organic compounds
of 5-chloro-2-(3-fluorophenyl)-3-methylsulfinyl-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, C15H10ClFO2S, the dihedral angle between the plane of the benzofuran ring system [r.m.s. deviation = 0.013 (1) Å] and that of the 3-fluorophenyl ring [r.m.s. deviation = 0.005 (1) Å] is 31.36 (5)°. In the crystal, molecules are linked by two different pairs of C—H⋯O hydrogen bonds, forming inversion dimers.
Keywords: crystal structure; benzofuran; 3-fluorophenyl; C—H⋯O hydrogen bonds.
CCDC reference: 1017893
1. Related literature
For the pharmaceutical properties of compounds containing the benzofuran moiety, see: Aslam et al. (2009); Choi et al. (2003); Galal et al. (2009); Khan et al. (2005); Ono et al. (2002). For natural products with a benzofuran ring, see: Akgul & Anil (2003); Soekamto et al. (2003). For the synthesis of the starting material 5-chloro-2-(3-fluorophenyl)-3-methylsulfanyl-1-benzofuran, see: Choi et al. (1999). For a related structure, see: Choi et al. (2009).
2. Experimental
2.1. Crystal data
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2.3. 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 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97.
Supporting information
CCDC reference: 1017893
10.1107/S1600536814017966/zq2226sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814017966/zq2226Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536814017966/zq2226Isup3.cml
The starting material 5-chloro-2-(3-fluorophenyl)-3-methylsulfanyl-1-benzofuran was prepared by literature method (Choi et al. 1999). 3-Chloroperoxybenzoic acid (77%, 269 mg, 1.2 mmol) was added in small portions to a stirred solution of the starting material (322 mg, 1.1 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 6h, the mixture was washed with saturated sodium bicarbonate solution (2 X 20 mL) and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by
(hexane–ethyl acetate, 1:1 v/v) to afford the title compound as a colorless solid [yield 73% (248 mg); m.p. 483–484 K; Rf = 0.48 (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 (120 mg) in acetone (20 mL) 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.The positions of methyl hydrogens were optimized using the SHELXL-97's command AFIX 137 (Sheldrick, 2008).
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 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C15H10ClFO2S | Z = 2 |
Mr = 308.74 | F(000) = 316 |
Triclinic, P1 | Dx = 1.568 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 8.0038 (1) Å | Cell parameters from 6836 reflections |
b = 8.4322 (1) Å | θ = 2.6–28.5° |
c = 10.6782 (2) Å | µ = 0.46 mm−1 |
α = 88.933 (1)° | T = 173 K |
β = 81.008 (1)° | Block, colourless |
γ = 66.859 (1)° | 0.47 × 0.34 × 0.33 mm |
V = 653.81 (2) Å3 |
Bruker SMART APEXII CCD diffractometer | 3124 independent reflections |
Radiation source: rotating anode | 2887 reflections with I > 2σ(I) |
Graphite multilayer monochromator | Rint = 0.022 |
Detector resolution: 10.0 pixels mm-1 | θmax = 28.0°, θmin = 1.9° |
ϕ and ω scans | h = −10→10 |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | k = −11→11 |
Tmin = 0.813, Tmax = 0.863 | l = −14→13 |
11737 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)] = 0.032 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.086 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0458P)2 + 0.2424P] where P = (Fo2 + 2Fc2)/3 |
3124 reflections | (Δ/σ)max < 0.001 |
182 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.44 e Å−3 |
C15H10ClFO2S | γ = 66.859 (1)° |
Mr = 308.74 | V = 653.81 (2) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.0038 (1) Å | Mo Kα radiation |
b = 8.4322 (1) Å | µ = 0.46 mm−1 |
c = 10.6782 (2) Å | T = 173 K |
α = 88.933 (1)° | 0.47 × 0.34 × 0.33 mm |
β = 81.008 (1)° |
Bruker SMART APEXII CCD diffractometer | 3124 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2887 reflections with I > 2σ(I) |
Tmin = 0.813, Tmax = 0.863 | Rint = 0.022 |
11737 measured reflections |
R[F2 > 2σ(F2)] = 0.032 | 0 restraints |
wR(F2) = 0.086 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.30 e Å−3 |
3124 reflections | Δρmin = −0.44 e Å−3 |
182 parameters |
Experimental. 1H NMR (δ p.p.m., CDCl3, 400 Hz): 8.23 (d, J = 2.04 Hz, 1H), 7.62 (d, J = 7.88 Hz, 1H), 7.54-7.58 (m, 1H), 7.45-7.52 (m, 2H), 7.38 (dd, J = 8.88 and 2.04 Hz, 1H), 7.16-7.22 (m, 1H), 3.11 (s, 3H). |
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 | ||
Cl1 | 0.82187 (5) | −0.13963 (5) | −0.02027 (3) | 0.03515 (11) | |
S1 | 0.21038 (4) | 0.30346 (4) | 0.39543 (3) | 0.02300 (10) | |
F1 | 0.53226 (14) | 0.29209 (13) | 0.95736 (8) | 0.0395 (2) | |
O1 | 0.70635 (13) | 0.13881 (12) | 0.49383 (9) | 0.0234 (2) | |
O2 | 0.17787 (15) | 0.16956 (13) | 0.32625 (11) | 0.0325 (2) | |
C1 | 0.44633 (17) | 0.21871 (16) | 0.40865 (12) | 0.0210 (3) | |
C2 | 0.59652 (17) | 0.10631 (16) | 0.31628 (12) | 0.0210 (3) | |
C3 | 0.61509 (18) | 0.04393 (17) | 0.19238 (13) | 0.0231 (3) | |
H3 | 0.5120 | 0.0719 | 0.1499 | 0.028* | |
C4 | 0.79058 (19) | −0.06027 (18) | 0.13484 (13) | 0.0252 (3) | |
C5 | 0.94567 (19) | −0.10505 (18) | 0.19490 (14) | 0.0275 (3) | |
H5 | 1.0635 | −0.1775 | 0.1510 | 0.033* | |
C6 | 0.92781 (19) | −0.04413 (18) | 0.31773 (14) | 0.0265 (3) | |
H6 | 1.0308 | −0.0728 | 0.3605 | 0.032* | |
C7 | 0.75209 (18) | 0.06058 (16) | 0.37470 (13) | 0.0221 (3) | |
C8 | 0.51944 (17) | 0.23358 (16) | 0.51261 (13) | 0.0214 (3) | |
C9 | 0.44315 (18) | 0.32961 (17) | 0.63441 (12) | 0.0216 (3) | |
C10 | 0.29269 (19) | 0.48798 (18) | 0.64645 (13) | 0.0256 (3) | |
H10 | 0.2383 | 0.5349 | 0.5740 | 0.031* | |
C11 | 0.2218 (2) | 0.57761 (18) | 0.76298 (14) | 0.0281 (3) | |
H11 | 0.1182 | 0.6846 | 0.7703 | 0.034* | |
C12 | 0.3016 (2) | 0.51149 (19) | 0.86908 (14) | 0.0296 (3) | |
H12 | 0.2542 | 0.5717 | 0.9495 | 0.036* | |
C13 | 0.4517 (2) | 0.35607 (19) | 0.85427 (13) | 0.0270 (3) | |
C14 | 0.52576 (18) | 0.26207 (17) | 0.74107 (13) | 0.0235 (3) | |
H14 | 0.6293 | 0.1551 | 0.7350 | 0.028* | |
C15 | 0.2148 (2) | 0.4624 (2) | 0.28245 (17) | 0.0365 (4) | |
H15A | 0.3053 | 0.4062 | 0.2070 | 0.055* | |
H15B | 0.2488 | 0.5481 | 0.3205 | 0.055* | |
H15C | 0.0927 | 0.5199 | 0.2581 | 0.055* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0340 (2) | 0.0413 (2) | 0.02564 (19) | −0.01237 (16) | 0.00258 (14) | −0.00911 (14) |
S1 | 0.01657 (16) | 0.02380 (17) | 0.02762 (18) | −0.00635 (12) | −0.00525 (12) | 0.00218 (12) |
F1 | 0.0448 (6) | 0.0467 (5) | 0.0251 (4) | −0.0123 (4) | −0.0156 (4) | 0.0027 (4) |
O1 | 0.0190 (4) | 0.0254 (5) | 0.0236 (5) | −0.0056 (4) | −0.0057 (4) | −0.0006 (4) |
O2 | 0.0296 (5) | 0.0282 (5) | 0.0451 (6) | −0.0133 (4) | −0.0166 (5) | 0.0030 (4) |
C1 | 0.0169 (6) | 0.0214 (6) | 0.0233 (6) | −0.0058 (5) | −0.0038 (5) | 0.0009 (5) |
C2 | 0.0181 (6) | 0.0204 (6) | 0.0238 (6) | −0.0069 (5) | −0.0034 (5) | 0.0025 (5) |
C3 | 0.0220 (6) | 0.0244 (6) | 0.0232 (6) | −0.0091 (5) | −0.0048 (5) | 0.0016 (5) |
C4 | 0.0268 (7) | 0.0245 (6) | 0.0236 (6) | −0.0104 (5) | −0.0008 (5) | −0.0017 (5) |
C5 | 0.0206 (6) | 0.0255 (6) | 0.0316 (7) | −0.0058 (5) | 0.0007 (5) | −0.0016 (5) |
C6 | 0.0189 (6) | 0.0257 (6) | 0.0326 (7) | −0.0058 (5) | −0.0057 (5) | 0.0008 (5) |
C7 | 0.0213 (6) | 0.0213 (6) | 0.0233 (6) | −0.0077 (5) | −0.0045 (5) | 0.0009 (5) |
C8 | 0.0178 (6) | 0.0201 (6) | 0.0248 (6) | −0.0058 (5) | −0.0039 (5) | 0.0021 (5) |
C9 | 0.0205 (6) | 0.0231 (6) | 0.0226 (6) | −0.0099 (5) | −0.0044 (5) | 0.0005 (5) |
C10 | 0.0248 (7) | 0.0250 (6) | 0.0265 (7) | −0.0082 (5) | −0.0067 (5) | 0.0018 (5) |
C11 | 0.0252 (7) | 0.0249 (6) | 0.0306 (7) | −0.0065 (5) | −0.0026 (5) | −0.0036 (5) |
C12 | 0.0303 (7) | 0.0326 (7) | 0.0259 (7) | −0.0132 (6) | −0.0019 (6) | −0.0052 (5) |
C13 | 0.0296 (7) | 0.0330 (7) | 0.0231 (7) | −0.0155 (6) | −0.0095 (5) | 0.0040 (5) |
C14 | 0.0214 (6) | 0.0246 (6) | 0.0258 (7) | −0.0096 (5) | −0.0055 (5) | 0.0017 (5) |
C15 | 0.0326 (8) | 0.0312 (7) | 0.0499 (10) | −0.0138 (6) | −0.0176 (7) | 0.0173 (7) |
Cl1—C4 | 1.7418 (14) | C6—C7 | 1.3800 (19) |
S1—O2 | 1.4866 (11) | C6—H6 | 0.9500 |
S1—C1 | 1.7652 (13) | C8—C9 | 1.4568 (18) |
S1—C15 | 1.7937 (15) | C9—C10 | 1.3943 (18) |
F1—C13 | 1.3584 (16) | C9—C14 | 1.4049 (18) |
O1—C7 | 1.3724 (16) | C10—C11 | 1.385 (2) |
O1—C8 | 1.3745 (15) | C10—H10 | 0.9500 |
C1—C8 | 1.3625 (18) | C11—C12 | 1.388 (2) |
C1—C2 | 1.4439 (17) | C11—H11 | 0.9500 |
C2—C7 | 1.3945 (18) | C12—C13 | 1.377 (2) |
C2—C3 | 1.3972 (18) | C12—H12 | 0.9500 |
C3—C4 | 1.3794 (19) | C13—C14 | 1.372 (2) |
C3—H3 | 0.9500 | C14—H14 | 0.9500 |
C4—C5 | 1.402 (2) | C15—H15A | 0.9800 |
C5—C6 | 1.383 (2) | C15—H15B | 0.9800 |
C5—H5 | 0.9500 | C15—H15C | 0.9800 |
O2—S1—C1 | 107.08 (6) | C1—C8—C9 | 133.92 (12) |
O2—S1—C15 | 105.95 (7) | O1—C8—C9 | 115.20 (11) |
C1—S1—C15 | 97.48 (7) | C10—C9—C14 | 119.61 (12) |
C7—O1—C8 | 106.62 (10) | C10—C9—C8 | 121.37 (12) |
C8—C1—C2 | 106.92 (11) | C14—C9—C8 | 119.01 (12) |
C8—C1—S1 | 126.40 (10) | C11—C10—C9 | 120.64 (13) |
C2—C1—S1 | 126.42 (10) | C11—C10—H10 | 119.7 |
C7—C2—C3 | 119.41 (12) | C9—C10—H10 | 119.7 |
C7—C2—C1 | 105.03 (11) | C10—C11—C12 | 120.19 (13) |
C3—C2—C1 | 135.54 (12) | C10—C11—H11 | 119.9 |
C4—C3—C2 | 116.67 (12) | C12—C11—H11 | 119.9 |
C4—C3—H3 | 121.7 | C13—C12—C11 | 118.02 (13) |
C2—C3—H3 | 121.7 | C13—C12—H12 | 121.0 |
C3—C4—C5 | 123.22 (13) | C11—C12—H12 | 121.0 |
C3—C4—Cl1 | 118.56 (11) | F1—C13—C14 | 117.86 (13) |
C5—C4—Cl1 | 118.22 (11) | F1—C13—C12 | 118.28 (13) |
C6—C5—C4 | 120.30 (13) | C14—C13—C12 | 123.86 (13) |
C6—C5—H5 | 119.8 | C13—C14—C9 | 117.67 (12) |
C4—C5—H5 | 119.8 | C13—C14—H14 | 121.2 |
C7—C6—C5 | 116.25 (12) | C9—C14—H14 | 121.2 |
C7—C6—H6 | 121.9 | S1—C15—H15A | 109.5 |
C5—C6—H6 | 121.9 | S1—C15—H15B | 109.5 |
O1—C7—C6 | 125.27 (12) | H15A—C15—H15B | 109.5 |
O1—C7—C2 | 110.56 (11) | S1—C15—H15C | 109.5 |
C6—C7—C2 | 124.14 (13) | H15A—C15—H15C | 109.5 |
C1—C8—O1 | 110.86 (11) | H15B—C15—H15C | 109.5 |
O2—S1—C1—C8 | −138.71 (12) | C1—C2—C7—C6 | −178.69 (13) |
C15—S1—C1—C8 | 112.01 (13) | C2—C1—C8—O1 | 0.06 (15) |
O2—S1—C1—C2 | 34.63 (13) | S1—C1—C8—O1 | 174.46 (9) |
C15—S1—C1—C2 | −74.66 (13) | C2—C1—C8—C9 | 178.33 (14) |
C8—C1—C2—C7 | 0.43 (14) | S1—C1—C8—C9 | −7.3 (2) |
S1—C1—C2—C7 | −173.96 (10) | C7—O1—C8—C1 | −0.54 (14) |
C8—C1—C2—C3 | −178.15 (15) | C7—O1—C8—C9 | −179.16 (11) |
S1—C1—C2—C3 | 7.5 (2) | C1—C8—C9—C10 | −30.9 (2) |
C7—C2—C3—C4 | −0.39 (19) | O1—C8—C9—C10 | 147.27 (12) |
C1—C2—C3—C4 | 178.04 (14) | C1—C8—C9—C14 | 150.28 (15) |
C2—C3—C4—C5 | 0.4 (2) | O1—C8—C9—C14 | −31.51 (17) |
C2—C3—C4—Cl1 | −179.30 (10) | C14—C9—C10—C11 | −1.3 (2) |
C3—C4—C5—C6 | −0.2 (2) | C8—C9—C10—C11 | 179.97 (13) |
Cl1—C4—C5—C6 | 179.54 (11) | C9—C10—C11—C12 | 0.9 (2) |
C4—C5—C6—C7 | −0.1 (2) | C10—C11—C12—C13 | 0.1 (2) |
C8—O1—C7—C6 | 178.70 (13) | C11—C12—C13—F1 | 178.95 (13) |
C8—O1—C7—C2 | 0.83 (14) | C11—C12—C13—C14 | −0.6 (2) |
C5—C6—C7—O1 | −177.52 (12) | F1—C13—C14—C9 | −179.35 (12) |
C5—C6—C7—C2 | 0.1 (2) | C12—C13—C14—C9 | 0.2 (2) |
C3—C2—C7—O1 | 178.08 (11) | C10—C9—C14—C13 | 0.7 (2) |
C1—C2—C7—O1 | −0.78 (15) | C8—C9—C14—C13 | 179.52 (12) |
C3—C2—C7—C6 | 0.2 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···O2i | 0.95 | 2.57 | 3.3470 (18) | 139 |
C14—H14···O2ii | 0.95 | 2.59 | 3.4884 (17) | 157 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···O2i | 0.95 | 2.57 | 3.3470 (18) | 138.9 |
C14—H14···O2ii | 0.95 | 2.59 | 3.4884 (17) | 156.8 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y, −z+1. |
Acknowledgements
The X-ray centre of the Gyeongsang National University is acknowledged for providing access to the single-crystal diffractometer.
References
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Recently, a number of benzofuran compounds have drawn much attention owing to their interesting pharmaceutical properties such as antibacterial and antifungal, antitumor and antiviral, antimicrobial activities (Aslam et al. 2009; Galal et al., 2009; Khan et al., 2005), and potential inhibitors of β-amyloid formation (Choi et al., 2003, Ono et al., 2002). These benzofuran derivatives occur in a wide range of natural products (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing project of 2-aryl-5-chloro-3-methylsulfinyl-1-benzofuran derivatives containing 4-fluorophenyl substituent in 2-position (Choi et al., 2009), we report herein on the crystal structure of the title compound.
In the title molecule (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.013 (1) Å from the least-squares plane defined by the nine constituent atoms. The 3-fluorophenyl ring is essentially planar, with a mean deviation of 0.005 (1) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring system and the 3-fluorophenyl ring is 31.36 (5)°. In the crystal structure (Fig. 2), molecules are linked by two different pairs of C—H···O hydrogen bonds (Table 1), forming inversion dimers.