1-(4-Bromophenylsulfonyl)-2-methylnaphtho[2,1-b]furan

In the title compound, C19H13BrO3S, the 4-bromophenyl ring makes a dihedral angle of 64.11 (2)° with the mean plane [r.m.s. deviation = 0.01 (2) Å] of the naphthofuran ring. In the crystal, molecules are linked by weak C—H⋯O and C—H⋯π interactions. The crystal structure also exhibits slipped π–π interactions between the central naphthofuran benzene rings of neighbouring molecules [centroid–centroid distance = 3.559 (2), slippage = 1.036 (2) Å], and between the central naphthofuran benzene ring and the furan ring of neighbouring molecules [centroid–centroid distance = 3.655 (2), slippage = 1.136 (2) Å].


Related literature
For background information and the crystal structures of related compounds, see: Choi et al. (2008Choi et al. ( , 2012 Table 1 Hydrogen-bond geometry (Å , ).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FF2074). As a part of our ongoing study of 2-methylnaphtho[2,1-b]furan derivatives containing 1-phenylsulfonyl (Choi et al., 2008) and 1-(4-methylphenylsulfonyl) (Choi et al., 2012) substituents, we report herein the crystal structure of the title compound.
In the title molecule ( Fig. 1), the naphthofuran unit is essentially planar, with a mean deviation of 0.017 (2) Å from the least-squares plane defined by the thirteen constituent atoms. The dihedral angle between the 4-bromophenyl ring and the mean plane of the naphthofuran ring is 64.11 (2)°. In the crystal structure ( Fig. 2), molecules are connected by weak intermolecular C-H···O and C-H···π interactions (Table 1, Cg1 is the centroid of the C14-C19 4-bromophenyl ring). In the crystal structure (Fig. 3), molecules are connected π-π interactions; the first one between the central naphthofuran benzene rings of neighbouring molecules, with a Cg2···Cg2 ii distance of 3.559 (2) Å and an interplanar distance of 3.405 (2) Å resulting in a slippage of 1.036 (2) Å (Cg2 is the centroid of the C2/C3/C8/C9/C10/C11 benzene ring), and the second one between the central naphthofuran benzene ring and the furan ring of neighbouring molecules, with a Cg2···Cg3 i distance of 3.655 (2) Å and an interplanar distance of 3.474 (2) Å resulting in a slippage of 1.136 (2) Å (Cg3 is the centroid of the C1/C2/C11/O1/C12 furan ring).

Experimental
3-Chloroperoxybenzoic acid (77%, 448 mg, 2.0 mmol) was added in small portions to a stirred solution of 1-(4-bromophenylsulfanyl)-2-methylnaphtho [2,1-b]furan (332 mg, 0.9 mmol) in dichloromethane (40 mL) at 273 K. After being stirred at room temperature for 8h, 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 (benzene) to afford the title compound as a colorless solid [yield 71%, m.p. 452-453 K; R f = 0.69 (benzene)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound in acetone at room temperature.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.95 Å for aryl and 0.98 Å for methyl H atoms. Uiso(H) = 1.2U eq (C) for aryl and 1.5U eq (C) for methyl H atoms. The positions of methyl hydrogens were optimized rotationally.   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.