5-Bromo-3-ethylsulfinyl-7-methyl-2-(4-methylphenyl)-1-benzofuran

In the title compound, C18H17BrO2S, the dihedral angle between the mean planes of the benzofuran and 4-methylphenyl rings is 14.54 (5)°. In the crystal, molecules are linked via pairs of π–π interactions between the benzene and 4-methylphenyl rings, with centroid–centroid distances of 3.811 (3) and 3.755 (3) Å. A similar interaction is found between the furan and 4-methylphenyl rings, with a centroid–centroid distance of 3.866 (3) Å between neighbouring molecules. The molecules are stacked along the a-axis direction. In addition, a short Br⋯O contact distance of 3.128 (2) Å is observed between inversion-related dimers.

In the title compound, C 18 H 17 BrO 2 S, the dihedral angle between the mean planes of the benzofuran and 4-methylphenyl rings is 14.54 (5) . In the crystal, molecules are linked via pairs ofinteractions between the benzene and 4methylphenyl rings, with centroid-centroid distances of 3.811 (3) and 3.755 (3) Å . A similar interaction is found between the furan and 4-methylphenyl rings, with a centroidcentroid distance of 3.866 (3) Å between neighbouring molecules. The molecules are stacked along the a-axis direction. In addition, a short BrÁ Á ÁO contact distance of 3.128 (2) Å is observed between inversion-related dimers.
Supporting information for this paper is available from the IUCr electronic archives (Reference: FJ2667).
In the title molecule ( Fig. 1), the benzofuran ring system is essentially planar, with a mean deviation of 0.017 (2) Å from the least-squares plane defined by the nine constituent atoms. The 4-methylphenyl ring is essentially planar, with a mean deviation of 0.004 (1) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring system and the 4-methylphenyl ring is 14.54 (5)°.
In the crystal structure (Fig. 2), the molecules are linked via π-π interactions between the benzene and 4-methylphenyl rings, and the furan and 4-methylphenyl rings of neighbouring molecules. The molecules stack along the a-axis direction.
After being stirred at room temperature for 5h, 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

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 methylene and 0.98 Å for methyl H atoms, respectively. U iso (H) = 1.2U eq (C) for aryl and methylene, and 1.5U eq (C) for methyl H atoms. The positions of methyl hydrogens were optimized using the SHELXL-97's command AFIX 137 (Sheldrick, 2008).

Figure 1
The molecular structure of the title molecule with the atom numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. The hydrogen atoms are presented as small spheres of arbitrary radius.

Figure 2
A view of the Br···O and π-π interactions (dotted lines) in the crystal structure of the title compound. The H-atoms were omitted for clarity. [Symmetry codes: (i)-x + 2, -y + 1, -z + 2; (ii) -x + 1, -y + 1, -z + 1; (iii) -x + 2, -y + 1, -z + 1.] supplementary materials sup-3 Acta Cryst. (2014). E70, o461  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.