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ISSN: 2056-9890

Crystal structure of 3-(2-bromo­phenyl­sulfon­yl)-2,5,7-tri­methyl-1-benzo­furan

aDepartment of Chemistry, Dongeui University, San 24 Kaya-dong, Busanjin-gu, Busan 614-714, Republic of Korea, and bDepartment of Chemistry, Pukyong National University, 599-1 Daeyeon 3-dong, Nam-gu, Busan 608-737, Republic of Korea
*Correspondence e-mail: uklee@pknu.ac.kr

Edited by J. T. Mague, Tulane University, USA (Received 29 September 2014; accepted 3 October 2014; online 8 October 2014)

In the title compound, C17H15BrO3S, the dihedral angle between the planes of the benzo­furan ring system [r.m.s. deviation = 0.016 (2) Å] and the 2-bromo­phenyl ring is 82.93 (6)°. In the crystal, mol­ecules are linked via pairs of C—H⋯π hydrogen bonds and ππ inter­actions between the benzene and furan rings of neighbouring mol­ecules [centroid–centroid distance = 3.881 (2) Å] into inversion-related dimers along the b-axis direction. These dimers are further linked by short Br⋯O [3.185 (2) Å] contacts.

1. Related literature

For a related structure and background to benzo­furan derivatives, see: Choi & Lee (2014[Choi, H. D. & Lee, U. (2014). Acta Cryst. E70, o1073-o1074.]). For further synthetic details, see: Choi et al. (1999[Choi, H. D., Seo, P. J. & Son, B. W. (1999). J. Korean Chem. Soc. 43, 606-608.]). For a review of halogen bonding, see: Politzer et al. (2007[Politzer, P., Lane, P., Concha, M. C., Ma, Y. & Murray, J. S. (2007). J. Mol. Model. 13, 305-311.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C17H15BrO3S

  • Mr = 379.26

  • Monoclinic, P 21 /n

  • a = 7.8969 (2) Å

  • b = 8.1489 (2) Å

  • c = 24.3146 (6) Å

  • β = 96.210 (1)°

  • V = 1555.49 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.79 mm−1

  • T = 173 K

  • 0.31 × 0.27 × 0.13 mm

2.2. Data collection

  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.479, Tmax = 0.713

  • 27395 measured reflections

  • 3867 independent reflections

  • 3130 reflections with I > 2σ(I)

  • Rint = 0.042

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.080

  • S = 1.03

  • 3867 reflections

  • 202 parameters

  • H-atom parameters constrained

  • Δρmax = 0.51 e Å−3

  • Δρmin = −0.34 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C2–C7 benzene ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9CCg1i 0.98 2.84 3.608 (2) 136
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg, 1998[Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

As a part of our continuing program for benzofuran derivatives (Choi & Lee, 2014), we report herein on the crystal structure of the title compound.

In the title molecule (Fig. 1), the benzofuran unit is essentially planar, with a mean deviation of 0.016 (2) Å from the least-squares plane defined by the nine constituent atoms. The 2-bromophenyl ring is essentially planar, with a mean deviation of 0.004 (2) Å from the least-squares plane defined by the six constituent atoms. The dihedral angle formed by the benzofuran ring and the 2-bromophenyl ring is 82.93 (6)°. In the crystal structure (Fig. 2), molecules are linked via two different pairs of C—H···π hydrogen bonds (Table 1, Cg1 is the centroid of the C2–C7 benzene ring) and ππ interactions between the benzene and furan rings of neighbouring molecules, with a Cg1···Cg2iii distance of 3.881 (2) Å and an interplanar distance of 3.562 (2) Å resulting in a slippage of 1.541 (2) Å (Cg2 is the centroid of the C1/C2/C7/O1/C8 furan ring), into inversion-related dimers along the b-axis direction. These dimers are further linked by halogen-bondings (Politzer et al. 2007) between the bromine and the O atom of the OSO unit [Br1..O3ii = 3.185 (2) Å, C17—Br1···O3ii = 164.49 (7)°, symmetry code: (ii) - x + 1/2, y - 1/2, - z + 3/2].

Related literature top

For a related structure and background to benzofuran derivatives, see: Choi & Lee (2014). For further synthetic details, see: Choi et al. (1999). For a review of halogen bonding, see: Politzer et al. (2007).

Experimental top

The starting material 3-(2-bromophenylsulfanyl)-2,5,7-trimethyl-1-benzofuran was prepared by a literature method (Choi et al., 1999). 3-Chloroperoxybenzoic acid (77%, 403 mg, 1.8 mmol) was added in small portions to a stirred solution of 3-(2-bromophenylsulfanyl)-2,5,7-trimethyl-1-benzofuran (278 mg, 0.8 mmol) in dichloromethane (30 ml) at 273 K. After being stirred at room temperature for 8h, the mixture was washed with saturated sodium bicarbonate solution (2 X 10 ml) 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 72% (218 mg); m.p. 453–454 K; Rf = 0.51 (hexane-ethyl acetate, 4:1 v/v)]. Single crystals suitable for X-ray diffraction were prepared by slow evaporation of a solution of the title compound (21 mg) in acetone (15 ml) at room temperature.

Refinement top

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, respectively. Uiso (H) = 1.2Ueq (C) for aryl and 1.5Ueq (C)) for methyl H atoms. The positions of methyl hydrogens were optimized using the SHELXL-97's command AFIX 137 (Sheldrick, 2008).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
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 small spheres of arbitrary radius.

Fig. 2. A view of the C—H···π, ππ and Br···O interactions (dotted lines) in the crystal structure of the title compound. H atoms non-participating in hydrogen-bonding were omitted for clarity. [Symmetry codes: (i) - x + 1, - y + 1, - z + 1; (ii) - x + 1/2, y - 1/2, - z + 3/2 ; (iii) - x, - y + 1, - z + 1; (iv) - x + 1/2, y + 1/2, - z + 3/2.]
3-(2-Bromophenylsulfonyl)-2,5,7-trimethyl-1-benzofuran top
Crystal data top
C17H15BrO3SF(000) = 768
Mr = 379.26Dx = 1.619 Mg m3
Monoclinic, P21/nMelting point = 454–453 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 7.8969 (2) ÅCell parameters from 7387 reflections
b = 8.1489 (2) Åθ = 2.6–26.1°
c = 24.3146 (6) ŵ = 2.79 mm1
β = 96.210 (1)°T = 173 K
V = 1555.49 (7) Å3Block, colourless
Z = 40.31 × 0.27 × 0.13 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
3867 independent reflections
Radiation source: rotating anode3130 reflections with I > 2σ(I)
Graphite multilayer monochromatorRint = 0.042
Detector resolution: 10.0 pixels mm-1θmax = 28.3°, θmin = 1.7°
ϕ and ω scansh = 1010
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
k = 1010
Tmin = 0.479, Tmax = 0.713l = 3132
27395 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.031Hydrogen site location: difference Fourier map
wR(F2) = 0.080H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0401P)2 + 0.8758P]
where P = (Fo2 + 2Fc2)/3
3867 reflections(Δ/σ)max = 0.001
202 parametersΔρmax = 0.51 e Å3
0 restraintsΔρmin = 0.34 e Å3
Crystal data top
C17H15BrO3SV = 1555.49 (7) Å3
Mr = 379.26Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.8969 (2) ŵ = 2.79 mm1
b = 8.1489 (2) ÅT = 173 K
c = 24.3146 (6) Å0.31 × 0.27 × 0.13 mm
β = 96.210 (1)°
Data collection top
Bruker SMART APEXII CCD
diffractometer
3867 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3130 reflections with I > 2σ(I)
Tmin = 0.479, Tmax = 0.713Rint = 0.042
27395 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0310 restraints
wR(F2) = 0.080H-atom parameters constrained
S = 1.03Δρmax = 0.51 e Å3
3867 reflectionsΔρmin = 0.34 e Å3
202 parameters
Special details top

Experimental. 1H NMR (δ p.p.m., CDCl3, 400 Hz): 8.49 (d, J = 6.12 Hz, 1H), 7.65 (d, J =6.84 Hz, 1H), 7.53-7.58 (m, 1H), 7.38-7.43 (m, 1H), 7.06 (s, 1H), 6.88 (s, 1H), 2.84 (s, 3H), 2.43 (s, 3H), 2.31 (s, 3H).

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 F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 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 (Å2) top
xyzUiso*/Ueq
Br10.46256 (3)0.42412 (3)0.713662 (9)0.03093 (9)
S10.12638 (7)0.65915 (7)0.65837 (2)0.02299 (13)
O10.1202 (2)0.22941 (18)0.58642 (6)0.0280 (4)
O20.0262 (2)0.7852 (2)0.62933 (7)0.0320 (4)
O30.0830 (2)0.6094 (2)0.71169 (7)0.0311 (4)
C10.1294 (3)0.4896 (3)0.61574 (9)0.0222 (4)
C20.1822 (3)0.4890 (3)0.56071 (8)0.0208 (4)
C30.2360 (3)0.6058 (3)0.52431 (9)0.0241 (4)
H30.24020.71900.53370.029*
C40.2832 (3)0.5521 (3)0.47408 (9)0.0257 (5)
C50.2767 (3)0.3855 (3)0.46099 (9)0.0273 (5)
H50.31060.35210.42640.033*
C60.2235 (3)0.2660 (3)0.49579 (9)0.0270 (5)
C70.1761 (3)0.3251 (3)0.54484 (9)0.0229 (4)
C80.0946 (3)0.3321 (3)0.62932 (9)0.0258 (5)
C90.3440 (3)0.6725 (3)0.43345 (10)0.0350 (6)
H9A0.26620.76640.42940.053*
H9B0.34670.61880.39750.053*
H9C0.45870.71050.44700.053*
C100.2218 (4)0.0869 (3)0.48191 (12)0.0412 (6)
H10A0.24640.02280.51590.062*
H10B0.30840.06420.45700.062*
H10C0.10930.05660.46380.062*
C110.0392 (3)0.2511 (3)0.67846 (10)0.0378 (6)
H11A0.13170.18210.69580.057*
H11B0.06080.18270.66740.057*
H11C0.00990.33440.70490.057*
C120.3401 (3)0.7318 (3)0.66497 (8)0.0220 (4)
C130.3630 (3)0.8918 (3)0.64809 (10)0.0286 (5)
H130.26780.95430.63270.034*
C140.5241 (3)0.9611 (3)0.65352 (11)0.0365 (6)
H140.53901.07140.64230.044*
C150.6626 (3)0.8704 (3)0.67508 (11)0.0363 (6)
H150.77300.91810.67850.044*
C160.6417 (3)0.7101 (3)0.69174 (10)0.0315 (5)
H160.73770.64760.70630.038*
C170.4809 (3)0.6409 (3)0.68725 (9)0.0238 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.03549 (14)0.02720 (13)0.02903 (14)0.00525 (10)0.00148 (9)0.00300 (9)
S10.0223 (3)0.0245 (3)0.0227 (3)0.0008 (2)0.0050 (2)0.0029 (2)
O10.0390 (9)0.0201 (7)0.0247 (8)0.0047 (7)0.0030 (7)0.0020 (6)
O20.0277 (8)0.0306 (9)0.0366 (9)0.0082 (7)0.0009 (7)0.0044 (7)
O30.0319 (8)0.0388 (10)0.0243 (8)0.0031 (7)0.0113 (7)0.0042 (7)
C10.0231 (10)0.0228 (10)0.0209 (11)0.0007 (8)0.0030 (8)0.0005 (8)
C20.0197 (10)0.0225 (10)0.0201 (10)0.0011 (8)0.0018 (8)0.0005 (8)
C30.0275 (11)0.0204 (10)0.0244 (11)0.0008 (8)0.0033 (9)0.0006 (8)
C40.0248 (11)0.0295 (11)0.0229 (11)0.0006 (9)0.0031 (9)0.0018 (9)
C50.0304 (11)0.0307 (12)0.0214 (11)0.0033 (9)0.0052 (9)0.0048 (9)
C60.0299 (11)0.0255 (11)0.0248 (12)0.0019 (9)0.0001 (9)0.0043 (9)
C70.0258 (11)0.0208 (10)0.0217 (11)0.0016 (8)0.0012 (8)0.0016 (8)
C80.0282 (11)0.0258 (11)0.0236 (11)0.0030 (9)0.0031 (9)0.0012 (9)
C90.0391 (14)0.0392 (14)0.0283 (13)0.0014 (11)0.0106 (11)0.0039 (11)
C100.0618 (18)0.0252 (12)0.0368 (15)0.0020 (12)0.0065 (13)0.0082 (11)
C110.0508 (16)0.0351 (13)0.0288 (13)0.0102 (12)0.0098 (11)0.0050 (11)
C120.0242 (10)0.0244 (11)0.0180 (10)0.0011 (8)0.0055 (8)0.0046 (8)
C130.0346 (12)0.0241 (11)0.0278 (12)0.0005 (9)0.0057 (10)0.0006 (9)
C140.0477 (15)0.0286 (12)0.0349 (14)0.0092 (11)0.0124 (12)0.0037 (10)
C150.0308 (12)0.0455 (15)0.0339 (14)0.0116 (11)0.0085 (11)0.0094 (12)
C160.0256 (11)0.0428 (14)0.0261 (12)0.0003 (10)0.0034 (9)0.0053 (10)
C170.0293 (11)0.0262 (11)0.0163 (10)0.0023 (9)0.0044 (8)0.0027 (8)
Geometric parameters (Å, º) top
Br1—C171.890 (2)C8—C111.472 (3)
Br1—O3i22.6093 (17)C9—H9A0.9800
S1—O31.4345 (16)C9—H9B0.9800
S1—O21.4348 (17)C9—H9C0.9800
S1—C11.729 (2)C10—H10A0.9800
S1—C121.779 (2)C10—H10B0.9800
O1—C81.369 (3)C10—H10C0.9800
O1—C71.386 (3)C11—H11A0.9800
C1—C81.361 (3)C11—H11B0.9800
C1—C21.444 (3)C11—H11C0.9800
C2—C71.390 (3)C12—C131.385 (3)
C2—C31.397 (3)C12—C171.396 (3)
C3—C41.386 (3)C13—C141.385 (4)
C3—H30.9500C13—H130.9500
C4—C51.395 (3)C14—C151.376 (4)
C4—C91.507 (3)C14—H140.9500
C5—C61.385 (3)C15—C161.383 (4)
C5—H50.9500C15—H150.9500
C6—C71.375 (3)C16—C171.383 (3)
C6—C101.497 (3)C16—H160.9500
C17—Br1—O3i76.20 (6)H9A—C9—H9B109.5
O3—S1—O2118.32 (10)C4—C9—H9C109.5
O3—S1—C1109.64 (10)H9A—C9—H9C109.5
O2—S1—C1108.65 (10)H9B—C9—H9C109.5
O3—S1—C12109.22 (10)C6—C10—H10A109.5
O2—S1—C12105.85 (10)C6—C10—H10B109.5
C1—S1—C12104.19 (10)H10A—C10—H10B109.5
C8—O1—C7107.27 (16)C6—C10—H10C109.5
C8—C1—C2107.93 (19)H10A—C10—H10C109.5
C8—C1—S1126.30 (17)H10B—C10—H10C109.5
C2—C1—S1125.62 (16)C8—C11—H11A109.5
C7—C2—C3118.87 (19)C8—C11—H11B109.5
C7—C2—C1104.80 (18)H11A—C11—H11B109.5
C3—C2—C1136.3 (2)C8—C11—H11C109.5
C4—C3—C2118.2 (2)H11A—C11—H11C109.5
C4—C3—H3120.9H11B—C11—H11C109.5
C2—C3—H3120.9C13—C12—C17119.4 (2)
C3—C4—C5120.1 (2)C13—C12—S1116.07 (17)
C3—C4—C9120.5 (2)C17—C12—S1124.50 (17)
C5—C4—C9119.4 (2)C12—C13—C14120.3 (2)
C6—C5—C4123.5 (2)C12—C13—H13119.9
C6—C5—H5118.3C14—C13—H13119.9
C4—C5—H5118.3C15—C14—C13120.1 (2)
C7—C6—C5114.4 (2)C15—C14—H14120.0
C7—C6—C10122.7 (2)C13—C14—H14120.0
C5—C6—C10122.9 (2)C14—C15—C16120.3 (2)
C6—C7—O1125.00 (19)C14—C15—H15119.9
C6—C7—C2124.9 (2)C16—C15—H15119.9
O1—C7—C2110.03 (18)C17—C16—C15120.0 (2)
C1—C8—O1109.95 (18)C17—C16—H16120.0
C1—C8—C11134.9 (2)C15—C16—H16120.0
O1—C8—C11115.2 (2)C16—C17—C12120.0 (2)
C4—C9—H9A109.5C16—C17—Br1117.25 (18)
C4—C9—H9B109.5C12—C17—Br1122.73 (17)
O3—S1—C1—C80.8 (2)C1—C2—C7—O11.1 (2)
O2—S1—C1—C8129.9 (2)C2—C1—C8—O10.4 (2)
C12—S1—C1—C8117.6 (2)S1—C1—C8—O1176.16 (16)
O3—S1—C1—C2174.23 (18)C2—C1—C8—C11178.8 (3)
O2—S1—C1—C255.1 (2)S1—C1—C8—C113.0 (4)
C12—S1—C1—C257.4 (2)C7—O1—C8—C11.1 (2)
C8—C1—C2—C70.4 (2)C7—O1—C8—C11178.3 (2)
S1—C1—C2—C7175.34 (16)O3—S1—C12—C13121.32 (17)
C8—C1—C2—C3178.9 (2)O2—S1—C12—C137.10 (19)
S1—C1—C2—C33.1 (4)C1—S1—C12—C13121.60 (18)
C7—C2—C3—C40.8 (3)O3—S1—C12—C1756.5 (2)
C1—C2—C3—C4177.4 (2)O2—S1—C12—C17175.07 (17)
C2—C3—C4—C50.1 (3)C1—S1—C12—C1760.6 (2)
C2—C3—C4—C9179.4 (2)C17—C12—C13—C140.3 (3)
C3—C4—C5—C60.4 (4)S1—C12—C13—C14177.65 (18)
C9—C4—C5—C6179.7 (2)C12—C13—C14—C150.8 (4)
C4—C5—C6—C70.3 (3)C13—C14—C15—C160.4 (4)
C4—C5—C6—C10178.2 (2)C14—C15—C16—C170.6 (4)
C5—C6—C7—O1179.3 (2)C15—C16—C17—C121.2 (3)
C10—C6—C7—O10.8 (4)C15—C16—C17—Br1177.56 (18)
C5—C6—C7—C21.4 (3)C13—C12—C17—C160.7 (3)
C10—C6—C7—C2177.2 (2)S1—C12—C17—C16178.47 (17)
C8—O1—C7—C6176.8 (2)C13—C12—C17—Br1177.95 (16)
C8—O1—C7—C21.4 (2)S1—C12—C17—Br10.2 (3)
C3—C2—C7—C61.7 (3)O3i—Br1—C17—C1699.99 (17)
C1—C2—C7—C6177.1 (2)O3i—Br1—C17—C1281.32 (17)
C3—C2—C7—O1179.89 (18)
Symmetry code: (i) x+1/2, y1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C2–C7 benzene ring.
D—H···AD—HH···AD···AD—H···A
C9—H9C···Cg1ii0.982.843.608 (2)136
Symmetry code: (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C2–C7 benzene ring.
D—H···AD—HH···AD···AD—H···A
C9—H9C···Cg1i0.982.843.608 (2)136.3
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

The X-ray centre of Gyeongsang National University is acknowledged for providing access to the single-crystal diffractometer.

References

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