—C2 | 119.37 (12) | H10B—C10—H10C | 109.5 |
C4—C3—H3 | 120.3 | C12—C11—C16 | 121.21 (13) |
C2—C3—H3 | 120.3 | C12—C11—S | 119.25 (10) |
C3—C4—C5 | 119.09 (13) | C16—C11—S | 119.29 (11) |
C3—C4—C9 | 120.40 (13) | C11—C12—C13 | 119.50 (13) |
C5—C4—C9 | 120.50 (13) | C11—C12—H12 | 120.2 |
C6—C5—C4 | 122.76 (13) | C13—C12—H12 | 120.2 |
C6—C5—H5 | 118.6 | C14—C13—C12 | 118.22 (13) |
C4—C5—H5 | 118.6 | C14—C13—H13 | 120.9 |
C7—C6—C5 | 116.24 (13) | C12—C13—H13 | 120.9 |
C7—C6—H6 | 121.9 | F1—C14—C13 | 118.51 (14) |
C5—C6—H6 | 121.9 | F1—C14—C15 | 118.21 (14) |
C6—C7—O1 | 126.34 (12) | C13—C14—C15 | 123.27 (14) |
C6—C7—C2 | 123.18 (13) | C14—C15—C16 | 118.09 (14) |
O1—C7—C2 | 110.48 (12) | C14—C15—H15 | 121.0 |
C1—C8—O1 | 110.74 (12) | C16—C15—H15 | 121.0 |
C1—C8—C10 | 132.86 (14) | C15—C16—C11 | 119.64 (14) |
O1—C8—C10 | 116.40 (12) | C15—C16—H16 | 120.2 |
C4—C9—H9A | 109.5 | C11—C16—H16 | 120.2 |
O2—S—C1—C8 | 131.07 (12) | C1—C2—C7—O1 | 0.42 (14) |
C11—S—C1—C8 | −118.80 (12) | C2—C1—C8—O1 | −0.67 (16) |
O2—S—C1—C2 | −42.67 (14) | S—C1—C8—O1 | −175.53 (9) |
C11—S—C1—C2 | 67.46 (13) | C2—C1—C8—C10 | −179.96 (15) |
C8—C1—C2—C3 | −178.80 (15) | S—C1—C8—C10 | 5.2 (2) |
S—C1—C2—C3 | −4.3 (2) | C7—O1—C8—C1 | 0.92 (15) |
C8—C1—C2—C7 | 0.15 (15) | C7—O1—C8—C10 | −179.66 (12) |
S—C1—C2—C7 | 174.69 (10) | O2—S—C11—C12 | −7.30 (12) |
C7—C2—C3—C4 | −0.5 (2) | C1—S—C11—C12 | −118.67 (11) |
C1—C2—C3—C4 | 178.31 (14) | O2—S—C11—C16 | 178.43 (11) |
C2—C3—C4—C5 | 0.6 (2) | C1—S—C11—C16 | 67.07 (12) |
C2—C3—C4—C9 | −178.81 (13) | C16—C11—C12—C13 | −2.0 (2) |
C3—C4—C5—C6 | −0.1 (2) | S—C11—C12—C13 | −176.18 (10) |
C9—C4—C5—C6 | 179.28 (14) | C11—C12—C13—C14 | −0.3 (2) |
C4—C5—C6—C7 | −0.4 (2) | C12—C13—C14—F1 | −179.40 (12) |
C5—C6—C7—O1 | −179.06 (13) | C12—C13—C14—C15 | 1.6 (2) |
C5—C6—C7—C2 | 0.5 (2) | F1—C14—C15—C16 | −179.50 (13) |
C8—O1—C7—C6 | 178.76 (14) | C13—C14—C15—C16 | −0.5 (2) |
C8—O1—C7—C2 | −0.82 (15) | C14—C15—C16—C11 | −1.9 (2) |
C3—C2—C7—C6 | 0.0 (2) | C12—C11—C16—C15 | 3.1 (2) |
C1—C2—C7—C6 | −179.18 (13) | S—C11—C16—C15 | 177.30 (11) |
C3—C2—C7—O1 | 179.58 (11) |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10B···O2i | 0.98 | 2.62 | 3.554 (2) | 159 |
Symmetry code: (i) −x+2, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C16H13FO2S |
Mr | 288.32 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 11.3951 (5), 6.1223 (3), 19.6899 (9) |
β (°) | 100.155 (2) |
V (Å3) | 1352.13 (11) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.25 |
Crystal size (mm) | 0.30 × 0.30 × 0.21 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.645, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 22996, 3115, 2830 |
Rint | 0.032 |
(sin θ/λ)max (Å−1) | 0.651 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.099, 1.07 |
No. of reflections | 3115 |
No. of parameters | 183 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.30, −0.32 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10B···O2i | 0.98 | 2.62 | 3.554 (2) | 159.4 |
Symmetry code: (i) −x+2, y+1/2, −z+3/2. |
References
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Molecules containing benzofuran skeleton show various pharmacological activities such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009), antimicrobial (Khan et al., 2005) properties, and these compounds are widely occurring in nature (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing studies of the effect of side chain substituents on the solid state structures of 2-methyl-3-phenylsulfinyl-1-benzofuran analogues (Choi et al., 2007, 2008a,b), we report the crystal structure of the title compound (Fig. 1).
The benzofuran unit is essentially planar, with a mean deviation of 0.009 (1) ° from the least-squares plane defined by the nine constituent atoms. The 4-fluorophenyl ring is almost perpendicular to the plane of the benzofuran fragment [87.41 (3)°] and is tilted slightly towards it. The crystal packing (Fig. 2) is stabilized by a weak intermolecular C—H···O hydrogen bond between the methyl H atom and the oxygen of the S═O unit, with a C10—H10B···O2i (Table 1).