2,5-Bis(4-fluoro­phen­yl)-2-methyl­sulfanyl-1-benzofuran

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

doi:10.1107/S1600536811007458

. 2011 Mar 5;67(Pt 4):o782. doi: 10.1107/S1600536811007458

2,5-Bis(4-fluorophenyl)-2-methylsulfanyl-1-benzofuran

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

PMCID: PMC3099888 PMID: 21754073

Abstract

The crystal studied of the title compound, C₂₁H₁₄F₂OS, was an inversion twin with a 0.67 (8):0.33 (8) domain ratio. The 4-fluorophenyl ring in the 2-position makes a dihedral angle of 25.14 (6)° with the mean plane of the benzofuran fragment, and the dihedral angle between 4-fluorophenyl ring in the 5-position and the mean plane of the benzofuran fragment is 28.50 (7)°. In the crystal, molecules are linked through weak intermolecular C—H⋯F and C—H⋯π interactions.

Related literature

For the pharmacological activity of benzofuran compounds, see: Aslam et al. (2006 ▶); 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 3-alkylsulfanyl-2-(4-fluorophenyl)-5-phenyl-1-benzofuran derivatives, see: Choi et al. (2009 ▶, 2010 ▶).

Experimental

Crystal data

C₂₁H₁₄F₂OS
M _r = 352.38
Monoclinic,
a = 10.7673 (7) Å
b = 7.2986 (5) Å
c = 11.5145 (8) Å
β = 116.124 (1)°
V = 812.44 (10) Å³
Z = 2
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 173 K
0.32 × 0.29 × 0.13 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.930, T _max = 0.972
7891 measured reflections
3710 independent reflections
3501 reflections with I > 2σ(I)
R _int = 0.023

Refinement

R[F ² > 2σ(F ²)] = 0.038
wR(F ²) = 0.101
S = 1.06
3710 reflections
228 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.21 e Å⁻³
Absolute structure: Flack (1983 ▶), 1700 Friedel pairs
Flack parameter: 0.33 (8)

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/S1600536811007458/sj5110sup1.cif

e-67-0o782-sup1.cif^{(19.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811007458/sj5110Isup2.hkl

e-67-0o782-Isup2.hkl^{(181.9KB, hkl)}

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

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

Cg is the centroid of the C15–C20 4-fluorophenyl ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯F1ⁱ	0.95	2.45	3.322 (2)	153
C10—H10⋯Cgⁱⁱ	0.95	2.67	3.441 (2)	139
C17—H17⋯Cgⁱⁱⁱ	0.95	2.86	3.557 (2)	131

Open in a new tab

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

supplementary crystallographic information

Comment

Many compounds having a benzofuran ring system exhibit interesting pharmacological properties such as antifungal, antitumor and antiviral, and antimicrobial activities (Aslam et al., 2006, 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 substituent effects on the solid state structures of 3-alkylsulfanyl-2-(4-fluorophenyl)-5-phenyl-1-benzofuran analogues (Choi et al., 2009, 2010), we report herein on the crystal structure of the title compound.

The title compound crystallizes as the non-centrosymmetric space group P2₁ in spite of having no asymmetric C atoms. The crystal studied was an inversion twin with a 0.33 (8) : 0.67 (8) domain ratio.

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. In the crystal structure, the dihedral angle formed by the 4-fluorophenyl ring (C15–C20) and the mean plane of the benzofuran fragment is 25.14 (6)°, and the (C9–C14) 4-fluorophenyl ring makes a dihedral angle of 28.50 (7)° with the mean plane of the benzofuran fragment. The molecular packing (Fig. 2) is stabilized by weak intermolecular C—H···F hydrogen bonds between a benzene H atom and the F atom of the (C9–C14) 4-fluorophenyl ring (Table 1; C6—H6···F1ⁱ). The molecular packing (Fig. 3) also exhibits intermolecular C—H···π interactions; the first one between a 4-fluorophenyl H atom in the 5-position and the (C15–C20) 4-fluorophenyl ring (Table 1; C10–H10···Cgⁱⁱ), and the second one between the 4-fluorophenyl H atom in the 2-position and the (C15–C20) 4-fluorophenyl ring (Table 1; C17—H17···Cgⁱⁱⁱ) (Cg is the centroid of the C15–C20 4-fluorophenyl ring).

Experimental

Zinc chloride (245 mg, 1.8 mmol) was added to a stirred solution of 4-fluoro-4'-hydroxybiphenyl (339 mg, 1,8 mmol) and 2-chloro-4'-fluoro-2-methylsulfanylacetophenone (395 mg, 1.8 mmol) in dichloromethane (30 mL) at room temperature, and stirring was continued at the same temperature for 40 min. The reaction was quenched by the addition of water and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (carbon tetrachloride) to afford the title compound as a colorless solid [yield 65%, m.p. 438–439 K; Rf = 0.69 (carbon tetrachloride)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in acetone at room temperature.