2-(4-Fluorophenyl)-5-iodo-7-methyl-3-methylsulfinyl-1-benzofuran

In the title compound, C16H12FIO2S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane through the benzofuran fragment. The 4-fluorophenyl ring is rotated slightly out of the benzofuran plane, as indicated by the dihedral angle of 7.43 (6)°. In the crystal structure, pairs of short I⋯O [3.074 (2) Å] contacts link the molecules into centrosymmetric dimers. These dimers are further linked via aromatic π–π interactions between the benzene and the 4-fluorophenyl rings of neighbouring molecules [centroid–centroid distance = 3.617 (3) Å].

In the title compound, C 16 H 12 FIO 2 S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane through the benzofuran fragment. The 4fluorophenyl ring is rotated slightly out of the benzofuran plane, as indicated by the dihedral angle of 7.43 (6) . In the crystal structure, pairs of short IÁ Á ÁO [3.074 (2) Å ] contacts link the molecules into centrosymmetric dimers. These dimers are further linked via aromaticinteractions between the benzene and the 4-fluorophenyl rings of neighbouring molecules [centroid-centroid distance = 3.617 (3) Å ].

Experimental
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: VM2030).

Experimental
77% 3-chloroperoxybenzoic acid (269 mg, 1.2 mmol) was added in small portions to a stirred solution of 2-(4-fluorophenyl)-5-iodo-7-methyl-3-methylsulfanyl-1-benzofuran (438 mg, 1.1 mmol) in dichloromethane (35 mL) at 273 K. After being stirred at room temperature for 4hr, 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 77%, m.p. 502-503 K; R f = 0.57 (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 tetrahydrofuran at room temperature.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq I 1.016803 (18)