Isopropyl 2-[5-(4-hydroxyphenyl)-3-methylsulfanyl-1-benzofuran-2-yl]acetate

In the title compound, C20H20O4S, the 4-hydroxyphenyl ring is rotated out of the plane of the benzofuran unit by 32.87 (8)°. The S—Cmethyl bond is almost perpendicular to the plane of the benzofuran fragment [77.8 (1)°] and is slightly tilted towards it. The crystal structure is stabilized by intermolecular O—H⋯O and C—H⋯O hydrogen bonds.

In the title compound, C 20 H 20 O 4 S, the 4-hydroxyphenyl ring is rotated out of the plane of the benzofuran unit by 32.87 (8) . The S-C methyl bond is almost perpendicular to the plane of the benzofuran fragment [77.8 (1) ] and is slightly tilted towards it. The crystal structure is stabilized by intermolecular O-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5043).
The benzofuran unit is essentially planar, with a mean deviation of 0.007 (2) Å from the least-squares plane defined by the nine constituent atoms. The 4-hydroxyphenyl ring is rotated out of the benzofuran plane, with a dihedral angle of 32.87 (8)°. The crystal packing (Fig. 2) is stabilized by intermolecular O-H···O and C-H···O hydrogen bonds; the first between the H atom of the hydroxy group and the oxygen of the C═O unit, with a O4-H4···O3 i , the second between the methyl H atom of the methylsulfinyl substituent and the H atom of the hydroxy group, with a C13-H13B···O4 ii , respectively (Table 1).
Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in benzene at room temperature.

Refinement
The hydroxyl H atom was found in a difference Fourier map and refined freely. The other H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 Å for the aryl, 0.97 Å for the methine and methylene, and 0.96 Å for the methyl H atoms. U iso (H) = 1.2U eq (C) for the aryl, methine and methylene 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 cycles 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.