5-Cyclohexyl-3-(3-fluorophenylsulfonyl)-2-methyl-1-benzofuran

In the title compound, C21H21FO3S, the cyclohexyl ring adopts a chair conformation. The 3-fluorophenyl ring makes a dihedral angle of 79.15 (4)° with the mean plane of the benzofuran fragment. In the crystal, molecules are linked by weak intermolecular C—H⋯O hydrogen bonds and C—H⋯π interactions.

In the title compound, C 21 H 21 FO 3 S, the cyclohexyl ring adopts a chair conformation. The 3-fluorophenyl ring makes a dihedral angle of 79.15 (4) with the mean plane of the benzofuran fragment. In the crystal, molecules are linked by weak intermolecular C-HÁ Á ÁO hydrogen bonds and C-HÁ Á Á interactions.
In the title molecule ( Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.005 (1) Å from the least-squares plane defined by the nine constituent atoms. The 3-fluorophenyl ring makes a dihedral angle of 79.15 (4)°w ith the mean plane of the benzofuran ring. The cyclohexyl ring is in the chair form. The crystal packing (Fig. 2) is stabilized by weak intermolecular C-H···O hydrogen bonds (Table 1; C21-H21···O3 i ). The crystal packing (Fig. 2) is further stabilized by intermolecular C-H···π interactions; the first one between a cyclohexyl H atom and the furan ring (Table 1; C13-H13A···Cg1 ii . Cg1 is the centroid of the C1/C2/C7/O1/C8 furan ring), and the second one between a 3-fluorophenyl H atom and the benzene ring (Table 1; C19-H19···Cg2 iii . Cg2 is the centroid of the C2-C7 benzene ring).

Experimental
77% 3-chloroperoxybenzoic acid (515 mg, 2.3 mmol) was added in small portions to a stirred solution of 5-cyclohexyl-3-(3-fluorophenylsulfanyl)-2-methyl-1-benzofuran (374 mg, 1.1 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, 4:1 v/v) to afford the title compound as a colorless solid [yield 71%, m.p. 444-445 K; R f = 0.63 (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 positioned geometrically and refined using a riding model, with C-H = 0.95 Å for aryl, 1.00 Å for methine, 0.99Å for methylene and 0.98 Å for methyl H atoms, respectively. U iso (H) =1.2U eq (C) for aryl, methine and methylene, and 1.5U eq (C) for methyl H atoms.
supplementary materials sup-2 Figures 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.
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.