3-Cyclohexylsulfinyl-5-iodo-2-methyl-1-benzofuran

There are two independent molecules, A and B, in the asymmetric unit of the title compound, C15H17ClO2S, in each of which the cyclohexyl ring adopts a chair conformation. The benzofuran units in each molecule are essentially planar, with mean deviations from a least-squares plane defined by the nine constituent ring atoms of 0.006 (2) Å for A and 0.011 (2) Å for B. In the crystal, molecules are linked by weak intermolecular C—H⋯O and C—H⋯π interactions and by two I⋯O contacts [I⋯O = 3.079 (2) and 3.017 (2) Å].

& B] in which the benzofuran unit is essentially planar, with a mean deviation of 0.006 (2) Å for A and 0.011 (2) Å for B, respectively, from the least-squares plane defined by the nine constituent atoms. The cyclohexyl rings of both molecules adopt a chair conformation [endocyclic torsion angles are within a 51.5-59.0 (4)° range for A and 54.0-58.3 (4)° range for B, respectively].
In the crystal packing (Fig. 2), the B molecules are linked by weak intermolecular C-H···O hydrogen bonds between a methyl H atom and the O atom of the S═O unit (Table 1; C24-H24A···O4 i ), and by intermolecular C-H···π interactions between a cyclohexyl H atom and the furan ring (Table 1;  Experimental 7% 3-chloroperoxybenzoic acid (224 mg, 1.0 mmol) was added in small portions to a stirred solution of 3-cyclohexylsulfanyl-5-iodo-2-methyl-1-benzofuran (335 mg, 0.9 mmol) in dichloromethane (40 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 at reduced pressure. The residue was purified by column chromatography (hexane-ethyl acetate, 2:1 v/v) to afford the title compound as a colorless solid [yield 76%, m.p. 412-413 K; R f = 0.60 (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 ethyl acetate 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, 0.99 Å 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.

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 I1