5-Bromo-2-(4-fluorophenyl)-3-methylsulfinyl-1-benzofuran

In the title compound, C15H10BrFO2S, the O atom and the methyl group of the methylsulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment. The 4-fluorophenyl ring is rotated out of the benzofuran plane, as indicated by a dihedral angle of 26.23 (5)°. The crystal structure is stabilized by a non-classical intermolecular C—H⋯O hydrogen bond and a Br⋯O halogen bond [3.163 (2) Å].

In the title compound, C 15 H 10 BrFO 2 S, the O atom and the methyl group of the methylsulfinyl substituent are located on opposite sides of the plane through the benzofuran fragment. The 4-fluorophenyl ring is rotated out of the benzofuran plane, as indicated by a dihedral angle of 26.23 (5) . The crystal structure is stabilized by a non-classical intermolecular C-HÁ Á ÁO hydrogen bond and a BrÁ Á ÁO halogen bond [3.163 (2) Å ].
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: OM2304).

Comment
Molecules including benzofuran moiety are of considerable interest due to a variety of their pharmacological activities (Howlett et al., 1999;Twyman & Allsop, 1999) and these compounds are occurring in natural products (Akgul & Anil, 2003;Soekamto et al., 2003). As a part of our continuing studies of the effect of side chain substituents on the solid state structures of 2-(4-fluorophenyl)-3-methylsulfinyl-1-benzofuran analogues (Choi et al., 2009a, b), we report the crystal structure of the title compound (Fig. 1).
The benzofuran unit is essentially planar, with a mean deviation of 0.010 (2) Å from the least-squares plane defined by the nine constituent atoms. The dihedral angle formed by the plane of the benzofuran and the 4-fluorophenyl ring is 26.23 (5)Å. The crystal packing ( Fig. 2) is stabilized by a non-classical intermolecular C-H···O hydrogen bond between the 4-fluorophenyl H atom and the oxygen of the S═O unit, with a C14-H14···O2 i (Table 1), and a Br···O halogen bond between the bromine and the oxygen of the S═O unit [Br···O2 ii = 3.163 (2) Å; C-Br···O2 ii = 173.37 (7)°] (Politzer et al., 2007).

Experimental
77% 3-Chloroperoxybenzoic acid (179 mg, 0.8 mmol) was added in small portions to a stirred solution of 5-bromo-2-(4fluorophenyl)-3-methylsulfanyl-1-benzofuran (270 mg, 0.8 mmol) in dichloromethane (20 mL) at 273 K. After being stirred at room temperature for 3h, 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 (hexane-ethyl acetate, 1:1 v/v) to afford the title compound as a colorless solid [yield 87%, m.p. 498-499 K; R f = 0.6 (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 chloroforrm at room temperature.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 Å for aromatic H atoms and 0.96 Å for methyl H atoms, and with U iso (H) = 1.2U eq (C) for aromatic H atoms and 1.5U eq (C) for methyl H atoms. Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.

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.