5-Bromo-3-cyclo­pentyl­sulfinyl-2,7-dimethyl-1-benzofuran

Hong Dae Choi; Pil Ja Seo; Uk Lee

doi:10.1107/S1600536811056091

. 2012 Jan 14;68(Pt 2):o373. doi: 10.1107/S1600536811056091

5-Bromo-3-cyclopentylsulfinyl-2,7-dimethyl-1-benzofuran

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

PMCID: PMC3275051 PMID: 22346996

Abstract

In the title compound, C₁₅H₁₇BrO₂S, the cyclopentyl ring adopts an envelope conformation. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds. A slipped π–π interaction occurs between the furan and benzene rings of adjacent molecules [centroid–centroid distance = 3.892 (3) Å and slippage = 1.786 (3) Å]. The crystal structure also exhibits a weak C—Br⋯π [2.919 (3) Å] interaction.

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 the crystal structures of related compounds, see: Choi et al. (2011a ▶,b ▶).

Experimental

Crystal data

C₁₅H₁₇BrO₂S
M _r = 341.26
Orthorhombic,
a = 19.5624 (8) Å
b = 8.3501 (4) Å
c = 17.5346 (7) Å
V = 2864.2 (2) Å³
Z = 8
Mo Kα radiation
μ = 3.01 mm⁻¹
T = 173 K
0.36 × 0.19 × 0.04 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.414, T _max = 0.899
14696 measured reflections
3561 independent reflections
2232 reflections with I > 2σ(I)
R _int = 0.052

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.094
S = 1.01
3561 reflections
174 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.51 e Å⁻³

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 datablock(s) global, I. DOI: 10.1107/S1600536811056091/xu5434sup1.cif

e-68-0o373-sup1.cif^{(24.1KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811056091/xu5434Isup2.hkl

e-68-0o373-Isup2.hkl^{(174.7KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536811056091/xu5434Isup3.cml

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

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O2ⁱ	0.95	2.60	3.465 (3)	152
C9—H9B⋯O2ⁱ	0.98	2.55	3.489 (3)	161
C10—H10B⋯O1ⁱⁱ	0.98	2.60	3.480 (3)	149

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

Acknowledgments

This work was supported by the Blue-Bio Industry Regional Innovation Center (RIC08-06-07) at Dongeui University as an RIC program under the Ministry of Knowledge Economy and Busan City.

supplementary crystallographic information

Comment

Benzofuran derivatives have drawn much interest in view of their valuable 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 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 5-bromo-2,7-dimethyl-1-benzofuran derivatives containing either 3-cyclohexylsulfinyl (Choi et al., 2011a) or 3-cyclohexylsulfonyl (Choi et al., 2011b) substituents, we report herein the crystal structure of the title compound.

In the title molecule (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.020 (1) Å from the least-squares plane defined by the nine constituent atoms. The cyclopentyl ring is in the envelope form. The crystal packing (Fig. 2) is stabilized by weak intermolecular C–H···O hydrogen bonds (see, Table 1). The crystal packing (Fig. 3) is further stabilized by a weak intermolecular C—Br···π interaction between the bromine and the benzene ring of an adjacent molecule, with a C4—Br1···Cg2ⁱⁱ [2.919 (3) Å] (Cg2 is the centroid of the C2-C7 benzene ring). The crystal packing (Fig. 3) also exhibits a weak slipped π···π interaction between the furan and benzene rings of adjacent molecules, with a Cg1···Cg2ⁱ distance of 3.892 (4) Å and an interplanar distance of 3.458 (3) Å resulting in a slippage of 1.786 (3) Å (Cg1 is the centroid of the C1/C2/C7/O1/C8 furan ring).

Experimental

77% 3-chloroperoxybenzoic acid (202 mg, 0.9 mmol) was added in small portions to a stirred solution of 5-bromo-3-cyclopentylsulfanyl-2,7-dimethyl-1-benzofuran (260 mg, 0.8 mmol) in dichloromethane (30 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, 1:1 v/v) to afford the title compound as a colorless solid [yield 67%, m.p. 415–416 K; R_f = 0.51 (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 benzene at room temperature.