2-(2-Fluorophenyl)-5-iodo-7-methyl-3-methylsulfinyl-1-benzofuran

In the title compound, C16H12FIO2S, the dihedral angle between the plane of the benzofuran ring system (r.m.s. deviation = 0.023 Å) and that of the 2-fluorophenyl ring is 39.78 (7)°. In the crystal, molecules are linked via pairs of I⋯π contacts [3.812 (2) Å] and a π–π interaction between the benzene rings of neighbouring molecules [centroid–centroid distance = 3.821 (2) Å] into inversion dimers. These dimers are further linked by π–π interactions between the furan and benzene rings of neighbouring molecules [centroid–centroid distance = 3.668 (2) Å]. The molecules stack along the a-axis direction. In addition, C—H⋯O hydrogen bonds are observed between inversion-related dimers.

In the title compound, C 16 H 12 FIO 2 S, the dihedral angle between the plane of the benzofuran ring system (r.m.s. deviation = 0.023 Å ) and that of the 2-fluorophenyl ring is 39.78 (7) . In the crystal, molecules are linked via pairs of IÁ Á Á contacts [3.812 (2) Å ] and ainteraction between the benzene rings of neighbouring molecules [centroid-centroid distance = 3.821 (2) Å ] into inversion dimers. These dimers are further linked byinteractions between the furan and benzene rings of neighbouring molecules [centroid-centroid distance = 3.668 (2) Å ]. The molecules stack along the a-axis direction. In addition, C-HÁ Á ÁO hydrogen bonds are observed between inversion-related dimers.
This work was supported by Dong-eui University grant No. 2014AA013.
Supporting information for this paper is available from the IUCr electronic archives (Reference: HB7228).
In the title molecule ( Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.019 (2) Å from the least-squares plane defined by the nine constituent atoms. The 2-fluorophenyl ring is essentially planar, with a mean deviation of 0.012 (2) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring system and the 2-fluorophenyl ring is 39.78 (7)°. In the crystal structure ( Fig. 2), molecules are linked via pairs of C4-I1···π contacts between the iodine atom and the furan ring of a neighbouring molecule with a C4-I1···Cg1 iv = 3.812 (2) Å (Cg1 is the C1/C2/C7/O1/C8 furan ring), and by a π···π interaction between the benzene rings of neighbouring molecules, with a Cg2···Cg2 iv distance of 3.821 (2) Å and an interplanar distance of 3.581 (2) Å resulting in a slippage of 1.333 (2) Å (Cg2 is the C2-C7 benzene ring), into inversion dimers. These dimers are further linked by π···π interactions between the furan and benzene rings of neighbouring molecules, with a Cg1···Cg2 iii distance of 3.668 (2) Å and an interplanar distance of 3.375 (2) Å resulting in a slippage of 1.437 (2) Å. The molecules stack along the a-axis direction. In addition, C-H···O hydrogen bonds (Table 1) are observed between inversion-related dimers.

Experimental
3-Chloroperoxybenzoic acid (77%, 224 mg, 1.0 mmol) was added in small portions to a stirred solution of 2-(2-fluorophenyl)-5-iodo-7-methyl-3-methylsulfanyl-1-benzofuran (358 mg, 0.9 mmol) in dichloromethane (40 mL) at 273 K. After being stirred at room temperature for 6h, 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 Colourless blocks were prepared by slow evaporation of a solution of the title compound in ethyl acetate at room temperature.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.95 Å for aryl, 0.99 Å for methyl H atoms. U iso (H) = 1.2U eq (C) for aryl and 1.5U eq (C) for methyl H atoms. The methyl groups were allowed to rotate, but not to tip, to best fit the electron density.  The molecular structure of the title molecule with displacement ellipsoids drawn at the 50% probability level.

Figure 2
A view of the C-H···O, I···π and π···π interactions (dotted lines) in the crystal structure of the title compound. H atoms non-participating in hydrogen-bonding were omitted for clarity. [Symmetry codes: (i) x -1, -y + 1/2, z -1/2; (ii) x -1, y, z; (iii)-x + 1, -y + 1, -z + 1; (iv) -x + 1, -y + 1, -z + 2; (v) x + 1, -y + 1/2, z + 1/2; (vi) x + 1, y, z.] where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.002 Δρ max = 0.47 e Å −3 Δρ min = −0.56 e Å −3 Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.