5-(4-Bromo­phen­yl)-2-methyl-3-methyl­sulfinyl-1-benzofuran

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

doi:10.1107/S1600536809033509

. 2009 Aug 29;65(Pt 9):o2269. doi: 10.1107/S1600536809033509

5-(4-Bromophenyl)-2-methyl-3-methylsulfinyl-1-benzofuran

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

PMCID: PMC2969963 PMID: 21577664

Abstract

In the title compound, C₁₆H₁₃BrO₂S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment. The 4-bromophenyl ring is rotated out of the benzofuran plane, making a dihedral angle of 39.23 (8)°. The crystal structure exhibits weak non-classical intermolecular C—H⋯O hydrogen bonds and two intermolecular C—H⋯π interactions.

Related literature

For the crystal structures of similar 5-aryl-2-methyl-1-benzofuran derivatives, see: Choi et al. (2006a ▶,b ▶). For the pharmacological activity of benzofuran compounds, see: Howlett et al. (1999 ▶); Twyman & Allsop (1999 ▶). For natural products with benzofuran rings, see: Akgul & Anil (2003 ▶); von Reuss & König (2004 ▶).

Experimental

Crystal data

C₁₆H₁₃BrO₂S
M _r = 349.23
Monoclinic,
a = 11.410 (1) Å
b = 7.9508 (8) Å
c = 15.728 (2) Å
β = 99.399 (1)°
V = 1407.7 (3) Å³
Z = 4
Mo Kα radiation
μ = 3.07 mm⁻¹
T = 173 K
0.30 × 0.30 × 0.20 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2000 ▶) T _min = 0.460, T _max = 0.579
8551 measured reflections
3195 independent reflections
2551 reflections with I > 2σ(I)
R _int = 0.035

Refinement

R[F ² > 2σ(F ²)] = 0.028
wR(F ²) = 0.076
S = 1.04
3195 reflections
183 parameters
H-atom parameters constrained
Δρ_max = 0.52 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); 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/S1600536809033509/zl2233sup1.cif

e-65-o2269-sup1.cif^{(18.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809033509/zl2233Isup2.hkl

e-65-o2269-Isup2.hkl^{(156.8KB, hkl)}

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
C10—H10⋯O2ⁱ	0.93	2.66	3.416 (3)	139
C15—H15B⋯O1ⁱⁱ	0.96	2.66	3.380 (3)	132
C16—H16A⋯O2ⁱ	0.96	2.63	3.463 (3)	145
C13—H13⋯Cg2ⁱⁱⁱ	0.93	2.86	3.624 (3)	140
C16—H16B⋯Cg1^iv	0.96	2.90	3.768 (3)	152

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Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) . Cg1 and Cg2 are the centroids of the C9–C14 phenyl ring and the C1/C2/C7/O2/C8 furan ring, respectively.

supplementary crystallographic information

Comment

Benzofuran ring systems have attracted particular interest in the view of their pharmacological properties (Howlett et al., 1999; Twyman & Allsop, 1999), and these compounds are occurring in natural products (Akgul & Anil, 2003; von Reuss & König, 2004). As a part of our ongoing studies on the synthesis and structures of 5-aryl-2-methyl-1-benzofuran analogues, the crystal structure of 5-(4-bromophenyl)-2-methyl-3-methylsulfanyl-1-benzofuran (Choi et al., 2006a) and 2-methyl-3-methylsulfinyl-5-phenyl-1-benzofuran (Choi et al., 2006b) have been described in the literature. Here we report the crystal structure of the title compound (Fig. 1).

The benzofuran unit is essentially planar, with a mean deviation of 0.005 (2) Å from the least-squares plane defined by the nine constituent atoms. The 4-bromophenyl ring is rotated out of the benzofuran plane, with a dihedral angle of 39.23 (8)°. The molecular packing (Fig. 2) is stabilized by weak non-classical intermolecular C–H···O hydrogen bonds; the first between the 4-bromophenyl H atom and the furan O atom, with C10–H10···O2ⁱ, the second between the methyl H atom and the oxygen of the S═O unit, with C15–H15B···O1ⁱⁱ, the third between the methyl H atom of the methylsulfinyl substituent and the furan O atom, with C16–H16A···O2ⁱ, respectively (Table 1). The crystal packing (Fig. 3) is further stabilized by two intermolecular C–H···π interactions; the first between the 4-bromophenyl H atom and the furan ring of a neighbouring molecule, with C13–H13···Cg2ⁱⁱⁱ, the second between the methyl H atom of the methylsulfinyl substituent and the 4-bromophenyl ring of an adjacent molecule, with C16–H16B···Cg1^iv, respectively (Table 1; Cg1 and Cg2 are the centroids of the C9-C14 phenyl ring and the C1/C2/C7/O2/C8 furan ring, respectively).

Experimental

77% 3-chloroperoxybenzoic acid (247 mg, 1.1 mmol) was added in small portions to a stirred solution of 5-(4-bromophenyl)-2-methyl-3-methylsulfanyl-1-benzofuran (333 mg, 1.0 mmol) in dichloromethane (40 ml) at 273 K. After being stirred for 4 hr at room temperature, the mixture was washed with saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated in vacuum. The residue was purified by column chromatography (ethyl acetate) to afford the title compound as a colorless solid [yield 78%, m.p. 458-459 K; R_f = 0.31 (ethyl acetate)]. Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in acetone at room temperature. Spectroscopic analysis; EI-MS 348 [M⁺], 350 [M+2].