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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 9| September 2009| Page o2268
doi:10.1107/S1600536809033765

2-(5-Methyl-3-methyl­sulfinyl-1-benzo­furan-2-yl)acetic acid

Hong Dae Choi,a Pil Ja Seo,a Byeng Wha Sonb and Uk Leeb*

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

(Received 6 August 2009; accepted 24 August 2009; online 29 August 2009)

In the title compound, C12H12O4S, the O atom and the methyl group of the methyl­sulfinyl substituent are located on opposite sides of the plane of the benzofuran fragment. In the crystal structure, inter­molecular C—H⋯O and O—H⋯O hydrogen-bonding inter­actions are found. The structure also exhibits aromatic π–π inter­actions between the furan and benzene rings [centroid–centroid distance = 3.841 (5) Å].

Related literature

For the crystal structures of similar alkyl 2-(5-methyl-3-methyl­sulfinyl-1-benzofuran-2-yl)acetate derivatives, see: Choi et al. (2008a[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008a). Acta Cryst. E64, o1711.],b[Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008b). Acta Cryst. E64, o2079.]). For the pharmacological properties of benzofuran compounds, see: Howlett et al. (1999[Howlett, D. R., Perry, A. E., Godfrey, F., Swatton, J. E., Jennings, K. H., Spitzfaden, C., Wadsworth, H., Wood, S. J. & Markwell, R. E. (1999). Biochem. J. 340, 283-289.]); Twyman & Allsop (1999[Twyman, L. J. & Allsop, D. (1999). Tetrahedron Lett. 40, 9383-9384.]). For natural products that contain benzofuran ring systems, see: Akgul & Anil (2003[Akgul, Y. Y. & Anil, H. (2003). Phytochemistry, 63, 939-943.]); von Reuss & König (2004[Reuss, S. H. von & König, W. A. (2004). Phytochemistry, 65, 3113-3118.]).

[Scheme 1]

Experimental

Crystal data

  • C12H12O4S

  • Mr = 252.28

  • Orthorhombic, P b c a

  • a = 7.767 (1) Å

  • b = 16.248 (2) Å

  • c = 18.733 (2) Å

  • V = 2364.1 (5) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.27 mm−1

  • T = 293 K

  • 0.40 × 0.20 × 0.05 mm
Data collection

  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2000[Sheldrick, G. M. (2000). SADABS. University of Göttingen, Germany.]) Tmin = 0.899, Tmax = 0.987

  • 13669 measured reflections

  • 2690 independent reflections

  • 1461 reflections with I > 2σ(I)

  • Rint = 0.110
Refinement

  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.156

  • S = 1.04

  • 2690 reflections

  • 160 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.45 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C9—H9B⋯O4i 0.97 2.48 3.339 (5) 148
O2—H2⋯O4ii 0.85 (6) 1.74 (6) 2.590 (4) 175 (5)
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]; (ii) x+1, y, z.

Data collection: SMART (Bruker, 2001[Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SAINT and SMART. 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 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 1998[Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809033765/nc2155sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809033765/nc2155Isup2.hkl

checkCIF report


Comment top

Molecules containing benzofuran skeletons have been received considerable attention in the field of their pharmacological properties (Howlett et al., 1999; Twyman & Allsop, 1999) and often occurs as natural products (Akgul & Anil, 2003; von Reuss & König, 2004). As part of our ongoing studies on the synthesis and structure of such compounds the structure of the title compound is reported (Choi et al., 2008a,b).

The benzofuran unit is essentially planar, with a mean deviation of 0.013 (3) Å from the least-squares plane defined by the nine constituent atoms (Fig. 1). In the crystal structure intermolecualr C–H···O and O–H···O hydrogen bonding interactions are found (Fig. 2 and Table 1). The crystal structure is further stabilized by aromatic π···π interactions between the furan and the benzene rings of adjacent molecules, with a Cg1···Cg2iii distance of 3.841 (5) Å (Cg1 and Cg2 are the centroids of the C1/C2/C7/O1/C8 furan ring and the C2-C7 benzene ring, respectively (Fig. 2).

Related literature top

For the crystal structures of similar alkyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate derivatives, see: Choi et al. (2008a,b). For the pharmacological properties of benzofuran compounds, see: Howlett et al. (1999); Twyman & Allsop (1999). For natural products that contain benzofuran ring systems, see: Akgul & Anil (2003); von Reuss & König (2004).

Experimental top

Ethyl 2-(5-methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetate (303 mg, 1.2 mmol) was added to a solution of potassium hydroxide (337 mg, 6 mmol) in water (15 ml) and methanol (15 ml), and the mixture was refluxed for 5h, then cooled down. Water was added, and the solution was extracted with dichloromethane. The aqueous layer was acidified to pH 1 with concentrated hydrochloric acid and then extracted with chloroform, dried over magnesium sulfate, filtered and concentrated under vacuum. The residue was purified by column chromatography (ethanol) to afford the title compound as a colorless solid [yield 84%, m.p. 461-462 K; Rf = 0.51 (ethanol)]. Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in acetone at room temperature.

Refinement top

Atom H2 of the hydroxy group was found in a difference Fourier map and refined freely. The other H atoms were positioned with idealized geometry and were refined using a riding model, with C-H = 0.93 Å for aromatic H atoms, 0.97 Å for methylene H atoms and 0.96 Å for methyl H atoms, respectively, and with Uiso(H) = 1.2Ueq(C) for aromatic and methylene H atoms and 1.5Ueq(C) for methyl H atoms.

Computing details top

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

Figures top
[Figure 1] 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.
[Figure 2] Fig. 2. C–H···O, O–H···O, and π···π interactions (dotted lines) in the structure of the title compound. Cg denotes the ring centroid. [Symmetry codes: (i) - x + 2, - y + 1, - z + 1; (ii) x + 1/2, - y + 3/2, - z + 1; (iii) x + 1, y, z; (iv) x - 1/2, - y + 3/2, - z + 1; (v) x - 1, y, z.]
2-(5-Methyl-3-methylsulfinyl-1-benzofuran-2-yl)acetic acid top
Crystal data top
C12H12O4SDx = 1.418 Mg m−3
Mr = 252.28Melting point = 461–462 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2314 reflections
a = 7.767 (1) Åθ = 2.7–23.2°
b = 16.248 (2) ŵ = 0.27 mm−1
c = 18.733 (2) ÅT = 293 K
V = 2364.1 (5) Å3Block, colorless
Z = 80.40 × 0.20 × 0.05 mm
F(000) = 1056
Data collection top
Bruker SMART CCD
diffractometer		2690 independent reflections
Radiation source: fine-focus sealed tube1461 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.110
Detector resolution: 10.0 pixels mm-1θmax = 27.5°, θmin = 2.2°
ϕ and ω scansh = −8→10
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)		k = −20→21
Tmin = 0.899, Tmax = 0.987l = −24→24
13669 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)] = 0.052Hydrogen site location: difference Fourier map
wR(F2) = 0.156H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0469P)2 + 5.6706P]
where P = (Fo2 + 2Fc2)/3
2690 reflections(Δ/σ)max < 0.001
160 parametersΔρmax = 0.35 e Å−3
0 restraintsΔρmin = −0.45 e Å−3
Crystal data top
C12H12O4SV = 2364.1 (5) Å3
Mr = 252.28Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 7.767 (1) ŵ = 0.27 mm−1
b = 16.248 (2) ÅT = 293 K
c = 18.733 (2) Å0.40 × 0.20 × 0.05 mm
Data collection top
Bruker SMART CCD
diffractometer		2690 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2000)		1461 reflections with I > 2σ(I)
Tmin = 0.899, Tmax = 0.987Rint = 0.110
13669 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.156H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.35 e Å−3
2690 reflectionsΔρmin = −0.45 e Å−3
160 parameters
Special details top

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
S0.11771 (12)0.71553 (6)0.38153 (5)0.0201 (2)
O10.2472 (3)0.49764 (16)0.45410 (13)0.0239 (6)
O20.6841 (4)0.67768 (18)0.46398 (15)0.0285 (7)
H20.761 (7)0.697 (3)0.437 (3)0.057 (17)*
O30.5236 (4)0.6591 (2)0.36700 (15)0.0429 (9)
O4−0.0703 (3)0.73974 (16)0.38751 (15)0.0304 (7)
C10.1334 (5)0.6112 (2)0.40470 (19)0.0198 (8)
C20.0240 (5)0.5428 (2)0.38493 (19)0.0206 (8)
C3−0.1287 (5)0.5323 (2)0.34684 (19)0.0232 (8)
H3−0.18370.57730.32630.028*
C4−0.1973 (5)0.4540 (2)0.3400 (2)0.0262 (9)
C5−0.1128 (5)0.3867 (2)0.3718 (2)0.0263 (9)
H5−0.15940.33440.36640.032*
C60.0363 (5)0.3956 (2)0.4107 (2)0.0238 (9)
H60.09100.35090.43170.029*
C70.1005 (5)0.4747 (2)0.41678 (19)0.0201 (8)
C80.2619 (5)0.5814 (2)0.44641 (18)0.0203 (8)
C90.4120 (5)0.6207 (2)0.48186 (19)0.0228 (9)
H9A0.46660.58060.51290.027*
H9B0.37130.66560.51150.027*
C100.5441 (5)0.6535 (2)0.4304 (2)0.0218 (8)
C11−0.3638 (6)0.4401 (3)0.2989 (2)0.0419 (12)
H11A−0.43950.48600.30620.063*
H11B−0.41830.39070.31570.063*
H11C−0.33860.43480.24900.063*
C120.1561 (6)0.7075 (3)0.2878 (2)0.0349 (11)
H12A0.07700.66870.26740.052*
H12B0.27190.68910.27980.052*
H12C0.14000.76030.26590.052*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S0.0185 (5)0.0201 (4)0.0216 (4)−0.0006 (4)0.0017 (4)0.0006 (4)
O10.0196 (14)0.0243 (14)0.0278 (15)−0.0018 (11)−0.0061 (12)0.0021 (12)
O20.0196 (15)0.0405 (18)0.0254 (15)−0.0086 (13)−0.0019 (13)0.0023 (13)
O30.0280 (18)0.081 (2)0.0198 (15)−0.0110 (17)−0.0037 (13)0.0048 (15)
O40.0202 (15)0.0282 (15)0.0429 (17)0.0063 (12)0.0086 (13)0.0054 (13)
C10.020 (2)0.0197 (19)0.0195 (18)−0.0005 (16)0.0013 (16)−0.0011 (15)
C20.022 (2)0.024 (2)0.0159 (18)0.0014 (16)0.0032 (16)−0.0024 (16)
C30.023 (2)0.025 (2)0.0217 (19)0.0007 (18)−0.0037 (17)0.0020 (16)
C40.024 (2)0.035 (2)0.0197 (19)−0.0046 (19)−0.0036 (17)−0.0004 (18)
C50.033 (2)0.0207 (19)0.025 (2)−0.0072 (19)0.0007 (19)−0.0001 (16)
C60.024 (2)0.021 (2)0.026 (2)0.0005 (17)−0.0034 (18)0.0047 (16)
C70.018 (2)0.025 (2)0.0181 (18)0.0005 (17)−0.0005 (16)−0.0006 (15)
C80.020 (2)0.025 (2)0.0169 (18)−0.0017 (16)0.0018 (16)−0.0024 (16)
C90.021 (2)0.028 (2)0.0186 (18)−0.0006 (17)−0.0023 (16)−0.0018 (16)
C100.0144 (19)0.029 (2)0.0215 (19)0.0023 (17)−0.0009 (16)−0.0048 (16)
C110.037 (3)0.045 (3)0.044 (3)−0.013 (2)−0.019 (2)0.010 (2)
C120.034 (3)0.046 (3)0.025 (2)0.006 (2)0.0006 (18)0.005 (2)
Geometric parameters (Å, º) top
S—O41.516 (3)C4—C111.522 (6)
S—C11.754 (4)C5—C61.375 (6)
S—C121.786 (4)C5—H50.9300
O1—C81.374 (4)C6—C71.383 (5)
O1—C71.388 (4)C6—H60.9300
O2—C101.316 (5)C8—C91.486 (5)
O2—H20.85 (5)C9—C101.506 (5)
O3—C101.202 (4)C9—H9A0.9700
C1—C81.356 (5)C9—H9B0.9700
C1—C21.447 (5)C11—H11A0.9600
C2—C71.390 (5)C11—H11B0.9600
C2—C31.394 (5)C11—H11C0.9600
C3—C41.385 (5)C12—H12A0.9600
C3—H30.9300C12—H12B0.9600
C4—C51.408 (5)C12—H12C0.9600
O4—S—C1107.41 (17)O1—C7—C2110.7 (3)
O4—S—C12104.62 (19)C1—C8—O1110.7 (3)
C1—S—C1299.26 (19)C1—C8—C9133.0 (4)
C8—O1—C7106.3 (3)O1—C8—C9116.3 (3)
C10—O2—H2114 (3)C8—C9—C10113.6 (3)
C8—C1—C2107.8 (3)C8—C9—H9A108.8
C8—C1—S122.6 (3)C10—C9—H9A108.8
C2—C1—S129.7 (3)C8—C9—H9B108.8
C7—C2—C3119.1 (3)C10—C9—H9B108.8
C7—C2—C1104.5 (3)H9A—C9—H9B107.7
C3—C2—C1136.4 (4)O3—C10—O2124.0 (4)
C4—C3—C2119.1 (4)O3—C10—C9124.7 (4)
C4—C3—H3120.4O2—C10—C9111.3 (3)
C2—C3—H3120.4C4—C11—H11A109.5
C3—C4—C5119.6 (4)C4—C11—H11B109.5
C3—C4—C11120.7 (4)H11A—C11—H11B109.5
C5—C4—C11119.7 (4)C4—C11—H11C109.5
C6—C5—C4122.3 (4)H11A—C11—H11C109.5
C6—C5—H5118.8H11B—C11—H11C109.5
C4—C5—H5118.8S—C12—H12A109.5
C5—C6—C7116.5 (4)S—C12—H12B109.5
C5—C6—H6121.8H12A—C12—H12B109.5
C7—C6—H6121.8S—C12—H12C109.5
C6—C7—O1125.9 (3)H12A—C12—H12C109.5
C6—C7—C2123.3 (4)H12B—C12—H12C109.5
O4—S—C1—C8−138.0 (3)C8—O1—C7—C6−179.5 (4)
C12—S—C1—C8113.4 (3)C8—O1—C7—C20.8 (4)
O4—S—C1—C242.9 (4)C3—C2—C7—C62.4 (6)
C12—S—C1—C2−65.7 (4)C1—C2—C7—C6−179.6 (3)
C8—C1—C2—C7−0.9 (4)C3—C2—C7—O1−177.9 (3)
S—C1—C2—C7178.3 (3)C1—C2—C7—O10.1 (4)
C8—C1—C2—C3176.6 (4)C2—C1—C8—O11.5 (4)
S—C1—C2—C3−4.2 (7)S—C1—C8—O1−177.8 (2)
C7—C2—C3—C4−1.9 (5)C2—C1—C8—C9179.3 (4)
C1—C2—C3—C4−179.1 (4)S—C1—C8—C90.0 (6)
C2—C3—C4—C50.4 (6)C7—O1—C8—C1−1.4 (4)
C2—C3—C4—C11179.9 (4)C7—O1—C8—C9−179.6 (3)
C3—C4—C5—C60.8 (6)C1—C8—C9—C10−66.5 (5)
C11—C4—C5—C6−178.8 (4)O1—C8—C9—C10111.2 (4)
C4—C5—C6—C7−0.3 (6)C8—C9—C10—O310.1 (6)
C5—C6—C7—O1179.1 (3)C8—C9—C10—O2−171.7 (3)
C5—C6—C7—C2−1.2 (6)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9B···O4i0.972.483.339 (5)148
O2—H2···O4ii0.85 (6)1.74 (6)2.590 (4)175 (5)
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC12H12O4S
Mr252.28
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)7.767 (1), 16.248 (2), 18.733 (2)
V (Å3)2364.1 (5)
Z8
Radiation typeMo Kα
µ (mm−1)0.27
Crystal size (mm)0.40 × 0.20 × 0.05
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2000)
Tmin, Tmax0.899, 0.987
No. of measured, independent and
observed [I > 2σ(I)] reflections		13669, 2690, 1461
Rint0.110
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.156, 1.04
No. of reflections2690
No. of parameters160
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.35, −0.45

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9B···O4i0.972.483.339 (5)147.5
O2—H2···O4ii0.85 (6)1.74 (6)2.590 (4)175 (5)
Symmetry codes: (i) x+1/2, −y+3/2, −z+1; (ii) x+1, y, z.
 

References

First citationAkgul, Y. Y. & Anil, H. (2003). Phytochemistry, 63, 939–943.  Web of Science CrossRef PubMed CAS Google Scholar
 First citationBrandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationBruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 65| Part 9| September 2009| Page o2268
doi:10.1107/S1600536809033765
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