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Acta Crystallogr Sect E Struct Rep Online. 2009 February 1; 65(Pt 2): o265.
Published online 2009 January 8. doi:  10.1107/S1600536808043985
PMCID: PMC2968244

Butyl 2-(5-bromo-3-methyl­sulfinyl-1-benzofuran-2-yl)acetate

Abstract

In the title compound, C15H17BrO4S, the methyl­sulfinyl O atom and the methyl substituents lie on opposite sides of the plane through the benzofuran fragment. The crystal structure is stabilized by π–π inter­actions between the benzene rings of neighbouring mol­ecules [centroid–centroid distance = 3.698 (4) Å], and by C—H(...)π inter­actions between a methyl­ene H atom of the butyl group and the benzene ring of the benzofuran system. Additionally, the crystal structure exhibits weak inter­molecular C—H(...)O contacts. The butyl group is disordered over two positions, with site-occupancy factors, from refinement, of 0.720 (8) and 0.280 (8).

Related literature

For the crystal structures of similar alkyl 2-(5-bromo-3-methyl­sulfinyl-1-benzofuran-2-yl)acetate derivatives. see: Choi et al. (2008a [triangle],b [triangle]).

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Object name is e-65-0o265-scheme1.jpg

Experimental

Crystal data

  • C15H17BrO4S
  • M r = 373.26
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0o265-efi1.jpg
  • a = 8.420 (1) Å
  • b = 10.255 (1) Å
  • c = 10.306 (1) Å
  • α = 97.503 (2)°
  • β = 99.711 (2)°
  • γ = 108.678 (2)°
  • V = 814.55 (15) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 2.66 mm−1
  • T = 298 (2) K
  • 0.40 × 0.40 × 0.30 mm

Data collection

  • Bruker SMART CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1999 [triangle]) T min = 0.353, T max = 0.451
  • 6560 measured reflections
  • 3179 independent reflections
  • 2645 reflections with I > 2σ(I)
  • R int = 0.017

Refinement

  • R[F 2 > 2σ(F 2)] = 0.033
  • wR(F 2) = 0.089
  • S = 1.14
  • 3179 reflections
  • 229 parameters
  • 64 restraints
  • H-atom parameters constrained
  • Δρmax = 0.30 e Å−3
  • Δρmin = −0.50 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg, 1998 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808043985/tk2347sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808043985/tk2347Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

This work is related to our previous communications on the synthesis and structure of alkyl 2-(5-bromo-3-methylsulfinyl-1-benzofuran-2-yl)acetate analogues, viz. isopropyl 2-(5-bromo-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008a) and methyl 2-(5-bromo-3-methylsulfinyl-1-benzofuran-2-yl)acetate (Choi et al., 2008b). Herein, we describe the crystal structure of the title compound, (I).

The benzofuran unit is essentially planar, with a mean deviation of 0.012 (2) Å from the least-squares plane defined by the nine constituent atoms. The butyl group is disordered over two positions with site-occupancy factors of 0.720 (8) (for atoms labelled B) and 0.280 (8) (B) in Fig. 1. The molecular packing is stabilized by intermolecular π—π interactions: the Cg···Cgii distance is 3.698 (4) Å, where Cg is the centroid of the C2–C7 ring, symmetry code as in Fig. 2. The molecular packing is further stabilized by C—H···π interactions between the methylene-H and the benzene ring of the benzofuran system, with a C12A—H12A···Cgi separation of 2.78 Å, Table 1; Cg is the centroid of the C2–C7 benzene ring. In addition, weak intermolecular C—H···O contacts are observed, Table 1. One C-H···O contact occurs between a benzene-H and the O3-oxygen, and a second between a methylene-H and the O4-oxygen atom.

Experimental

77% 3-Chloroperoxybenzoic acid (148 mg, 0.66 mmol) was added in small portions to a stirred solution of butyl 2-(5-bromo-3-methylsulfanyl-1-benzofuran-2-yl)acetate (214 mg, 0.6 mmol) in dichloromethane (30 ml) at 273 K. After being stirred for 3 h at room temperature, the mixture was washed with saturated sodium bicarbonate solution and the organic layer separated, dried over magnesium sulfate, filtered and concentrated in vacuum. The residue was purified by column chromatography (hexane-ethyl acetate, 1:2 v/v) to afford (I) as a colorless solid [yield 80%, m.p. 381–382 K; Rf = 0.65 (hexane-ethyl acetate, 1;2 v/v)]. Single crystals were obtained by evaporation of an acetone solution of (I). Spectroscopic analysis: 1H NMR (CDCl3, 400 MHz) δ 0.92 (t, J = 7.32 Hz, 3H), 1.31–1.41 (m, 2H), 1.59–1.67 (m, 2H), 3.07 (s, 3H), 4.04 (s, 2H), 4.15 (t, J = 6.6 Hz, 2H), 7.39 (d, J = 8.8 Hz, 1H), 7.49 (dd, J = 8.8 Hz and J = 2.2 Hz, 1H), 8.11 (d, J = 1.84 Hz, 1H); EI—MS 374 [M+2], 372 [M+].

Refinement

All H atoms were geometrically positioned and refined using a riding model, with C—H = 0.93 Å for aryl-, 0.97 Å for methylene-, and 0.96 Å for methyl-H atoms, and with Uiso(H) = 1.2Ueq(C) for the aryl- and methylene-H atoms, and 1.5Ueq(C) for methyl-H atoms. The butyl group was found to be disordered over two positions and modelled with site-occupancy factors, from refinement, of 0.720 (8) (C11A–C14A)) and 0.280 (8) (C11B–C14B). The displacement ellipsoids of part B part were restrained using command ISOR (0.01), both sets of C atoms were restrained using the command DELU, and the C—C distances were restrained to 1.480 (2) Å using command DFIX.

Figures

Fig. 1.
The molecular structure of (I), showing displacement ellipsoids drawn at the 30% probability level. The butyl group is disordered over two positions with the major component having a site occupancy = 0.720 (8).
Fig. 2.
Diagram illustrating the π—π, C—H···π and C—H···O interactions (dotted lines) in the crystal structure of (I). Cg denotes a ring centroid. The disordered component ...

Crystal data

C15H17BrO4SZ = 2
Mr = 373.26F(000) = 380
Triclinic, P1Dx = 1.522 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.420 (1) ÅCell parameters from 3446 reflections
b = 10.255 (1) Åθ = 2.6–27.0°
c = 10.306 (1) ŵ = 2.66 mm1
α = 97.503 (2)°T = 298 K
β = 99.711 (2)°Block, colorless
γ = 108.678 (2)°0.40 × 0.40 × 0.30 mm
V = 814.55 (15) Å3

Data collection

Bruker SMART CCD diffractometer3179 independent reflections
Radiation source: fine-focus sealed tube2645 reflections with I > 2σ(I)
graphiteRint = 0.017
Detector resolution: 10.0 pixels mm-1θmax = 26.0°, θmin = 2.1°
[var phi] and ω scansh = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 1999)k = −12→12
Tmin = 0.353, Tmax = 0.451l = −12→12
6560 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: difference Fourier map
wR(F2) = 0.089H-atom parameters constrained
S = 1.14w = 1/[σ2(Fo2) + (0.0442P)2 + 0.2004P] where P = (Fo2 + 2Fc2)/3
3179 reflections(Δ/σ)max < 0.001
229 parametersΔρmax = 0.30 e Å3
64 restraintsΔρmin = −0.50 e Å3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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)

xyzUiso*/UeqOcc. (<1)
Br−0.42599 (4)0.24082 (3)0.12584 (3)0.06775 (14)
S0.32177 (9)0.58854 (7)0.45871 (6)0.04988 (17)
O10.3033 (2)0.46045 (17)0.07725 (15)0.0442 (4)
O20.7594 (3)0.8276 (2)0.2120 (2)0.0686 (6)
O30.5174 (3)0.8291 (2)0.2711 (2)0.0721 (6)
O40.2197 (3)0.4784 (2)0.52321 (18)0.0618 (5)
C10.2665 (3)0.5195 (2)0.2849 (2)0.0413 (5)
C20.0997 (3)0.4347 (2)0.2012 (2)0.0401 (5)
C3−0.0682 (3)0.3882 (3)0.2186 (2)0.0447 (5)
H3−0.09410.41080.30100.054*
C4−0.1944 (3)0.3070 (3)0.1078 (3)0.0472 (6)
C5−0.1604 (4)0.2716 (3)−0.0175 (3)0.0509 (6)
H5−0.25000.2159−0.08890.061*
C60.0052 (3)0.3188 (3)−0.0354 (2)0.0478 (6)
H60.03070.2966−0.11810.057*
C70.1318 (3)0.4008 (2)0.0749 (2)0.0414 (5)
C80.3827 (3)0.5320 (2)0.2067 (2)0.0417 (5)
C90.5701 (3)0.6117 (3)0.2310 (3)0.0460 (6)
H9A0.61500.57670.15860.055*
H9B0.62810.59590.31400.055*
C100.6090 (3)0.7675 (3)0.2403 (3)0.0506 (6)
C11A0.8140 (8)0.9810 (14)0.2252 (11)0.087 (3)0.720 (8)
H11A0.81171.02450.31390.104*0.720 (8)
H11B0.73751.00530.15900.104*0.720 (8)
C12A0.9913 (6)1.0302 (6)0.2033 (6)0.0749 (16)0.720 (8)
H12A1.02071.12320.18210.090*0.720 (8)
H12B1.00360.96640.13070.090*0.720 (8)
C13A1.1021 (6)1.0324 (8)0.3331 (7)0.098 (2)0.720 (8)
H13A1.07121.08330.40500.117*0.720 (8)
H13B1.07660.93660.34640.117*0.720 (8)
C14A1.2899 (7)1.0964 (9)0.3450 (10)0.134 (3)0.720 (8)
H14A1.34991.09670.43300.202*0.720 (8)
H14B1.31731.19110.33090.202*0.720 (8)
H14C1.32431.04290.27880.202*0.720 (8)
C11B0.806 (2)0.973 (3)0.183 (2)0.070 (5)0.280 (8)
H11C0.72311.01530.20250.084*0.280 (8)
H11D0.81380.97210.09030.084*0.280 (8)
C12B0.9768 (19)1.049 (2)0.275 (3)0.127 (7)0.280 (8)
H12C0.96141.03610.36450.153*0.280 (8)
H12D1.00031.14750.27460.153*0.280 (8)
C13B1.1377 (19)1.0231 (18)0.2628 (16)0.087 (5)0.280 (8)
H13C1.13200.92700.26220.105*0.280 (8)
H13D1.18841.06010.19150.105*0.280 (8)
C14B1.207 (3)1.117 (2)0.3964 (16)0.124 (6)0.280 (8)
H14D1.33051.15470.41330.186*0.280 (8)
H14E1.17291.06550.46430.186*0.280 (8)
H14F1.16341.19310.39850.186*0.280 (8)
C150.2192 (5)0.7173 (3)0.4576 (3)0.0679 (8)
H15A0.09710.67100.42660.102*
H15B0.26150.77880.39870.102*
H15C0.24420.77100.54680.102*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br0.04457 (17)0.0686 (2)0.0882 (3)0.01726 (14)0.01642 (15)0.01369 (16)
S0.0507 (4)0.0625 (4)0.0376 (3)0.0229 (3)0.0092 (3)0.0067 (3)
O10.0471 (9)0.0509 (10)0.0400 (9)0.0212 (8)0.0158 (7)0.0093 (7)
O20.0515 (11)0.0466 (11)0.1135 (17)0.0178 (9)0.0256 (11)0.0246 (11)
O30.0637 (13)0.0590 (12)0.1004 (16)0.0315 (11)0.0233 (12)0.0072 (11)
O40.0721 (13)0.0801 (14)0.0466 (10)0.0348 (11)0.0218 (9)0.0265 (9)
C10.0462 (13)0.0449 (13)0.0361 (12)0.0191 (10)0.0103 (10)0.0099 (10)
C20.0474 (13)0.0399 (12)0.0393 (12)0.0203 (10)0.0129 (10)0.0123 (10)
C30.0474 (13)0.0471 (13)0.0471 (14)0.0220 (11)0.0160 (11)0.0146 (11)
C40.0448 (13)0.0421 (13)0.0588 (15)0.0192 (11)0.0119 (11)0.0135 (11)
C50.0537 (15)0.0468 (14)0.0504 (14)0.0221 (12)0.0019 (12)0.0044 (11)
C60.0561 (15)0.0515 (14)0.0400 (13)0.0261 (12)0.0099 (11)0.0061 (11)
C70.0449 (13)0.0420 (12)0.0440 (12)0.0211 (10)0.0134 (10)0.0117 (10)
C80.0462 (13)0.0441 (13)0.0399 (12)0.0209 (10)0.0111 (10)0.0112 (10)
C90.0447 (13)0.0512 (14)0.0480 (14)0.0215 (11)0.0144 (11)0.0132 (11)
C100.0463 (14)0.0517 (15)0.0531 (15)0.0191 (12)0.0068 (11)0.0085 (12)
C11A0.072 (4)0.059 (4)0.137 (7)0.029 (3)0.019 (4)0.032 (5)
C12A0.075 (3)0.044 (2)0.105 (4)0.013 (2)0.022 (3)0.028 (3)
C13A0.072 (3)0.080 (4)0.117 (5)0.002 (3)0.004 (3)0.024 (4)
C14A0.077 (4)0.120 (5)0.175 (7)−0.001 (4)0.024 (4)0.018 (5)
C11B0.072 (7)0.040 (8)0.096 (9)0.008 (5)0.016 (6)0.034 (7)
C12B0.110 (8)0.109 (10)0.162 (12)0.054 (8)−0.005 (7)0.028 (9)
C13B0.085 (7)0.086 (8)0.089 (8)0.028 (6)0.022 (6)0.012 (6)
C14B0.122 (10)0.135 (10)0.109 (9)0.053 (8)0.012 (7)0.000 (7)
C150.087 (2)0.0654 (19)0.0637 (18)0.0394 (17)0.0291 (16)0.0087 (15)

Geometric parameters (Å, °)

Br—C41.899 (3)C11A—H11A0.9700
S—O41.491 (2)C11A—H11B0.9700
S—C11.762 (2)C12A—C13A1.489 (2)
S—C151.794 (3)C12A—H12A0.9700
O1—C71.370 (3)C12A—H12B0.9700
O1—C81.376 (3)C13A—C14A1.482 (2)
O2—C101.319 (3)C13A—H13A0.9700
O2—C11A1.471 (14)C13A—H13B0.9700
O2—C11B1.50 (3)C14A—H14A0.9600
O3—C101.199 (3)C14A—H14B0.9600
C1—C81.355 (3)C14A—H14C0.9600
C1—C21.444 (3)C11B—C12B1.481 (2)
C2—C31.391 (3)C11B—H11C0.9700
C2—C71.396 (3)C11B—H11D0.9700
C3—C41.380 (4)C12B—C13B1.483 (2)
C3—H30.9300C12B—H12C0.9700
C4—C51.396 (4)C12B—H12D0.9700
C5—C61.376 (4)C13B—C14B1.481 (2)
C5—H50.9300C13B—H13C0.9700
C6—C71.380 (3)C13B—H13D0.9700
C6—H60.9300C14B—H14D0.9600
C8—C91.486 (3)C14B—H14E0.9600
C9—C101.511 (4)C14B—H14F0.9600
C9—H9A0.9700C15—H15A0.9600
C9—H9B0.9700C15—H15B0.9600
C11A—C12A1.482 (2)C15—H15C0.9600
O4—S—C1106.92 (12)C11A—C12A—H12A110.8
O4—S—C15105.78 (14)C13A—C12A—H12A110.8
C1—S—C1598.46 (13)C11A—C12A—H12B110.8
C7—O1—C8106.62 (17)C13A—C12A—H12B110.8
C10—O2—C11A115.2 (3)H12A—C12A—H12B108.9
C10—O2—C11B120.0 (10)C14A—C13A—C12A115.7 (6)
C11A—O2—C11B16.2 (11)C14A—C13A—H13A108.4
C8—C1—C2107.4 (2)C12A—C13A—H13A108.4
C8—C1—S123.77 (19)C14A—C13A—H13B108.4
C2—C1—S128.70 (18)C12A—C13A—H13B108.4
C3—C2—C7119.5 (2)H13A—C13A—H13B107.4
C3—C2—C1135.8 (2)C13A—C14A—H14A109.5
C7—C2—C1104.6 (2)C13A—C14A—H14B109.5
C4—C3—C2116.8 (2)H14A—C14A—H14B109.5
C4—C3—H3121.6C13A—C14A—H14C109.5
C2—C3—H3121.6H14A—C14A—H14C109.5
C3—C4—C5123.2 (2)H14B—C14A—H14C109.5
C3—C4—Br118.51 (19)O2—C11B—C12B104 (2)
C5—C4—Br118.29 (19)O2—C11B—H11C111.1
C6—C5—C4120.2 (2)C12B—C11B—H11C111.1
C6—C5—H5119.9O2—C11B—H11D111.1
C4—C5—H5119.9C12B—C11B—H11D111.1
C5—C6—C7116.8 (2)H11C—C11B—H11D109.0
C5—C6—H6121.6C11B—C12B—C13B125 (2)
C7—C6—H6121.6C11B—C12B—H12C106.1
O1—C7—C6125.9 (2)C13B—C12B—H12C106.1
O1—C7—C2110.7 (2)C11B—C12B—H12D106.1
C6—C7—C2123.5 (2)C13B—C12B—H12D106.1
C1—C8—O1110.7 (2)H12C—C12B—H12D106.3
C1—C8—C9133.3 (2)C14B—C13B—C12B83.6 (14)
O1—C8—C9115.9 (2)C14B—C13B—H13C114.7
C8—C9—C10112.3 (2)C12B—C13B—H13C114.7
C8—C9—H9A109.1C14B—C13B—H13D114.7
C10—C9—H9A109.1C12B—C13B—H13D114.7
C8—C9—H9B109.1H13C—C13B—H13D111.8
C10—C9—H9B109.1C13B—C14B—H14D109.5
H9A—C9—H9B107.9C13B—C14B—H14E109.5
O3—C10—O2124.3 (3)H14D—C14B—H14E109.5
O3—C10—C9124.9 (3)C13B—C14B—H14F109.5
O2—C10—C9110.8 (2)H14D—C14B—H14F109.5
O2—C11A—C12A107.2 (8)H14E—C14B—H14F109.5
O2—C11A—H11A110.3S—C15—H15A109.5
C12A—C11A—H11A110.3S—C15—H15B109.5
O2—C11A—H11B110.3H15A—C15—H15B109.5
C12A—C11A—H11B110.3S—C15—H15C109.5
H11A—C11A—H11B108.5H15A—C15—H15C109.5
C11A—C12A—C13A104.5 (6)H15B—C15—H15C109.5
O4—S—C1—C8−136.3 (2)C2—C1—C8—O1−0.3 (3)
C15—S—C1—C8114.3 (2)S—C1—C8—O1176.29 (16)
O4—S—C1—C239.5 (2)C2—C1—C8—C9175.7 (2)
C15—S—C1—C2−69.9 (2)S—C1—C8—C9−7.8 (4)
C8—C1—C2—C3−177.6 (3)C7—O1—C8—C1−0.3 (2)
S—C1—C2—C36.1 (4)C7—O1—C8—C9−177.00 (19)
C8—C1—C2—C70.7 (3)C1—C8—C9—C10−73.0 (3)
S—C1—C2—C7−175.63 (18)O1—C8—C9—C10102.8 (2)
C7—C2—C3—C41.4 (3)C11A—O2—C10—O32.1 (6)
C1—C2—C3—C4179.5 (2)C11B—O2—C10—O3−15.4 (11)
C2—C3—C4—C5−0.3 (3)C11A—O2—C10—C9−176.9 (5)
C2—C3—C4—Br−179.94 (16)C11B—O2—C10—C9165.7 (10)
C3—C4—C5—C6−0.5 (4)C8—C9—C10—O324.4 (4)
Br—C4—C5—C6179.14 (18)C8—C9—C10—O2−156.7 (2)
C4—C5—C6—C70.1 (4)C10—O2—C11A—C12A174.3 (5)
C8—O1—C7—C6−179.6 (2)C11B—O2—C11A—C12A−74 (4)
C8—O1—C7—C20.8 (2)O2—C11A—C12A—C13A−78.9 (8)
C5—C6—C7—O1−178.5 (2)C11A—C12A—C13A—C14A−172.1 (9)
C5—C6—C7—C21.1 (4)C10—O2—C11B—C12B128.1 (15)
C3—C2—C7—O1177.69 (19)C11A—O2—C11B—C12B51 (3)
C1—C2—C7—O1−0.9 (2)O2—C11B—C12B—C13B69 (3)
C3—C2—C7—C6−1.9 (3)C11B—C12B—C13B—C14B−171 (3)
C1—C2—C7—C6179.5 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C12A—H12A···Cgi0.972.783.698 (5)158
C5—H5···O3ii0.932.553.405 (3)153
C9—H9B···O4iii0.972.303.248 (3)167

Symmetry codes: (i) x+1, y+1, z; (ii) −x, −y+1, −z; (iii) −x+1, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2347).

References

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