2-(4-Bromophenyl)-1-(phenylsulfinyl)naphtho[2,1-b]furan

In the title compound, C24H15BrO2S, the sulfinyl O atom and the phenyl group of the phenylsulfinyl substituent lie on opposite sides of the plane through the naphthofuran fragment. The phenyl ring is nearly perpendicular to the plane of the tricyclic naphthofuran system [81.77 (6)°] and is tilted slightly towards it. The 4-bromophenyl ring is rotated out of the naphthofuran plane by a dihedral angle of 31.12 (4)°. In the crystal structure, non-classical intermolecular C—H⋯O and C—H⋯Br hydrogen bonds are observed. The crystal structure also exhibits aromatic π–π interactions between the furan ring and the central benzene ring of the adjacent naphthofuran system [centroid–centroid distance = 3.768 (3) Å]. In addition, intermolecular C—Br⋯π interactions [3.866 (2) Å] between the Br atom and the phenyl ring of the phenylsulfinyl substituent are present.

In the title compound, C 24 H 15 BrO 2 S, the sulfinyl O atom and the phenyl group of the phenylsulfinyl substituent lie on opposite sides of the plane through the naphthofuran fragment. The phenyl ring is nearly perpendicular to the plane of the tricyclic naphthofuran system [81.77 (6) ] and is tilted slightly towards it. The 4-bromophenyl ring is rotated out of the naphthofuran plane by a dihedral angle of 31.12 (4) . In the crystal structure, non-classical intermolecular C-HÁ Á ÁO and C-HÁ Á ÁBr hydrogen bonds are observed. The crystal structure also exhibits aromaticinteractions between the furan ring and the central benzene ring of the adjacent naphthofuran system [centroid-centroid distance = 3.768 (3) Å ]. In addition, intermolecular C-BrÁ Á Á interactions [3.866 (2) Å ] between the Br atom and the phenyl ring of the phenylsulfinyl substituent are present.
The naphthofuran unit is essentially planar, with a mean deviation of 0.020 (2) Å from the least-squares plane defined by the thirteen constituent atoms. The dihedral angle in (I) formed by the plane of the naphthofuran system and the plane of the 4-bromophenyl ring measures to 31.12 (4) Å. The respective dihedral angle with the phenyl ring (C19-C24) shows a value of 81.77 (6) Å with respect to the naphthofuran plane. The crystal packing (Fig. 2) is realized by non-classical intermolecular C-H···O and C-H···Br hydrogen bonds (Table 1). In the crystal structure ( Fig. 3) additionally aromatic π-π interactions between the furan ring and the central benzene ring of adjacent molecules are observed. The Cg1···Cg2 iv distance is 3.768 (3) Å (Cg1 and Cg2 are the centroides of the C1/C2/C11/O1/C12 furan and the C2/C3/C8/C9/C10/C11 benzene rings, respectively). The molecular packing (Fig. 3) also exhibits intermolecular C-Br···π interactions between the Br atom and the phenyl ring of the phenylsulfinyl substituent, with a C16-Br···Cg3 v (3.866 (2) Å ; Cg3 is the centroid of C19-C24 benzene ring).
Experimental 3-Chloroperoxybenzoic acid (77%, 157 mg, 0.7 mmol) was added in small portions to a stirred solution of 2-(4-bromophenyl)-1-(phenylsulfanyl)naphtho[2,1-b]furan (313 mg, 0.7 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 in vacuum. The residue was purified by column chromatography (hexane-ethyl acetate, 2:1 v/v) to afford the title compound as a colorless solid (yield 78%, m.p. 447-448 K; R f = 0.61 (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 = 0.93 Å and with U iso (H) = 1.2U eq (C) for aromatic 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.