5-Ethyl-3-(3-fluoro­phenyl­sulfon­yl)-2-methyl-1-benzofuran

Hong Dae Choi; Pil Ja Seo; Byeng Wha Son; Uk Lee

doi:10.1107/S1600536811015443

. 2011 Apr 29;67(Pt 5):o1278. doi: 10.1107/S1600536811015443

5-Ethyl-3-(3-fluorophenylsulfonyl)-2-methyl-1-benzofuran

Hong Dae Choi ^a, Pil Ja Seo ^a, Byeng Wha Son ^b, Uk Lee ^b,^*

PMCID: PMC3089223 PMID: 21754560

Abstract

In the title compound, C₁₇H₁₅FO₃S, the fluorophenyl ring makes a dihedral angle of 76.11 (5)° with the mean plane of the benzofuran fragment. In the crystal, molecules are linked by weak intermolecular C—H⋯O hydrogen bonds and C—H⋯π interactions.

Related literature

For the biological 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 structural studies of related 5-alkyl-3-(4-fluorophenylsulfonyl)-2-methyl-1-benzofurans, see: Choi et al. (2010a ▶,b ▶,c ▶).

Experimental

Crystal data

C₁₇H₁₅FO₃S
M _r = 318.35
Orthorhombic,
a = 8.4395 (1) Å
b = 11.3701 (2) Å
c = 15.3559 (2) Å
V = 1473.52 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 173 K
0.35 × 0.25 × 0.16 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.920, T _max = 0.962
14844 measured reflections
3665 independent reflections
3453 reflections with I > 2σ(I)
R _int = 0.035

Refinement

R[F ² > 2σ(F ²)] = 0.032
wR(F ²) = 0.077
S = 1.09
3665 reflections
200 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.30 e Å⁻³
Absolute structure: Flack (1983 ▶), 1555 Friedel pairs
Flack parameter: −0.01 (6)

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: 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.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811015443/bh2350sup1.cif

e-67-o1278-sup1.cif^{(18.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811015443/bh2350Isup2.hkl

e-67-o1278-Isup2.hkl^{(179.7KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536811015443/bh2350Isup3.cml

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

Table 1. Hydrogen-bond geometry (Å, °).

Cg is the centroid of the C2–C7 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O2ⁱ	0.95	2.49	3.206 (2)	133
C13—H13⋯O3ⁱⁱ	0.95	2.51	3.395 (2)	155
C9—H9A⋯Cgⁱⁱⁱ	0.99	2.68	3.625 (2)	159

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) .

supplementary crystallographic information

Comment

Many compounds having a benzofuran skeleton exhibit interesting biological properties such as antibacterial and antifungal, antitumor and antiviral, and antimicrobial activities (Aslam et al., 2009; Galal et al., 2009; Khan et al., 2005). These compounds occur in a wide range of natural products (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing study of the substituent effect on the solid state structures of 5-alkyl-3-(4-fluorophenylsulfonyl)-2-methyl-1-benzofuran analogues (Choi et al., 2010a,b,c), we report herein on the molecular and crystal structures of the title compound.

The title compound crystallizes in the non-centrosymmetric space group P2₁2₁2₁ in spite of having no asymmetric C atoms.

In the title compound (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.017 (1) Å from the least-squares plane defined by the nine constituent atoms. The 3-fluorophenyl ring makes a dihedral angle of 76.11 (5)° with the mean plane of the benzofuran fragment. The crystal packing (Fig. 2) is stabilized by weak intermolecular C–H···O hydrogen bonds; the first one between a benzene H atom and the O atom of the sulfonyl group (Table 1; C6–H6···O2ⁱ), and the second one between a 3-fluorophenyl H atom and the O atom of the sulfonyl (Table 1; C13–H13···O3ⁱⁱ). The crystal packing (Fig. 3) is further stabilized by intermolecular C–H···π interactions between a methylene H atom of the ethyl group and the benzene ring (Table 1; C9–H9A···Cgⁱⁱⁱ, Cg is the centroid of the C2···C7 benzene ring).

Experimental

77% 3-Chloroperoxybenzoic acid (560 mg, 2.5 mmol) was added in small portions to a stirred solution of 5-ethyl-3-(3-fluorophenylsulfanyl)-2-methyl-1-benzofuran (320 mg, 1.2 mmol) in dichloromethane (40 mL) at 273 K. After being stirred at room temperature for 6 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 column chromatography (hexane-ethyl acetate, 4:1 v/v) to afford the title compound as a colorless solid [yield 71%, m.p. 395-396 K; R_f = 0.51 (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 diisopropyl ether at room temperature.