Acta Cryst. (2009). E65, o1311 [ doi:10.1107/S1600536809017930 ]
The title compound, C15H12O2S, features three fused rings with a dihedral angle of 79.6 (2)° between the isopropenyl group and the thiophene ring. In the crystal, molecules are connected into a supramolecular helical chain via C-H
O contacts.
A mixture of 7-mercapto-4-methyl-2H-chromen-2-one (961 mg, 5 mmol), 2-methylbut-3-yn-2-ol (6 ml, 60 mmol) and pyridinium p-toluenesulphonate (90 mg, 0.36 mmol) in dry toluene (30 ml) was refluxed for 6 h. After the toluene was evaporated in vacuo, the residue was purified by silica gel column chromatography (petroleum ether / acetone = 15 / 1) to afford 260 mg of (I); yield 21.3%. Recrystallization from isopropyl ether gave colourless crystals.
All H atoms were placed in the idealized positions with C—H = 0.93— 0.96 Å, and with Uiso(H) = 1.2—1.5 Ueq(C).
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
![[Figure 1]](./tk2449fig1thm.gif)
| Fig. 1. The molecular structure of (I), with atom labels and 30% probability displacement ellipsoids for non-H atoms. |
| C15H12O2S | F000 = 536 |
| Mr = 256.31 | Dx = 1.346 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 812 reflections |
| a = 8.547 (2) Å | θ = 3.1–27.4º |
| b = 11.425 (3) Å | µ = 0.25 mm−1 |
| c = 13.641 (4) Å | T = 293 K |
| β = 108.259 (19)º | Block, yellow |
| V = 1265.0 (6) Å3 | 0.50 × 0.15 × 0.12 mm |
| Z = 4 |
| Bruker SMART CCD area-detector diffractometer | 2698 independent reflections |
| Radiation source: fine-focus sealed tube | 1870 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.091 |
| T = 293 K | θmax = 27.0º |
| φ and ω scans | θmin = 2.4º |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −10→10 |
| Tmin = 0.887, Tmax = 0.971 | k = −11→14 |
| 5816 measured reflections | l = −14→17 |
| Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
| Least-squares matrix: full | H-atom parameters constrained |
| R[F2 > 2σ(F2)] = 0.068 | w = 1/[σ2(Fo2) + (0.1022P)2P] where P = (Fo2 + 2Fc2)/3 |
| wR(F2) = 0.177 | (Δ/σ)max < 0.001 |
| S = 0.99 | Δρmax = 0.37 e Å−3 |
| 2698 reflections | Δρmin = −0.44 e Å−3 |
| 166 parameters | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
| Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.021 (5) |
| Secondary atom site location: difference Fourier map |
| C15H12O2S | V = 1265.0 (6) Å3 |
| Mr = 256.31 | Z = 4 |
| Monoclinic, P21/c | Mo Kα |
| a = 8.547 (2) Å | µ = 0.25 mm−1 |
| b = 11.425 (3) Å | T = 293 K |
| c = 13.641 (4) Å | 0.50 × 0.15 × 0.12 mm |
| β = 108.259 (19)º |
| Bruker SMART CCD area-detector diffractometer | 2698 independent reflections |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1870 reflections with I > 2σ(I) |
| Tmin = 0.887, Tmax = 0.971 | Rint = 0.091 |
| 5816 measured reflections |
| R[F2 > 2σ(F2)] = 0.068 | 166 parameters |
| wR(F2) = 0.177 | H-atom parameters constrained |
| S = 0.99 | Δρmax = 0.37 e Å−3 |
| 2698 reflections | Δρmin = −0.44 e Å−3 |
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. |
| x | y | z | Uiso*/Ueq | ||
| S1 | 0.97805 (8) | −0.09812 (6) | 0.19803 (5) | 0.0637 (3) | |
| O1 | 0.65111 (17) | 0.10433 (13) | 0.38658 (11) | 0.0495 (4) | |
| O2 | 0.4812 (2) | 0.18035 (18) | 0.46125 (14) | 0.0719 (6) | |
| C1 | 0.6213 (3) | 0.1761 (2) | 0.45948 (18) | 0.0526 (6) | |
| C2 | 0.7579 (3) | 0.2386 (2) | 0.52571 (17) | 0.0563 (6) | |
| H2 | 0.7401 | 0.2892 | 0.5745 | 0.068* | |
| C3 | 0.9108 (3) | 0.22726 (19) | 0.52044 (17) | 0.0486 (6) | |
| C4 | 0.9398 (3) | 0.14773 (18) | 0.44540 (15) | 0.0411 (5) | |
| C5 | 1.0960 (3) | 0.12728 (19) | 0.43491 (17) | 0.0464 (5) | |
| H5 | 1.1872 | 0.1650 | 0.4793 | 0.056* | |
| C6 | 1.1173 (3) | 0.0535 (2) | 0.36125 (17) | 0.0498 (6) | |
| H6 | 1.2213 | 0.0407 | 0.3552 | 0.060* | |
| C7 | 0.9796 (3) | −0.0016 (2) | 0.29585 (16) | 0.0457 (5) | |
| C8 | 0.8207 (2) | 0.01396 (19) | 0.30220 (15) | 0.0431 (5) | |
| C9 | 0.8056 (3) | 0.09080 (17) | 0.37904 (16) | 0.0415 (5) | |
| C10 | 0.6986 (3) | −0.0519 (2) | 0.22558 (17) | 0.0520 (6) | |
| C11 | 0.7694 (3) | −0.1131 (2) | 0.1659 (2) | 0.0627 (7) | |
| H11 | 0.7089 | −0.1598 | 0.1114 | 0.075* | |
| C12 | 0.5195 (3) | −0.0597 (2) | 0.21115 (19) | 0.0587 (7) | |
| C13 | 0.4143 (4) | −0.0004 (4) | 0.1349 (3) | 0.1030 (12) | |
| H13A | 0.3015 | −0.0075 | 0.1233 | 0.124* | |
| H13B | 0.4534 | 0.0484 | 0.0931 | 0.124* | |
| C14 | 0.4693 (4) | −0.1369 (3) | 0.2794 (3) | 0.0912 (10) | |
| H14A | 0.3512 | −0.1377 | 0.2605 | 0.137* | |
| H14B | 0.5147 | −0.1099 | 0.3492 | 0.137* | |
| H14C | 0.5084 | −0.2146 | 0.2738 | 0.137* | |
| C15 | 1.0528 (3) | 0.2947 (2) | 0.5901 (2) | 0.0675 (8) | |
| H15A | 1.0157 | 0.3400 | 0.6378 | 0.101* | |
| H15B | 1.0967 | 0.3460 | 0.5496 | 0.101* | |
| H15C | 1.1369 | 0.2412 | 0.6277 | 0.101* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| S1 | 0.0501 (5) | 0.0779 (5) | 0.0685 (5) | −0.0039 (3) | 0.0261 (4) | −0.0209 (3) |
| O1 | 0.0338 (9) | 0.0599 (10) | 0.0531 (9) | 0.0017 (7) | 0.0113 (7) | −0.0063 (7) |
| O2 | 0.0453 (11) | 0.0963 (14) | 0.0778 (12) | 0.0071 (9) | 0.0246 (10) | −0.0110 (10) |
| C1 | 0.0417 (14) | 0.0603 (14) | 0.0555 (13) | 0.0080 (11) | 0.0149 (11) | 0.0032 (11) |
| C2 | 0.0582 (16) | 0.0567 (14) | 0.0545 (13) | 0.0085 (12) | 0.0184 (12) | −0.0063 (11) |
| C3 | 0.0488 (14) | 0.0448 (12) | 0.0494 (12) | 0.0008 (10) | 0.0114 (11) | 0.0021 (10) |
| C4 | 0.0392 (12) | 0.0405 (10) | 0.0426 (10) | −0.0018 (9) | 0.0112 (9) | 0.0036 (9) |
| C5 | 0.0368 (12) | 0.0475 (11) | 0.0524 (12) | −0.0077 (10) | 0.0102 (10) | 0.0029 (10) |
| C6 | 0.0350 (12) | 0.0567 (13) | 0.0595 (13) | −0.0025 (11) | 0.0177 (10) | 0.0033 (11) |
| C7 | 0.0408 (12) | 0.0519 (12) | 0.0465 (11) | −0.0004 (10) | 0.0168 (10) | 0.0007 (10) |
| C8 | 0.0358 (11) | 0.0476 (12) | 0.0450 (11) | 0.0003 (9) | 0.0112 (10) | 0.0023 (9) |
| C9 | 0.0339 (12) | 0.0459 (11) | 0.0453 (11) | 0.0026 (9) | 0.0134 (10) | 0.0059 (9) |
| C10 | 0.0409 (13) | 0.0607 (14) | 0.0498 (12) | 0.0034 (11) | 0.0078 (10) | −0.0060 (11) |
| C11 | 0.0472 (15) | 0.0769 (17) | 0.0603 (14) | 0.0012 (12) | 0.0114 (12) | −0.0201 (13) |
| C12 | 0.0366 (13) | 0.0708 (16) | 0.0617 (14) | 0.0009 (12) | 0.0054 (12) | −0.0187 (13) |
| C13 | 0.0510 (18) | 0.118 (3) | 0.121 (3) | 0.0160 (19) | −0.0002 (18) | 0.019 (2) |
| C14 | 0.0461 (17) | 0.118 (3) | 0.111 (2) | −0.0068 (18) | 0.0273 (18) | 0.012 (2) |
| C15 | 0.0649 (18) | 0.0664 (16) | 0.0681 (16) | −0.0130 (13) | 0.0165 (14) | −0.0224 (13) |
| S1—C11 | 1.706 (3) | C7—C8 | 1.399 (3) |
| S1—C7 | 1.728 (2) | C8—C9 | 1.404 (3) |
| O1—C9 | 1.365 (2) | C8—C10 | 1.437 (3) |
| O1—C1 | 1.373 (3) | C10—C11 | 1.351 (3) |
| O2—C1 | 1.205 (3) | C10—C12 | 1.484 (3) |
| C1—C2 | 1.424 (3) | C11—H11 | 0.9300 |
| C2—C3 | 1.338 (3) | C12—C13 | 1.328 (4) |
| C2—H2 | 0.9300 | C12—C14 | 1.442 (4) |
| C3—C4 | 1.447 (3) | C13—H13A | 0.9300 |
| C3—C15 | 1.499 (3) | C13—H13B | 0.9300 |
| C4—C9 | 1.381 (3) | C14—H14A | 0.9600 |
| C4—C5 | 1.406 (3) | C14—H14B | 0.9600 |
| C5—C6 | 1.367 (3) | C14—H14C | 0.9600 |
| C5—H5 | 0.9300 | C15—H15A | 0.9600 |
| C6—C7 | 1.385 (3) | C15—H15B | 0.9600 |
| C6—H6 | 0.9300 | C15—H15C | 0.9600 |
| C11—S1—C7 | 90.94 (11) | O1—C9—C8 | 116.39 (18) |
| C9—O1—C1 | 121.72 (17) | C4—C9—C8 | 122.13 (19) |
| O2—C1—O1 | 116.7 (2) | C11—C10—C8 | 110.4 (2) |
| O2—C1—C2 | 126.1 (2) | C11—C10—C12 | 121.8 (2) |
| O1—C1—C2 | 117.21 (19) | C8—C10—C12 | 127.7 (2) |
| C3—C2—C1 | 122.6 (2) | C10—C11—S1 | 115.0 (2) |
| C3—C2—H2 | 118.7 | C10—C11—H11 | 122.5 |
| C1—C2—H2 | 118.7 | S1—C11—H11 | 122.5 |
| C2—C3—C4 | 119.1 (2) | C13—C12—C14 | 123.5 (3) |
| C2—C3—C15 | 121.8 (2) | C13—C12—C10 | 119.4 (3) |
| C4—C3—C15 | 119.1 (2) | C14—C12—C10 | 117.0 (2) |
| C9—C4—C5 | 118.38 (19) | C12—C13—H13A | 120.0 |
| C9—C4—C3 | 117.90 (19) | C12—C13—H13B | 120.0 |
| C5—C4—C3 | 123.7 (2) | H13A—C13—H13B | 120.0 |
| C6—C5—C4 | 121.8 (2) | C12—C14—H14A | 109.5 |
| C6—C5—H5 | 119.1 | C12—C14—H14B | 109.5 |
| C4—C5—H5 | 119.1 | H14A—C14—H14B | 109.5 |
| C5—C6—C7 | 118.1 (2) | C12—C14—H14C | 109.5 |
| C5—C6—H6 | 120.9 | H14A—C14—H14C | 109.5 |
| C7—C6—H6 | 120.9 | H14B—C14—H14C | 109.5 |
| C6—C7—C8 | 123.2 (2) | C3—C15—H15A | 109.5 |
| C6—C7—S1 | 125.92 (17) | C3—C15—H15B | 109.5 |
| C8—C7—S1 | 110.87 (16) | H15A—C15—H15B | 109.5 |
| C7—C8—C9 | 116.35 (19) | C3—C15—H15C | 109.5 |
| C7—C8—C10 | 112.72 (19) | H15A—C15—H15C | 109.5 |
| C9—C8—C10 | 130.9 (2) | H15B—C15—H15C | 109.5 |
| O1—C9—C4 | 121.46 (18) |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C11—H11···O2i | 0.93 | 2.44 | 3.293 (3) | 153 |
| Symmetry codes: (i) −x+1, y−1/2, −z+1/2. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| C11—H11···O2i | 0.93 | 2.44 | 3.293 (3) | 153 |
| Symmetry codes: (i) −x+1, y−1/2, −z+1/2. |
The authors acknowledge Professor Linhong Weng for fruitful discussions and the Department of Chemistry, Fudan University, for providing necessary facilities.
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Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
4-Methyl-7-(2-methylbut-3-yn-2-ylthio)-2H-chromen-2-one is a key intermediate in our study on synthesizing potential anti-HIV heterocyclic agents (Chen et al., 2004). We attempted to prepare this by the reaction of 7-mercapto-4-methyl-2H-chromen-2-one with 2-methylbut-3-yn-2-ol in the presence of a catalytic amount of p-toluenesulphonate in refluxing toluene. To our surprise, an unexpected product (I) was obtained, which was structurally characterized by 1H NMR, MS, HRMS. The molecular structure was confirmed by X-ray diffraction. The determination of the structure of (I) is important for discovering the mechanism of this unexpected reaction. The full structural details of (I) are reported herein.
The molecular structure of (I), Fig. 1, shows three fused rings. The C10–C11 and C12-C13 bond distances of 1.351 (3) and 1.328 (4) Å, respectively indicate typical C=C double bonds. The isopropenyl group and the thiophene ring make a dihedral angle of 79.6 (2)°, due to the charge repulsion between π-electrons of isopropenyl group and the lactone-oxygen lone pair of electron lactone as well as unfavourable steric interactions. The molecular packing is stabilized by C—H···O contacts that link molecules into a supramolecular helical chain along the b-axis (Table 1).