3-Ethyl­sulfinyl-2-(4-fluoro­phen­yl)-5-iodo-1-benzofuran

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

doi:10.1107/S1600536810012717

. 2010 Apr 10;66(Pt 5):o1043. doi: 10.1107/S1600536810012717

3-Ethylsulfinyl-2-(4-fluorophenyl)-5-iodo-1-benzofuran

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

PMCID: PMC2979084 PMID: 21579104

Abstract

In the title compound, C₁₆H₁₂FIO₂S, the 4-fluorophenyl ring is rotated slightly out of the benzofuran plane, as indicated by the dihedral angle of 4.48 (5)°. In the crystal structure, pairs of I⋯O halogen bonds [I⋯O = 3.123 (1) Å] link the molecules into centrosymmetric dimers. These dimers are further linked via aromatic π–π interactions between the benzene and 4-fluorophenyl rings of neighbouring molecules [centroid–centroid distance = 3.620 (3) Å].

Related literature

For the crystal structures of similar 3-ethylsulfinyl-2-(4-fluorophenyl)-5-halo-1-benzofuran derivatives, see: Choi et al. (2010a ▶,b ▶,c ▶). 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 a review of halogen bonding, see: Politzer et al. (2007 ▶).

Experimental

Crystal data

C₁₆H₁₂FIO₂S
M _r = 414.22
Triclinic,
a = 7.2942 (4) Å
b = 9.6312 (5) Å
c = 11.0132 (6) Å
α = 100.637 (2)°
β = 97.947 (2)°
γ = 105.086 (2)°
V = 719.91 (7) Å³
Z = 2
Mo Kα radiation
μ = 2.38 mm⁻¹
T = 173 K
0.38 × 0.18 × 0.11 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.548, T _max = 0.746
12738 measured reflections
3342 independent reflections
3237 reflections with I > 2σ(I)
R _int = 0.029

Refinement

R[F ² > 2σ(F ²)] = 0.019
wR(F ²) = 0.052
S = 1.11
3342 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.63 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 datablocks global, I. DOI: 10.1107/S1600536810012717/ds2026sup1.cif

e-66-o1043-sup1.cif^{(18.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810012717/ds2026Isup2.hkl

e-66-o1043-Isup2.hkl^{(163.9KB, hkl)}

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

supplementary crystallographic information

Comment

Compounds containing benzofuran moiety show interesting pharmacological activities such as antifungal (Aslam et al., 2006), antitumor and antiviral (Galal et al., 2009), antimicrobial (Khan et al., 2005) properties. These compounds are widely occurring in nature (Akgul & Anil, 2003; Soekamto et al., 2003). As a part of our ongoing studies of the effect of side chain substituents on the solid state structures of 3-ethylsulfinyl-2-(4-fluorophenyl)-5-halo-1-benzofuran analogues (Choi et al., 2010a,b,c), we report the crystal structure of the title compound (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 dihedral angle formed by the benzofuran plane and the 4-fluorophenyl ring is 4.48 (5)°. The crystal packing (Fig. 2) is stabilized by I···O halogen bondings between the iodine and the oxygen of the S═O unit [I···O2ⁱ = 3.123 (1) Å; C–I···O2ⁱ = 167.88 (5)°] (Politzer et al., 2007). The molecular packing (Fig. 2) is further stabilized by aromatic π–π interactions between the benzene and the 4-fluorophenyl rings of adjacent molecules, with a Cg1···Cg2ⁱⁱ distance of 3.620 (3) Å (Cg1 and Cg2 are the centroids of the the C2-C7 benzene ring and the C9-C14 4-fluorophenyl ring, respectively).

Experimental

77% 3-Chloroperoxybenzoic acid (202 mg, 0.9 mmol) was added in small portions to a stirred solution of 3-ethylsulfanyl-2-(4-fluorophenyl)-5-iodo-1-benzofuran (358 mg, 0.9 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 4h, 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 80%, m.p. 446-447 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 chloroform at room temperature.