organic compounds
2-(3-Methylsulfanyl-5-propyl-1-benzofuran-2-yl)acetic acid
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
The title compound, C14H16O3S, was prepared by alkaline hydrolysis of ethyl 2-(3-methylsulfanyl-5-propyl-1-benzofuran-2-yl)acetate. In the the carboxyl groups are involved in intermolecular O—H⋯O hydrogen bonds, which link the molecules into centrosymmetric dimers. These dimers are further packed into stacks along the a axis by weak C—H⋯π interactions.
Related literature
For the crystal structures of similar 2-(3-methylsulfanyl-1-benzofuran-2-yl) acetic acid derivatives, see: Seo et al. (2007); Choi et al. (2008).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: SMART (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; 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.
Supporting information
10.1107/S1600536809012124/zl2191sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809012124/zl2191Isup2.hkl
Ethyl 2-(3-methylsulfanyl-5-propyl-1-benzofuran-2-yl)acetate (334 mg, 1.2 mmol) was added to a solution of potassium hydroxide (337 mg, 6.0 mmol) in water (20 ml) and methanol (20 ml), and the mixture was refluxed for 5h, then cooled. 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 δ 0.96 (t, J = 7.32 Hz, 3H), 1.64-1.73 (m, 2H), 2.33 (s, 3H), 2.70 (t, J = 7.68 Hz, 2H), 4.03 (s, 2H), 7.13 (dd, J = 8.44 Hz and 1.44 Hz, 1H), 7.36 (d, J = 8.44 Hz, 1H), 7.43 (s, 1H), 10.02 (s, 1H); EI-MS 264 [M+].
(ethyl acetate) to afford the title compound as a colorless solid [yield 84%, m.p. 395-396 K; Rf = 0.78 (ethyl acetate)]. Single crystals suitable for X-ray diffraction were prepared by evaporation of a solution of the title compound in diisopropyl ether at room temperature. Spectroscopic analysis: 1H NMR (CDCl3, 400 MHz)All H atoms were geometrically positioned and refined using a riding model, with C—H = 0.93 (aromatic), 0.97 (methylene), 0.96 Å (methyl) H atoms, and O—H = 0.82 respectively, and with Uiso(H) = 1.2Ueq(C) (aromatic, methylene), 1.5Ueq(C) (methyl), and 1.5Ueq(O) H atoms.
Data collection: SMART (Bruker, 2001); cell
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).C14H16O3S | Z = 2 |
Mr = 264.33 | F(000) = 280 |
Triclinic, P1 | Dx = 1.260 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71069 Å |
a = 5.1727 (6) Å | Cell parameters from 1161 reflections |
b = 8.173 (1) Å | θ = 2.5–22.1° |
c = 16.614 (2) Å | µ = 0.23 mm−1 |
α = 94.321 (2)° | T = 298 K |
β = 95.831 (2)° | Block, colorless |
γ = 91.110 (2)° | 0.20 × 0.20 × 0.05 mm |
V = 696.50 (14) Å3 |
Bruker SMART CCD diffractometer | 1425 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.049 |
Graphite monochromator | θmax = 25.0°, θmin = 2.5° |
Detector resolution: 10.0 pixels mm-1 | h = −5→6 |
ϕ and ω scans | k = −9→9 |
3658 measured reflections | l = −19→14 |
2389 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.059 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.151 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0531P)2 + 0.2044P] where P = (Fo2 + 2Fc2)/3 |
2389 reflections | (Δ/σ)max < 0.001 |
165 parameters | Δρmax = 0.21 e Å−3 |
0 restraints | Δρmin = −0.24 e Å−3 |
C14H16O3S | γ = 91.110 (2)° |
Mr = 264.33 | V = 696.50 (14) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.1727 (6) Å | Mo Kα radiation |
b = 8.173 (1) Å | µ = 0.23 mm−1 |
c = 16.614 (2) Å | T = 298 K |
α = 94.321 (2)° | 0.20 × 0.20 × 0.05 mm |
β = 95.831 (2)° |
Bruker SMART CCD diffractometer | 1425 reflections with I > 2σ(I) |
3658 measured reflections | Rint = 0.049 |
2389 independent reflections |
R[F2 > 2σ(F2)] = 0.059 | 0 restraints |
wR(F2) = 0.151 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.21 e Å−3 |
2389 reflections | Δρmin = −0.24 e Å−3 |
165 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
S | −0.09603 (19) | 0.20796 (12) | 0.21468 (7) | 0.0768 (4) | |
O1 | 0.1105 (4) | 0.5482 (3) | 0.39156 (13) | 0.0636 (6) | |
O2 | 0.1260 (5) | 0.1733 (3) | 0.45463 (16) | 0.0851 (9) | |
H2O | 0.1607 | 0.0891 | 0.4769 | 0.128* | |
O3 | −0.2757 (4) | 0.0916 (3) | 0.46894 (16) | 0.0785 (8) | |
C1 | 0.0362 (6) | 0.3712 (4) | 0.2809 (2) | 0.0520 (8) | |
C2 | 0.2351 (6) | 0.4892 (4) | 0.26600 (19) | 0.0516 (8) | |
C3 | 0.3818 (6) | 0.5128 (4) | 0.2021 (2) | 0.0591 (9) | |
H3 | 0.3590 | 0.4425 | 0.1552 | 0.071* | |
C4 | 0.5633 (6) | 0.6423 (4) | 0.2089 (2) | 0.0627 (10) | |
C5 | 0.5902 (7) | 0.7445 (4) | 0.2808 (3) | 0.0711 (10) | |
H5 | 0.7094 | 0.8322 | 0.2852 | 0.085* | |
C6 | 0.4507 (7) | 0.7226 (4) | 0.3450 (2) | 0.0708 (10) | |
H6 | 0.4752 | 0.7910 | 0.3926 | 0.085* | |
C7 | 0.2718 (6) | 0.5937 (4) | 0.3353 (2) | 0.0556 (8) | |
C8 | −0.0298 (6) | 0.4115 (4) | 0.3551 (2) | 0.0546 (8) | |
C9 | 0.7208 (8) | 0.6706 (5) | 0.1400 (2) | 0.0824 (12) | |
H9A | 0.8818 | 0.7278 | 0.1618 | 0.099* | |
H9B | 0.7653 | 0.5649 | 0.1153 | 0.099* | |
C10 | 0.5895 (10) | 0.7662 (7) | 0.0762 (3) | 0.1197 (18) | |
H10A | 0.5433 | 0.8713 | 0.1011 | 0.144* | |
H10B | 0.4293 | 0.7084 | 0.0542 | 0.144* | |
C11 | 0.7458 (12) | 0.7960 (8) | 0.0082 (3) | 0.146 (2) | |
H11A | 0.8735 | 0.8817 | 0.0253 | 0.219* | |
H11B | 0.6335 | 0.8284 | −0.0371 | 0.219* | |
H11C | 0.8314 | 0.6972 | −0.0075 | 0.219* | |
C12 | −0.2179 (6) | 0.3359 (4) | 0.4048 (2) | 0.0619 (9) | |
H12A | −0.3761 | 0.3045 | 0.3702 | 0.074* | |
H12B | −0.2620 | 0.4176 | 0.4463 | 0.074* | |
C13 | −0.1180 (6) | 0.1878 (4) | 0.44510 (19) | 0.0545 (8) | |
C14 | 0.1689 (8) | 0.0703 (5) | 0.2223 (3) | 0.1078 (16) | |
H14A | 0.3270 | 0.1278 | 0.2146 | 0.162* | |
H14B | 0.1370 | −0.0192 | 0.1813 | 0.162* | |
H14C | 0.1847 | 0.0284 | 0.2749 | 0.162* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S | 0.0644 (7) | 0.0620 (6) | 0.1009 (8) | −0.0190 (5) | 0.0062 (5) | −0.0057 (5) |
O1 | 0.0738 (16) | 0.0557 (14) | 0.0620 (15) | −0.0043 (12) | 0.0080 (12) | 0.0099 (11) |
O2 | 0.0554 (17) | 0.0877 (18) | 0.120 (2) | 0.0049 (13) | 0.0086 (14) | 0.0595 (16) |
O3 | 0.0556 (15) | 0.0722 (16) | 0.113 (2) | −0.0081 (12) | 0.0101 (13) | 0.0463 (15) |
C1 | 0.0513 (19) | 0.0419 (17) | 0.063 (2) | −0.0047 (14) | 0.0008 (16) | 0.0153 (15) |
C2 | 0.055 (2) | 0.0433 (17) | 0.057 (2) | −0.0015 (15) | −0.0005 (16) | 0.0152 (16) |
C3 | 0.062 (2) | 0.0521 (19) | 0.064 (2) | −0.0027 (16) | 0.0043 (17) | 0.0104 (16) |
C4 | 0.060 (2) | 0.054 (2) | 0.075 (3) | −0.0056 (17) | 0.0014 (18) | 0.0213 (19) |
C5 | 0.070 (2) | 0.049 (2) | 0.095 (3) | −0.0111 (18) | 0.004 (2) | 0.017 (2) |
C6 | 0.088 (3) | 0.0472 (19) | 0.075 (3) | −0.0126 (19) | 0.003 (2) | 0.0014 (18) |
C7 | 0.062 (2) | 0.0447 (17) | 0.061 (2) | −0.0007 (15) | 0.0056 (17) | 0.0111 (17) |
C8 | 0.055 (2) | 0.0487 (18) | 0.061 (2) | −0.0023 (15) | 0.0006 (16) | 0.0183 (16) |
C9 | 0.078 (3) | 0.079 (3) | 0.095 (3) | −0.012 (2) | 0.016 (2) | 0.030 (2) |
C10 | 0.135 (4) | 0.134 (4) | 0.105 (4) | 0.020 (3) | 0.041 (3) | 0.056 (3) |
C11 | 0.190 (6) | 0.151 (5) | 0.107 (4) | −0.005 (5) | 0.046 (4) | 0.042 (4) |
C12 | 0.055 (2) | 0.060 (2) | 0.075 (2) | 0.0041 (16) | 0.0076 (17) | 0.0286 (18) |
C13 | 0.045 (2) | 0.058 (2) | 0.063 (2) | 0.0015 (16) | 0.0080 (16) | 0.0191 (16) |
C14 | 0.080 (3) | 0.059 (2) | 0.183 (5) | −0.007 (2) | 0.031 (3) | −0.020 (3) |
S—C1 | 1.746 (3) | C6—H6 | 0.9300 |
S—C14 | 1.791 (4) | C8—C12 | 1.493 (4) |
O1—C7 | 1.381 (4) | C9—C10 | 1.482 (5) |
O1—C8 | 1.385 (4) | C9—H9A | 0.9700 |
O2—C13 | 1.265 (3) | C9—H9B | 0.9700 |
O2—H2O | 0.8200 | C10—C11 | 1.487 (6) |
O3—C13 | 1.237 (4) | C10—H10A | 0.9700 |
C1—C8 | 1.332 (4) | C10—H10B | 0.9700 |
C1—C2 | 1.448 (4) | C11—H11A | 0.9600 |
C2—C7 | 1.376 (4) | C11—H11B | 0.9600 |
C2—C3 | 1.388 (4) | C11—H11C | 0.9600 |
C3—C4 | 1.392 (4) | C12—C13 | 1.501 (4) |
C3—H3 | 0.9300 | C12—H12A | 0.9700 |
C4—C5 | 1.399 (5) | C12—H12B | 0.9700 |
C4—C9 | 1.499 (5) | C14—H14A | 0.9600 |
C5—C6 | 1.368 (5) | C14—H14B | 0.9600 |
C5—H5 | 0.9300 | C14—H14C | 0.9600 |
C6—C7 | 1.377 (4) | ||
C1—S—C14 | 99.71 (17) | C10—C9—H9B | 108.6 |
C7—O1—C8 | 105.5 (2) | C4—C9—H9B | 108.6 |
C13—O2—H2O | 109.5 | H9A—C9—H9B | 107.6 |
C8—C1—C2 | 106.9 (3) | C9—C10—C11 | 114.8 (4) |
C8—C1—S | 126.0 (2) | C9—C10—H10A | 108.6 |
C2—C1—S | 127.1 (3) | C11—C10—H10A | 108.6 |
C7—C2—C3 | 119.6 (3) | C9—C10—H10B | 108.6 |
C7—C2—C1 | 105.4 (3) | C11—C10—H10B | 108.6 |
C3—C2—C1 | 135.0 (3) | H10A—C10—H10B | 107.5 |
C2—C3—C4 | 119.6 (3) | C10—C11—H11A | 109.5 |
C2—C3—H3 | 120.2 | C10—C11—H11B | 109.5 |
C4—C3—H3 | 120.2 | H11A—C11—H11B | 109.5 |
C3—C4—C5 | 118.0 (3) | C10—C11—H11C | 109.5 |
C3—C4—C9 | 120.2 (3) | H11A—C11—H11C | 109.5 |
C5—C4—C9 | 121.8 (3) | H11B—C11—H11C | 109.5 |
C6—C5—C4 | 123.6 (3) | C8—C12—C13 | 114.0 (3) |
C6—C5—H5 | 118.2 | C8—C12—H12A | 108.8 |
C4—C5—H5 | 118.2 | C13—C12—H12A | 108.8 |
C5—C6—C7 | 116.4 (3) | C8—C12—H12B | 108.8 |
C5—C6—H6 | 121.8 | C13—C12—H12B | 108.8 |
C7—C6—H6 | 121.8 | H12A—C12—H12B | 107.7 |
C2—C7—C6 | 122.9 (3) | O3—C13—O2 | 124.3 (3) |
C2—C7—O1 | 110.5 (3) | O3—C13—C12 | 118.8 (3) |
C6—C7—O1 | 126.6 (3) | O2—C13—C12 | 116.9 (3) |
C1—C8—O1 | 111.7 (3) | S—C14—H14A | 109.5 |
C1—C8—C12 | 132.2 (3) | S—C14—H14B | 109.5 |
O1—C8—C12 | 116.1 (3) | H14A—C14—H14B | 109.5 |
C10—C9—C4 | 114.6 (3) | S—C14—H14C | 109.5 |
C10—C9—H9A | 108.6 | H14A—C14—H14C | 109.5 |
C4—C9—H9A | 108.6 | H14B—C14—H14C | 109.5 |
C14—S—C1—C8 | −106.1 (3) | C5—C6—C7—C2 | 1.1 (5) |
C14—S—C1—C2 | 74.5 (3) | C5—C6—C7—O1 | 179.9 (3) |
C8—C1—C2—C7 | 0.0 (3) | C8—O1—C7—C2 | −0.2 (3) |
S—C1—C2—C7 | 179.5 (2) | C8—O1—C7—C6 | −179.0 (3) |
C8—C1—C2—C3 | 179.1 (3) | C2—C1—C8—O1 | −0.1 (3) |
S—C1—C2—C3 | −1.4 (5) | S—C1—C8—O1 | −179.6 (2) |
C7—C2—C3—C4 | −0.3 (5) | C2—C1—C8—C12 | −178.7 (3) |
C1—C2—C3—C4 | −179.4 (3) | S—C1—C8—C12 | 1.8 (5) |
C2—C3—C4—C5 | 0.0 (5) | C7—O1—C8—C1 | 0.2 (3) |
C2—C3—C4—C9 | −179.2 (3) | C7—O1—C8—C12 | 179.0 (3) |
C3—C4—C5—C6 | 0.9 (5) | C3—C4—C9—C10 | 83.8 (5) |
C9—C4—C5—C6 | −179.8 (3) | C5—C4—C9—C10 | −95.4 (5) |
C4—C5—C6—C7 | −1.5 (5) | C4—C9—C10—C11 | 179.4 (5) |
C3—C2—C7—C6 | −0.3 (5) | C1—C8—C12—C13 | 79.2 (4) |
C1—C2—C7—C6 | 179.0 (3) | O1—C8—C12—C13 | −99.3 (3) |
C3—C2—C7—O1 | −179.2 (3) | C8—C12—C13—O3 | −160.9 (3) |
C1—C2—C7—O1 | 0.1 (3) | C8—C12—C13—O2 | 21.3 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···O3i | 0.82 | 1.86 | 2.679 (3) | 174 |
C12—H12A···Cgii | 0.97 | 3.04 | 3.770 (3) | 133 |
Symmetry codes: (i) −x, −y, −z+1; (ii) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C14H16O3S |
Mr | 264.33 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 298 |
a, b, c (Å) | 5.1727 (6), 8.173 (1), 16.614 (2) |
α, β, γ (°) | 94.321 (2), 95.831 (2), 91.110 (2) |
V (Å3) | 696.50 (14) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.23 |
Crystal size (mm) | 0.20 × 0.20 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART CCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3658, 2389, 1425 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.059, 0.151, 1.06 |
No. of reflections | 2389 |
No. of parameters | 165 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.24 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···O3i | 0.82 | 1.86 | 2.679 (3) | 173.7 |
C12—H12A···Cgii | 0.97 | 3.04 | 3.770 (3) | 133.0 |
Symmetry codes: (i) −x, −y, −z+1; (ii) x−1, y, z. |
References
Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2001). SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Choi, H. D., Seo, P. J., Son, B. W. & Lee, U. (2008). Acta Cryst. E64, o1598. Web of Science CSD CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Seo, P. J., Choi, H. D., Son, B. W. & Lee, U. (2007). Acta Cryst. E63, o2048–o2049. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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This work is related to our communications on the synthesis and structure of 2-(3-methylsulfanyl-1-benzofuran-2-yl)acetic acid derivatives, viz. 2-(5-ethyl-3-methylsulfanyl-1-benzofuran-2-yl)acetic acid (Seo et al., 2007) and 2-(5,7-dimethyl-3-methylsulfanyl-1-benzofuran-2-yl)acetic acid (Choi et al., 2008). Here we report the crystal structure of the title compound, 2-(3-methylsulfanyl-5-propyl-1-benzofuran-2-yl)acetic acid (Fig. 1).
The benzofuran unit is essentially planar, with a mean deviation of 0.005 (3) Å from the least-squares plane defined by the nine constituent atoms. In the crystal structure, the carboxyl groups are involved in intermolecular O—H···O hydrogen bonds (Fig. 2 and Table 1; symmetry code as in Fig. 2), which link the molecules into centrosymmetric dimers. These dimers are further packed into stacks along the a-axis by weak C—H···π interactions, with a C12—H12A···Cgii separation of 3.04 Å (Fig. 2 and Table 1; Cg is the centroid of the C1/C2/C7/O1/C8 furan ring, symmetry code as in Fig. 2).