5-Bromo-2-phenyl-3-phenylsulfinyl-1-benzofuran

In the title compound, C20H13BrO2S, the O atom and the phenyl group of the phenylsulfinyl substituent are located on opposite sides of the plane of the benzofuran system. The S-bound phenyl ring is almost perpendicular to this plane [80.35 (8)°]. The phenyl ring in the 2-position is twisted with respect to the benzofuran plane, making a dihedral angle of 16.0 (1)°.

In the title compound, C 20 H 13 BrO 2 S, the O atom and the phenyl group of the phenylsulfinyl substituent are located on opposite sides of the plane of the benzofuran system. The Sbound phenyl ring is almost perpendicular to this plane [80.35 (8) ]. The phenyl ring in the 2-position is twisted with respect to the benzofuran plane, making a dihedral angle of 16.0 (1) .
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: DN2491).

Comment
Molecules containing benzofuran moiety have received much attenttion in the field of their pharmacological properties (Howlett et al., 1999;Twyman & Allsop, 1999), and these compounds are ubiquitous in nature (Akgul & Anil, 2003;Reuss & König, 2004). As a part of our ongoing studies of the effect of side chain substituents on the solid state structures of 5-halo-2-phenyl-3-phenylsulfinyl-1-benzofuran analogues (Choi et al., 2009a,b), we present 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 unit and the plane of 2-phenyl ring is 16.0 (1)°. The phenyl ring (C15-C20) is almost perpendicular to the plane of the benzofuran unit [80.35 (8)°].
Experimental 77% 3-Chloroperoxybenzoic acid (224 mg, 1.0 mmol) was added in small portions to a stirred solution of 5-bromo-2-phenyl-3-phenylsulfanyl-1-benzofuran (343 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 in vacuum. The residue was purified by column chromatography (hexane-ethyl acetate, 2 : 1 v/v) to afford the title compound as a colorless solid [yield 73%, m.p. 417-418 K; R f = 0.56 (hexane-ethyl acetate, 2 : 1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in benzene at room temperature.

Refinement
All H atoms were fixed geometrically and treated as riding with C-H = 0.93 Å and U iso (H) = 1.2U eq (C) Figures   Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radii.

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. 119.6 (2) C19-C20-H20 120.3 C11-C10-C9 120.6 (3) C15-C20-H20 120.3