organic compounds
of 2,5-dimethyl-3-(2-methylphenylsulfinyl)-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, C17H16O2S, the dihedral angle between the benzofuran ring system [r.m.s. deviation = 0.009 (1) Å] and the 2-methylphenyl ring is 86.72 (4)°. In the crystal, weak C—H⋯O hydrogen bonds link the molecules into columns along the b-axis direction.
Keywords: crystal structure; benzofuran; 2-methylphenyl; C—H⋯O hydrogen bonds.
CCDC reference: 1410058
1. Related literature
For the pharmacological properties of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Howlett et al. (1999); Wahab Khan et al. (2005); Ono et al. (2002). For natural products with a benzofuran ring, see: Akgul & Anil (2003); Soekamto et al. (2003). For a related structure, see: Choi et al. (2012). For further synthetic details, see: Choi et al. (1999).
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: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008).
Supporting information
CCDC reference: 1410058
https://doi.org/10.1107/S2056989015012773/cv5492sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015012773/cv5492Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015012773/cv5492Isup3.cml
The starting material 2,5-dimethyl-3-(2-methylphenylsulfanyl)-1-benzofuran was prepared by literature method (Choi et al. 1999). 3-Chloroperoxybenzoic acid (77%, 224 mg, 1.0 mmol) was added in small portions to a stirred solution of 2,5-dimethyl-3-(2-methylphenylsulfanyl)-1-benzofuran (241 mg, 0.9 mmol) in dichloromethane (25 ml) at 273 K. After being stirred at room temperature for 8h, the mixture was washed with saturated sodium bicarbonate solution (2 X 10 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, 2:1 v/v) to afford the title compound as a colorless solid [yield 68% (174 mg); m.p. 415–416 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 (21 mg) in ethyl acetate (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 command AFIX in SHELXL-2014/7 (Sheldrick, 2015)
Benzofuran derivatives show interesting pharmacological properties such as antibacterial and antifungal, antitumor and antiviral, antimicrobial activities (Aslam et al. 2009; Galal et al., 2009; Wahab Khan et al., 2005), and potential inhibitor of β-amyloid aggregation (Howlett et al., 1999; Ono et al., 2002). These benzofuran compounds occur in a great number of natural products. (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our continuing project on benzofuran derivatives (Choi et al., 2012), we report herein on the of the title compound.
In the title molecule (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.009 (1) Å from the least-squares plane defined by the nine constituent atoms. The 2-methylphenyl ring is essentially planar, with a mean deviation of 0.004 (1) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring and the 2-methylphenyl ring is 86.72 (4)°. In the crystal, molecules are linked into a chain along the b axis direction by C—H···O hydrogen bonds (Table 1 and Fig. 2). These molecules are connected on either side of this chain by further C—H···O hydrogen bonds (Table 1 and Fig. 2).
For the pharmacological properties of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Howlett et al. (1999); Wahab Khan et al. (2005); Ono et al. (2002). For natural products with a benzofuran ring, see: Akgul & Anil (2003); Soekamto et al. (2003). For a related structure, see: Choi et al. (2012). For further synthetic details, see: Choi et al. (1999).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2008).C17H16O2S | F(000) = 600 |
Mr = 284.36 | Dx = 1.332 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 10.8458 (2) Å | Cell parameters from 9125 reflections |
b = 8.0139 (1) Å | θ = 2.5–28.1° |
c = 16.4295 (2) Å | µ = 0.23 mm−1 |
β = 96.709 (1)° | T = 173 K |
V = 1418.23 (4) Å3 | Block, colourless |
Z = 4 | 0.44 × 0.33 × 0.30 mm |
Bruker SMART APEXII CCD diffractometer | 3529 independent reflections |
Radiation source: rotating anode | 3091 reflections with I > 2σ(I) |
Graphite multilayer monochromator | Rint = 0.033 |
Detector resolution: 10.0 pixels mm-1 | θmax = 28.4°, θmin = 2.1° |
φ and ω scans | h = −14→14 |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | k = −10→10 |
Tmin = 0.692, Tmax = 0.746 | l = −21→20 |
25176 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)] = 0.037 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.103 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0515P)2 + 0.5244P] where P = (Fo2 + 2Fc2)/3 |
3529 reflections | (Δ/σ)max = 0.001 |
184 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
C17H16O2S | V = 1418.23 (4) Å3 |
Mr = 284.36 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 10.8458 (2) Å | µ = 0.23 mm−1 |
b = 8.0139 (1) Å | T = 173 K |
c = 16.4295 (2) Å | 0.44 × 0.33 × 0.30 mm |
β = 96.709 (1)° |
Bruker SMART APEXII CCD diffractometer | 3529 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 3091 reflections with I > 2σ(I) |
Tmin = 0.692, Tmax = 0.746 | Rint = 0.033 |
25176 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.103 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.30 e Å−3 |
3529 reflections | Δρmin = −0.27 e Å−3 |
184 parameters |
Experimental. 1H NMR (δ p.p.m., CDCl3, 400 Hz): 8.35 (d, J = 7.88 Hz, 1H), 7.53–7.57 (m, 1H), 7.38–7.42 (m, 1H), 7.26 (d, J = 7.02 Hz, 1H), 7.15 (d, J = 7.52 Hz, 1H), 6.98–7.03 (m, 2H), 2.73 (s, 3H), 2.25 (s, 3H), 2.13 (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. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.17973 (3) | 0.37549 (4) | 0.52324 (2) | 0.02675 (11) | |
O1 | 0.17654 (10) | 0.24730 (14) | 0.75315 (6) | 0.0349 (2) | |
O2 | 0.21361 (11) | 0.55407 (13) | 0.51308 (6) | 0.0381 (3) | |
C1 | 0.21664 (12) | 0.31930 (17) | 0.62666 (8) | 0.0250 (3) | |
C2 | 0.33439 (12) | 0.30795 (16) | 0.67783 (8) | 0.0236 (3) | |
C3 | 0.45906 (12) | 0.33131 (16) | 0.66789 (8) | 0.0255 (3) | |
H3 | 0.4825 | 0.3619 | 0.6160 | 0.031* | |
C4 | 0.54881 (13) | 0.30933 (18) | 0.73475 (9) | 0.0307 (3) | |
C5 | 0.51194 (15) | 0.2614 (2) | 0.81059 (9) | 0.0363 (3) | |
H5 | 0.5740 | 0.2456 | 0.8557 | 0.044* | |
C6 | 0.38937 (16) | 0.23627 (19) | 0.82225 (9) | 0.0355 (3) | |
H6 | 0.3656 | 0.2031 | 0.8737 | 0.043* | |
C7 | 0.30345 (13) | 0.26225 (18) | 0.75471 (8) | 0.0287 (3) | |
C8 | 0.12638 (13) | 0.28335 (19) | 0.67489 (9) | 0.0304 (3) | |
C9 | 0.68418 (15) | 0.3366 (2) | 0.72713 (11) | 0.0434 (4) | |
H9A | 0.6941 | 0.3692 | 0.6708 | 0.065* | |
H9B | 0.7301 | 0.2331 | 0.7408 | 0.065* | |
H9C | 0.7165 | 0.4252 | 0.7648 | 0.065* | |
C10 | −0.01086 (15) | 0.2761 (3) | 0.65979 (11) | 0.0452 (4) | |
H10A | −0.0380 | 0.3087 | 0.6030 | 0.068* | |
H10B | −0.0466 | 0.3527 | 0.6972 | 0.068* | |
H10C | −0.0388 | 0.1622 | 0.6691 | 0.068* | |
C11 | 0.29473 (12) | 0.25559 (17) | 0.47850 (7) | 0.0236 (3) | |
C12 | 0.38520 (14) | 0.34425 (18) | 0.44408 (8) | 0.0297 (3) | |
H12 | 0.3893 | 0.4622 | 0.4493 | 0.036* | |
C13 | 0.46993 (15) | 0.2599 (2) | 0.40181 (9) | 0.0365 (3) | |
H13 | 0.5331 | 0.3197 | 0.3788 | 0.044* | |
C14 | 0.46160 (15) | 0.0895 (2) | 0.39362 (9) | 0.0363 (3) | |
H14 | 0.5183 | 0.0315 | 0.3639 | 0.044* | |
C15 | 0.37125 (14) | 0.00203 (19) | 0.42834 (9) | 0.0338 (3) | |
H15 | 0.3675 | −0.1159 | 0.4225 | 0.041* | |
C16 | 0.28551 (13) | 0.08234 (18) | 0.47168 (8) | 0.0285 (3) | |
C17 | 0.18974 (17) | −0.0156 (2) | 0.50997 (12) | 0.0464 (4) | |
H17A | 0.2083 | −0.0119 | 0.5698 | 0.070* | |
H17B | 0.1907 | −0.1318 | 0.4914 | 0.070* | |
H17C | 0.1075 | 0.0326 | 0.4938 | 0.070* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.02608 (18) | 0.03273 (19) | 0.02139 (17) | 0.00435 (12) | 0.00261 (12) | 0.00056 (12) |
O1 | 0.0357 (6) | 0.0446 (6) | 0.0266 (5) | −0.0031 (5) | 0.0128 (4) | 0.0039 (4) |
O2 | 0.0555 (7) | 0.0288 (5) | 0.0317 (5) | 0.0098 (5) | 0.0130 (5) | 0.0029 (4) |
C1 | 0.0253 (6) | 0.0285 (6) | 0.0219 (6) | 0.0001 (5) | 0.0053 (5) | 0.0000 (5) |
C2 | 0.0290 (6) | 0.0229 (6) | 0.0194 (6) | 0.0002 (5) | 0.0046 (5) | −0.0003 (4) |
C3 | 0.0266 (6) | 0.0280 (6) | 0.0220 (6) | −0.0007 (5) | 0.0026 (5) | −0.0005 (5) |
C4 | 0.0314 (7) | 0.0304 (7) | 0.0292 (7) | 0.0008 (5) | −0.0014 (6) | −0.0019 (5) |
C5 | 0.0433 (8) | 0.0393 (8) | 0.0238 (7) | 0.0031 (6) | −0.0064 (6) | 0.0009 (6) |
C6 | 0.0515 (9) | 0.0353 (8) | 0.0198 (6) | 0.0018 (7) | 0.0052 (6) | 0.0032 (5) |
C7 | 0.0331 (7) | 0.0312 (7) | 0.0230 (6) | −0.0009 (5) | 0.0084 (5) | 0.0008 (5) |
C8 | 0.0289 (7) | 0.0362 (7) | 0.0275 (7) | −0.0020 (5) | 0.0089 (5) | −0.0005 (5) |
C9 | 0.0293 (8) | 0.0558 (10) | 0.0424 (9) | −0.0019 (7) | −0.0066 (7) | −0.0019 (7) |
C10 | 0.0281 (8) | 0.0646 (11) | 0.0451 (9) | −0.0056 (7) | 0.0132 (7) | −0.0002 (8) |
C11 | 0.0245 (6) | 0.0286 (7) | 0.0171 (5) | 0.0019 (5) | 0.0003 (5) | −0.0007 (4) |
C12 | 0.0344 (7) | 0.0309 (7) | 0.0249 (6) | −0.0023 (5) | 0.0073 (5) | −0.0004 (5) |
C13 | 0.0363 (8) | 0.0450 (9) | 0.0304 (7) | 0.0001 (6) | 0.0128 (6) | 0.0006 (6) |
C14 | 0.0373 (8) | 0.0457 (9) | 0.0263 (7) | 0.0124 (7) | 0.0049 (6) | −0.0039 (6) |
C15 | 0.0418 (8) | 0.0299 (7) | 0.0285 (7) | 0.0069 (6) | −0.0015 (6) | −0.0039 (5) |
C16 | 0.0313 (7) | 0.0300 (7) | 0.0232 (6) | −0.0014 (5) | −0.0011 (5) | −0.0005 (5) |
C17 | 0.0526 (10) | 0.0321 (8) | 0.0570 (11) | −0.0126 (7) | 0.0168 (8) | −0.0016 (7) |
S1—O2 | 1.4918 (11) | C9—H9B | 0.9800 |
S1—C1 | 1.7580 (13) | C9—H9C | 0.9800 |
S1—C11 | 1.7982 (13) | C10—H10A | 0.9800 |
O1—C8 | 1.3671 (18) | C10—H10B | 0.9800 |
O1—C7 | 1.3789 (17) | C10—H10C | 0.9800 |
C1—C8 | 1.3604 (18) | C11—C12 | 1.3846 (19) |
C1—C2 | 1.4476 (18) | C11—C16 | 1.3955 (19) |
C2—C7 | 1.3932 (17) | C12—C13 | 1.390 (2) |
C2—C3 | 1.3934 (18) | C12—H12 | 0.9500 |
C3—C4 | 1.3912 (19) | C13—C14 | 1.375 (2) |
C3—H3 | 0.9500 | C13—H13 | 0.9500 |
C4—C5 | 1.406 (2) | C14—C15 | 1.381 (2) |
C4—C9 | 1.504 (2) | C14—H14 | 0.9500 |
C5—C6 | 1.380 (2) | C15—C16 | 1.393 (2) |
C5—H5 | 0.9500 | C15—H15 | 0.9500 |
C6—C7 | 1.379 (2) | C16—C17 | 1.498 (2) |
C6—H6 | 0.9500 | C17—H17A | 0.9800 |
C8—C10 | 1.481 (2) | C17—H17B | 0.9800 |
C9—H9A | 0.9800 | C17—H17C | 0.9800 |
O2—S1—C1 | 108.82 (6) | H9A—C9—H9C | 109.5 |
O2—S1—C11 | 105.97 (6) | H9B—C9—H9C | 109.5 |
C1—S1—C11 | 99.66 (6) | C8—C10—H10A | 109.5 |
C8—O1—C7 | 106.61 (10) | C8—C10—H10B | 109.5 |
C8—C1—C2 | 107.12 (12) | H10A—C10—H10B | 109.5 |
C8—C1—S1 | 121.27 (11) | C8—C10—H10C | 109.5 |
C2—C1—S1 | 131.55 (10) | H10A—C10—H10C | 109.5 |
C7—C2—C3 | 118.78 (12) | H10B—C10—H10C | 109.5 |
C7—C2—C1 | 104.68 (11) | C12—C11—C16 | 121.69 (12) |
C3—C2—C1 | 136.54 (12) | C12—C11—S1 | 116.82 (10) |
C4—C3—C2 | 119.30 (13) | C16—C11—S1 | 121.19 (10) |
C4—C3—H3 | 120.3 | C11—C12—C13 | 119.74 (14) |
C2—C3—H3 | 120.3 | C11—C12—H12 | 120.1 |
C3—C4—C5 | 119.29 (13) | C13—C12—H12 | 120.1 |
C3—C4—C9 | 121.04 (14) | C14—C13—C12 | 119.48 (14) |
C5—C4—C9 | 119.67 (14) | C14—C13—H13 | 120.3 |
C6—C5—C4 | 122.77 (13) | C12—C13—H13 | 120.3 |
C6—C5—H5 | 118.6 | C13—C14—C15 | 120.36 (14) |
C4—C5—H5 | 118.6 | C13—C14—H14 | 119.8 |
C7—C6—C5 | 115.96 (13) | C15—C14—H14 | 119.8 |
C7—C6—H6 | 122.0 | C14—C15—C16 | 121.67 (14) |
C5—C6—H6 | 122.0 | C14—C15—H15 | 119.2 |
O1—C7—C6 | 125.53 (13) | C16—C15—H15 | 119.2 |
O1—C7—C2 | 110.59 (12) | C15—C16—C11 | 117.05 (13) |
C6—C7—C2 | 123.88 (14) | C15—C16—C17 | 120.63 (14) |
C1—C8—O1 | 110.99 (12) | C11—C16—C17 | 122.31 (13) |
C1—C8—C10 | 133.48 (14) | C16—C17—H17A | 109.5 |
O1—C8—C10 | 115.53 (12) | C16—C17—H17B | 109.5 |
C4—C9—H9A | 109.5 | H17A—C17—H17B | 109.5 |
C4—C9—H9B | 109.5 | C16—C17—H17C | 109.5 |
H9A—C9—H9B | 109.5 | H17A—C17—H17C | 109.5 |
C4—C9—H9C | 109.5 | H17B—C17—H17C | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6···O2i | 0.95 | 2.45 | 3.3772 (18) | 166 |
C17—H17B···O2ii | 0.98 | 2.55 | 3.458 (2) | 154 |
Symmetry codes: (i) −x+1/2, y−1/2, −z+3/2; (ii) x, y−1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C6—H6···O2i | 0.95 | 2.45 | 3.3772 (18) | 165.5 |
C17—H17B···O2ii | 0.98 | 2.55 | 3.458 (2) | 153.9 |
Symmetry codes: (i) −x+1/2, y−1/2, −z+3/2; (ii) x, y−1, z. |
Acknowledgements
This work was supported by a Dongeui University Grant (2015AA019). The X-ray centre of the Gyeongsang National University is acknowledged for providing access to the single-crystal diffractometer.
References
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Benzofuran derivatives show interesting pharmacological properties such as antibacterial and antifungal, antitumor and antiviral, antimicrobial activities (Aslam et al. 2009; Galal et al., 2009; Wahab Khan et al., 2005), and potential inhibitor of β-amyloid aggregation (Howlett et al., 1999; Ono et al., 2002). These benzofuran compounds occur in a great number of natural products. (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our continuing project on benzofuran derivatives (Choi et al., 2012), 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 0.009 (1) Å from the least-squares plane defined by the nine constituent atoms. The 2-methylphenyl ring is essentially planar, with a mean deviation of 0.004 (1) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring and the 2-methylphenyl ring is 86.72 (4)°. In the crystal, molecules are linked into a chain along the b axis direction by C—H···O hydrogen bonds (Table 1 and Fig. 2). These molecules are connected on either side of this chain by further C—H···O hydrogen bonds (Table 1 and Fig. 2).