organic compounds
3-(4-Bromophenylsulfinyl)-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, C16H13BrO2S, the 4-bromophenyl ring makes a dihedral angle of 87.87 (6)° with the mean plane of the benzofuran fragment. In the crystal, molecules are linked by a weak π–π interaction between the 4-bromophenyl rings [centroid-to-centroid distance = 3.907 (3) Å, interplanar distance = 3.528 (3) Å and slippage = 1.679 (3) Å].
Related literature
For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Khan et al. (2005). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003). For the crystal structures of related compounds, see: Choi et al. (2010a,b).
Experimental
Crystal data
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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/S1600536812002656/kp2381sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812002656/kp2381Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812002656/kp2381Isup3.cml
3-Chloroperoxybenzoic acid 77% (269 mg, 1.2 mmol) was added in small portions to a stirred solution of 3-(4-bromophenylsulfanyl)-2,5-dimethyl-1-benzofuran (366 mg, 1.1 mmol) in dichloromethane (40 ml) at 273 K. After being stirred at room temperature for 5 h, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by
(hexane–ethyl acetate, 2:1 v/v) to afford the title compound as a colourless solid [yield 72%, m.p. 434–435 K; Rf = 0.49 (hexane–ethyl acetate, 2:1 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).C16H13BrO2S | Z = 2 |
Mr = 349.23 | F(000) = 352 |
Triclinic, P1 | Dx = 1.619 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.4145 (3) Å | Cell parameters from 7068 reflections |
b = 10.0266 (5) Å | θ = 2.5–28.2° |
c = 11.7639 (6) Å | µ = 3.01 mm−1 |
α = 101.606 (3)° | T = 173 K |
β = 92.240 (2)° | Block, colourless |
γ = 103.932 (2)° | 0.30 × 0.23 × 0.20 mm |
V = 716.28 (6) Å3 |
Bruker SMART APEXII CCD diffractometer | 3507 independent reflections |
Radiation source: rotating anode | 3048 reflections with I > 2σ(I) |
Graphite multilayer monochromator | Rint = 0.044 |
Detector resolution: 10.0 pixels mm-1 | θmax = 28.3°, θmin = 1.8° |
ϕ and ω scans | h = −8→8 |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | k = −13→13 |
Tmin = 0.518, Tmax = 0.746 | l = −15→15 |
12848 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)] = 0.033 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.087 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0431P)2 + 0.3244P] where P = (Fo2 + 2Fc2)/3 |
3507 reflections | (Δ/σ)max = 0.001 |
183 parameters | Δρmax = 0.57 e Å−3 |
0 restraints | Δρmin = −0.59 e Å−3 |
C16H13BrO2S | γ = 103.932 (2)° |
Mr = 349.23 | V = 716.28 (6) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.4145 (3) Å | Mo Kα radiation |
b = 10.0266 (5) Å | µ = 3.01 mm−1 |
c = 11.7639 (6) Å | T = 173 K |
α = 101.606 (3)° | 0.30 × 0.23 × 0.20 mm |
β = 92.240 (2)° |
Bruker SMART APEXII CCD diffractometer | 3507 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 3048 reflections with I > 2σ(I) |
Tmin = 0.518, Tmax = 0.746 | Rint = 0.044 |
12848 measured reflections |
R[F2 > 2σ(F2)] = 0.033 | 0 restraints |
wR(F2) = 0.087 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.57 e Å−3 |
3507 reflections | Δρmin = −0.59 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 | ||
Br1 | 1.23629 (4) | 0.91785 (2) | 0.915580 (19) | 0.04170 (10) | |
S1 | 0.69071 (9) | 0.27380 (6) | 0.84528 (4) | 0.03194 (13) | |
O1 | 0.8013 (2) | 0.10195 (16) | 0.53135 (13) | 0.0336 (3) | |
O2 | 0.4646 (3) | 0.2757 (2) | 0.86938 (15) | 0.0462 (4) | |
C1 | 0.6970 (3) | 0.2139 (2) | 0.69530 (17) | 0.0274 (4) | |
C2 | 0.5786 (3) | 0.2405 (2) | 0.59942 (17) | 0.0265 (4) | |
C3 | 0.4234 (4) | 0.3139 (2) | 0.5861 (2) | 0.0332 (5) | |
H3 | 0.3725 | 0.3633 | 0.6524 | 0.040* | |
C4 | 0.3442 (4) | 0.3134 (3) | 0.4742 (2) | 0.0396 (5) | |
C5 | 0.4239 (4) | 0.2411 (3) | 0.3781 (2) | 0.0453 (6) | |
H5 | 0.3709 | 0.2433 | 0.3022 | 0.054* | |
C6 | 0.5762 (4) | 0.1665 (3) | 0.3889 (2) | 0.0410 (5) | |
H6 | 0.6276 | 0.1169 | 0.3229 | 0.049* | |
C7 | 0.6492 (3) | 0.1686 (2) | 0.50126 (18) | 0.0303 (4) | |
C8 | 0.8253 (3) | 0.1306 (2) | 0.65040 (18) | 0.0298 (4) | |
C9 | 0.1740 (4) | 0.3903 (3) | 0.4573 (3) | 0.0570 (8) | |
H9A | 0.0339 | 0.3220 | 0.4338 | 0.086* | |
H9B | 0.2114 | 0.4437 | 0.3966 | 0.086* | |
H9C | 0.1660 | 0.4550 | 0.5305 | 0.086* | |
C10 | 0.9846 (4) | 0.0710 (3) | 0.7040 (2) | 0.0406 (5) | |
H10A | 1.1308 | 0.1223 | 0.6938 | 0.061* | |
H10B | 0.9612 | −0.0286 | 0.6664 | 0.061* | |
H10C | 0.9671 | 0.0797 | 0.7874 | 0.061* | |
C11 | 0.8359 (3) | 0.4538 (2) | 0.85581 (16) | 0.0277 (4) | |
C12 | 0.7417 (4) | 0.5610 (2) | 0.89976 (19) | 0.0334 (5) | |
H12 | 0.5963 | 0.5394 | 0.9183 | 0.040* | |
C13 | 0.8589 (4) | 0.7004 (2) | 0.91705 (19) | 0.0354 (5) | |
H13 | 0.7951 | 0.7747 | 0.9475 | 0.042* | |
C14 | 1.0693 (4) | 0.7290 (2) | 0.88928 (17) | 0.0304 (4) | |
C15 | 1.1664 (4) | 0.6220 (2) | 0.84572 (19) | 0.0344 (5) | |
H15 | 1.3117 | 0.6438 | 0.8269 | 0.041* | |
C16 | 1.0498 (4) | 0.4837 (2) | 0.83008 (19) | 0.0342 (5) | |
H16 | 1.1152 | 0.4094 | 0.8019 | 0.041* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.05053 (18) | 0.03378 (14) | 0.03637 (14) | 0.00588 (11) | 0.00285 (10) | 0.00355 (9) |
S1 | 0.0324 (3) | 0.0376 (3) | 0.0233 (2) | 0.0047 (2) | 0.0038 (2) | 0.0056 (2) |
O1 | 0.0309 (8) | 0.0348 (8) | 0.0329 (8) | 0.0088 (7) | 0.0073 (6) | 0.0011 (6) |
O2 | 0.0323 (9) | 0.0570 (11) | 0.0400 (9) | −0.0004 (8) | 0.0154 (7) | 0.0009 (8) |
C1 | 0.0257 (10) | 0.0285 (10) | 0.0262 (9) | 0.0053 (8) | 0.0017 (8) | 0.0039 (8) |
C2 | 0.0227 (10) | 0.0271 (10) | 0.0267 (9) | 0.0010 (8) | 0.0024 (7) | 0.0051 (8) |
C3 | 0.0261 (11) | 0.0345 (11) | 0.0393 (12) | 0.0057 (9) | 0.0036 (9) | 0.0107 (9) |
C4 | 0.0250 (11) | 0.0403 (12) | 0.0530 (14) | −0.0023 (9) | −0.0041 (10) | 0.0235 (11) |
C5 | 0.0367 (13) | 0.0582 (16) | 0.0352 (12) | −0.0070 (11) | −0.0066 (10) | 0.0214 (11) |
C6 | 0.0392 (13) | 0.0504 (14) | 0.0256 (10) | −0.0011 (11) | 0.0024 (9) | 0.0056 (9) |
C7 | 0.0263 (11) | 0.0316 (10) | 0.0284 (10) | 0.0005 (8) | 0.0028 (8) | 0.0042 (8) |
C8 | 0.0266 (11) | 0.0262 (10) | 0.0334 (10) | 0.0036 (8) | 0.0022 (8) | 0.0032 (8) |
C9 | 0.0308 (14) | 0.0602 (17) | 0.086 (2) | 0.0058 (12) | −0.0083 (13) | 0.0402 (16) |
C10 | 0.0327 (13) | 0.0368 (12) | 0.0536 (14) | 0.0123 (10) | 0.0005 (11) | 0.0092 (10) |
C11 | 0.0273 (10) | 0.0342 (10) | 0.0201 (9) | 0.0073 (8) | 0.0007 (7) | 0.0029 (7) |
C12 | 0.0263 (11) | 0.0439 (12) | 0.0320 (11) | 0.0135 (9) | 0.0066 (8) | 0.0065 (9) |
C13 | 0.0388 (13) | 0.0388 (12) | 0.0316 (10) | 0.0182 (10) | 0.0056 (9) | 0.0038 (9) |
C14 | 0.0350 (12) | 0.0308 (10) | 0.0224 (9) | 0.0061 (9) | −0.0023 (8) | 0.0026 (8) |
C15 | 0.0263 (11) | 0.0395 (12) | 0.0358 (11) | 0.0090 (9) | 0.0052 (9) | 0.0035 (9) |
C16 | 0.0303 (11) | 0.0372 (12) | 0.0344 (11) | 0.0117 (9) | 0.0079 (9) | 0.0011 (9) |
Br1—C14 | 1.895 (2) | C8—C10 | 1.482 (3) |
S1—O2 | 1.4927 (18) | C9—H9A | 0.9800 |
S1—C1 | 1.751 (2) | C9—H9B | 0.9800 |
S1—C11 | 1.798 (2) | C9—H9C | 0.9800 |
O1—C8 | 1.367 (3) | C10—H10A | 0.9800 |
O1—C7 | 1.381 (3) | C10—H10B | 0.9800 |
C1—C8 | 1.357 (3) | C10—H10C | 0.9800 |
C1—C2 | 1.439 (3) | C11—C12 | 1.379 (3) |
C2—C7 | 1.386 (3) | C11—C16 | 1.391 (3) |
C2—C3 | 1.395 (3) | C12—C13 | 1.388 (3) |
C3—C4 | 1.391 (3) | C12—H12 | 0.9500 |
C3—H3 | 0.9500 | C13—C14 | 1.377 (3) |
C4—C5 | 1.399 (4) | C13—H13 | 0.9500 |
C4—C9 | 1.508 (3) | C14—C15 | 1.389 (3) |
C5—C6 | 1.382 (4) | C15—C16 | 1.379 (3) |
C5—H5 | 0.9500 | C15—H15 | 0.9500 |
C6—C7 | 1.380 (3) | C16—H16 | 0.9500 |
C6—H6 | 0.9500 | ||
O2—S1—C1 | 108.74 (10) | C4—C9—H9B | 109.5 |
O2—S1—C11 | 106.52 (10) | H9A—C9—H9B | 109.5 |
C1—S1—C11 | 97.81 (10) | C4—C9—H9C | 109.5 |
C8—O1—C7 | 106.09 (16) | H9A—C9—H9C | 109.5 |
C8—C1—C2 | 107.82 (18) | H9B—C9—H9C | 109.5 |
C8—C1—S1 | 122.92 (16) | C8—C10—H10A | 109.5 |
C2—C1—S1 | 129.26 (16) | C8—C10—H10B | 109.5 |
C7—C2—C3 | 119.4 (2) | H10A—C10—H10B | 109.5 |
C7—C2—C1 | 104.22 (18) | C8—C10—H10C | 109.5 |
C3—C2—C1 | 136.4 (2) | H10A—C10—H10C | 109.5 |
C4—C3—C2 | 118.9 (2) | H10B—C10—H10C | 109.5 |
C4—C3—H3 | 120.6 | C12—C11—C16 | 120.6 (2) |
C2—C3—H3 | 120.6 | C12—C11—S1 | 119.81 (17) |
C3—C4—C5 | 119.4 (2) | C16—C11—S1 | 119.33 (16) |
C3—C4—C9 | 120.0 (3) | C11—C12—C13 | 120.2 (2) |
C5—C4—C9 | 120.6 (2) | C11—C12—H12 | 119.9 |
C6—C5—C4 | 122.9 (2) | C13—C12—H12 | 119.9 |
C6—C5—H5 | 118.5 | C14—C13—C12 | 118.8 (2) |
C4—C5—H5 | 118.5 | C14—C13—H13 | 120.6 |
C7—C6—C5 | 115.9 (2) | C12—C13—H13 | 120.6 |
C7—C6—H6 | 122.0 | C13—C14—C15 | 121.5 (2) |
C5—C6—H6 | 122.0 | C13—C14—Br1 | 119.97 (16) |
C6—C7—O1 | 125.3 (2) | C15—C14—Br1 | 118.46 (17) |
C6—C7—C2 | 123.5 (2) | C16—C15—C14 | 119.3 (2) |
O1—C7—C2 | 111.16 (18) | C16—C15—H15 | 120.3 |
C1—C8—O1 | 110.71 (18) | C14—C15—H15 | 120.3 |
C1—C8—C10 | 133.1 (2) | C15—C16—C11 | 119.6 (2) |
O1—C8—C10 | 116.15 (19) | C15—C16—H16 | 120.2 |
C4—C9—H9A | 109.5 | C11—C16—H16 | 120.2 |
O2—S1—C1—C8 | −143.25 (19) | C1—C2—C7—O1 | −0.3 (2) |
C11—S1—C1—C8 | 106.29 (19) | C2—C1—C8—O1 | 0.8 (2) |
O2—S1—C1—C2 | 37.3 (2) | S1—C1—C8—O1 | −178.83 (14) |
C11—S1—C1—C2 | −73.2 (2) | C2—C1—C8—C10 | 178.7 (2) |
C8—C1—C2—C7 | −0.3 (2) | S1—C1—C8—C10 | −0.9 (4) |
S1—C1—C2—C7 | 179.30 (17) | C7—O1—C8—C1 | −1.0 (2) |
C8—C1—C2—C3 | 178.9 (2) | C7—O1—C8—C10 | −179.27 (19) |
S1—C1—C2—C3 | −1.5 (4) | O2—S1—C11—C12 | 10.2 (2) |
C7—C2—C3—C4 | −0.3 (3) | C1—S1—C11—C12 | 122.51 (17) |
C1—C2—C3—C4 | −179.4 (2) | O2—S1—C11—C16 | −175.97 (17) |
C2—C3—C4—C5 | −0.8 (3) | C1—S1—C11—C16 | −63.70 (18) |
C2—C3—C4—C9 | 179.1 (2) | C16—C11—C12—C13 | 1.1 (3) |
C3—C4—C5—C6 | 1.4 (4) | S1—C11—C12—C13 | 174.76 (16) |
C9—C4—C5—C6 | −178.5 (2) | C11—C12—C13—C14 | 0.2 (3) |
C4—C5—C6—C7 | −0.8 (4) | C12—C13—C14—C15 | −0.6 (3) |
C5—C6—C7—O1 | −179.6 (2) | C12—C13—C14—Br1 | −178.34 (16) |
C5—C6—C7—C2 | −0.4 (4) | C13—C14—C15—C16 | −0.1 (3) |
C8—O1—C7—C6 | −179.9 (2) | Br1—C14—C15—C16 | 177.61 (17) |
C8—O1—C7—C2 | 0.8 (2) | C14—C15—C16—C11 | 1.3 (3) |
C3—C2—C7—C6 | 0.9 (3) | C12—C11—C16—C15 | −1.8 (3) |
C1—C2—C7—C6 | −179.7 (2) | S1—C11—C16—C15 | −175.56 (17) |
C3—C2—C7—O1 | −179.69 (18) |
Experimental details
Crystal data | |
Chemical formula | C16H13BrO2S |
Mr | 349.23 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 6.4145 (3), 10.0266 (5), 11.7639 (6) |
α, β, γ (°) | 101.606 (3), 92.240 (2), 103.932 (2) |
V (Å3) | 716.28 (6) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 3.01 |
Crystal size (mm) | 0.30 × 0.23 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.518, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12848, 3507, 3048 |
Rint | 0.044 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.087, 1.04 |
No. of reflections | 3507 |
No. of parameters | 183 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.57, −0.59 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).
Acknowledgements
This work was supported by the Blue-Bio Industry Regional Innovation Centre (grant No. RIC08-06-07) at Dongeui University as an RIC programme under the Ministry of Knowledge Economy and Busan city.
References
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Many compounds involving a benzofuran ring have drawn much attention owing to their valuable biological properties such as antibacterial, antifungal, antitumor, and antiviral activities (Aslam et al., 2009; Galal et al., 2009; Khan et al., 2005). These benzofuran derivatives occur in a wide range of natural products (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our continuing study of 2,5-dimethyl-1-benzofuran derivatives containing either 3-(4-fluorophenylsulfinyl) (Choi et al., 2010a) or 3-(4-chlorophenylsufinyl) (Choi et al., 2010b) substituents, we report herein the crystal structure of the title compound.
In the title molecule (Fig. 1), the benzofuran unit is planar with the mean deviation of 0.006 (2) Å from the least-squares plane defined by the nine constituent atoms. The dihedral angle between the 4-bromophenyl ring and the mean plane of the benzofuran fragment is 87.87 (6)°. The crystal packing (Fig. 2) is further stabilised by a weak π–π interaction between the 4-bromophenyl rings of adjacent molecules, with a Cg···Cgi distance of 3.907 (3) Å and an interplanar distance of 3.528 (3) Å resulting in a slippage of 1.679 (3) Å (Cg is the centroid of the C11–C16 4-bromophenyl ring).