The title molecule, C20H20O4, lies on an inversion center. The central alkene moiety is not coplanar with the remainder of the molecule, forming a dihedral angle of 61.61 (12)° with the O-CH2-CH2-C plane and a dihedral angle of 58.70 (11)° with the phenyl plane. The central C=C length is 1.326 (2) Å.
Supporting information
CCDC reference: 217458
Key indicators
- Single-crystal X-ray study
- T = 100 K
- Mean (C-C) = 0.002 Å
- R factor = 0.042
- wR factor = 0.113
- Data-to-parameter ratio = 22.8
checkCIF results
No syntax errors found
ADDSYM reports no extra symmetry
To 15 ml tetrahydrofuran were added but-3-enyl benzoate (0.10 g., 0.56 mmol, 1 eq.), and methyl vinyl ketone (0.85 g, 11.2 mmol, 20 eq.). Hoyveda's catalyst (0.018 g, 0.028 mmol, 0.05 eq) (Garber et al., 2000) was added to the flask in 5 ml dichloromethane. The reaction mixture was stirred until complete by TLC. The reaction mixture was purified by column chromatography to obtain the title compound after removal of solvent.
Hydrogen atoms were placed in idealized positions, with C—H bond distances 0.95–0.99 Å, and thereafter treated as riding. Displacement parameters for H were assigned as Uiso = 1.2Ueq of the attached atom.
Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO and SCALEPACK; data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
Crystal data top
C20H20O4 | Z = 1 |
Mr = 324.36 | F(000) = 172 |
Triclinic, P1 | Dx = 1.270 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.829 (3) Å | Cell parameters from 2385 reflections |
b = 7.508 (2) Å | θ = 2.5–30.0° |
c = 9.460 (4) Å | µ = 0.09 mm−1 |
α = 67.424 (17)° | T = 100 K |
β = 81.663 (15)° | Plate, colorless |
γ = 71.322 (16)° | 0.42 × 0.37 × 0.07 mm |
V = 424.1 (3) Å3 | |
Data collection top
KappaCCD diffractometer (with Oxford Cryostream) | 1979 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.021 |
Graphite monochromator | θmax = 30.0°, θmin = 3.1° |
ω scans with κ offsets | h = −9→9 |
9345 measured reflections | k = −10→10 |
2480 independent reflections | l = −13→13 |
Refinement top
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)] = 0.042 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.113 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0517P)2 + 0.0772P] where P = (Fo2 + 2Fc2)/3 |
2480 reflections | (Δ/σ)max < 0.001 |
109 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
Crystal data top
C20H20O4 | γ = 71.322 (16)° |
Mr = 324.36 | V = 424.1 (3) Å3 |
Triclinic, P1 | Z = 1 |
a = 6.829 (3) Å | Mo Kα radiation |
b = 7.508 (2) Å | µ = 0.09 mm−1 |
c = 9.460 (4) Å | T = 100 K |
α = 67.424 (17)° | 0.42 × 0.37 × 0.07 mm |
β = 81.663 (15)° | |
Data collection top
KappaCCD diffractometer (with Oxford Cryostream) | 1979 reflections with I > 2σ(I) |
9345 measured reflections | Rint = 0.021 |
2480 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.113 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.30 e Å−3 |
2480 reflections | Δρmin = −0.20 e Å−3 |
109 parameters | |
Special details top
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) top | x | y | z | Uiso*/Ueq | |
O1 | 0.11730 (10) | 0.70498 (11) | 0.12298 (8) | 0.02549 (17) | |
O2 | −0.22346 (11) | 0.81072 (11) | 0.17281 (8) | 0.02958 (19) | |
C1 | 0.43531 (15) | 0.47590 (14) | 0.46947 (11) | 0.0250 (2) | |
H1 | 0.3689 | 0.3797 | 0.5361 | 0.030* | |
C2 | 0.38650 (15) | 0.56267 (15) | 0.30258 (11) | 0.0253 (2) | |
H2A | 0.4299 | 0.4536 | 0.2603 | 0.030* | |
H2B | 0.4647 | 0.6609 | 0.2465 | 0.030* | |
C3 | 0.15700 (14) | 0.66633 (15) | 0.27988 (11) | 0.0241 (2) | |
H3A | 0.0760 | 0.5787 | 0.3515 | 0.029* | |
H3B | 0.1178 | 0.7943 | 0.2987 | 0.029* | |
C4 | −0.08221 (14) | 0.77226 (14) | 0.08580 (11) | 0.0226 (2) | |
C5 | −0.10756 (14) | 0.79355 (13) | −0.07446 (11) | 0.0227 (2) | |
C6 | −0.30669 (15) | 0.86558 (15) | −0.13057 (12) | 0.0263 (2) | |
H6 | −0.4226 | 0.8959 | −0.0660 | 0.032* | |
C7 | −0.33613 (17) | 0.89324 (15) | −0.28083 (12) | 0.0291 (2) | |
H7 | −0.4718 | 0.9449 | −0.3196 | 0.035* | |
C8 | −0.16690 (17) | 0.84526 (15) | −0.37391 (12) | 0.0302 (2) | |
H8 | −0.1869 | 0.8639 | −0.4765 | 0.036* | |
C9 | 0.03194 (17) | 0.77001 (16) | −0.31778 (12) | 0.0297 (2) | |
H9 | 0.1473 | 0.7358 | −0.3816 | 0.036* | |
C10 | 0.06215 (15) | 0.74486 (15) | −0.16834 (12) | 0.0262 (2) | |
H10 | 0.1981 | 0.6946 | −0.1302 | 0.031* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0179 (3) | 0.0336 (4) | 0.0233 (3) | −0.0050 (3) | −0.0009 (2) | −0.0104 (3) |
O2 | 0.0215 (4) | 0.0377 (4) | 0.0268 (4) | −0.0053 (3) | 0.0022 (3) | −0.0124 (3) |
C1 | 0.0202 (4) | 0.0246 (4) | 0.0279 (5) | −0.0047 (3) | −0.0003 (3) | −0.0085 (4) |
C2 | 0.0202 (4) | 0.0283 (5) | 0.0269 (5) | −0.0061 (4) | −0.0005 (3) | −0.0101 (4) |
C3 | 0.0208 (4) | 0.0276 (5) | 0.0224 (5) | −0.0053 (3) | −0.0011 (3) | −0.0087 (4) |
C4 | 0.0183 (4) | 0.0222 (4) | 0.0256 (5) | −0.0054 (3) | −0.0003 (3) | −0.0072 (3) |
C5 | 0.0218 (4) | 0.0202 (4) | 0.0247 (5) | −0.0053 (3) | −0.0007 (3) | −0.0071 (3) |
C6 | 0.0220 (5) | 0.0257 (5) | 0.0304 (5) | −0.0044 (4) | −0.0013 (4) | −0.0111 (4) |
C7 | 0.0277 (5) | 0.0271 (5) | 0.0328 (5) | −0.0053 (4) | −0.0072 (4) | −0.0109 (4) |
C8 | 0.0381 (6) | 0.0270 (5) | 0.0262 (5) | −0.0093 (4) | −0.0037 (4) | −0.0094 (4) |
C9 | 0.0305 (5) | 0.0300 (5) | 0.0280 (5) | −0.0073 (4) | 0.0037 (4) | −0.0125 (4) |
C10 | 0.0226 (5) | 0.0254 (5) | 0.0280 (5) | −0.0048 (4) | 0.0003 (4) | −0.0090 (4) |
Geometric parameters (Å, º) top
O1—C4 | 1.3405 (13) | C5—C6 | 1.3933 (14) |
O1—C3 | 1.4479 (13) | C5—C10 | 1.3946 (14) |
O2—C4 | 1.2104 (12) | C6—C7 | 1.3905 (15) |
C1—C1i | 1.326 (2) | C6—H6 | 0.95 |
C1—C2 | 1.5006 (15) | C7—C8 | 1.3865 (16) |
C1—H1 | 0.95 | C7—H7 | 0.95 |
C2—C3 | 1.5153 (15) | C8—C9 | 1.3901 (16) |
C2—H2A | 0.99 | C8—H8 | 0.95 |
C2—H2B | 0.99 | C9—C10 | 1.3898 (15) |
C3—H3A | 0.99 | C9—H9 | 0.95 |
C3—H3B | 0.99 | C10—H10 | 0.95 |
C4—C5 | 1.4920 (15) | | |
| | | |
C4—O1—C3 | 115.89 (7) | C6—C5—C10 | 119.82 (10) |
C1i—C1—C2 | 124.60 (12) | C6—C5—C4 | 118.50 (9) |
C1i—C1—H1 | 117.7 | C10—C5—C4 | 121.68 (9) |
C2—C1—H1 | 117.7 | C7—C6—C5 | 120.16 (9) |
C1—C2—C3 | 110.66 (8) | C7—C6—H6 | 119.9 |
C1—C2—H2A | 109.5 | C5—C6—H6 | 119.9 |
C3—C2—H2A | 109.5 | C8—C7—C6 | 119.80 (10) |
C1—C2—H2B | 109.5 | C8—C7—H7 | 120.1 |
C3—C2—H2B | 109.5 | C6—C7—H7 | 120.1 |
H2A—C2—H2B | 108.1 | C7—C8—C9 | 120.31 (10) |
O1—C3—C2 | 106.81 (8) | C7—C8—H8 | 119.8 |
O1—C3—H3A | 110.4 | C9—C8—H8 | 119.8 |
C2—C3—H3A | 110.4 | C10—C9—C8 | 120.04 (10) |
O1—C3—H3B | 110.4 | C10—C9—H9 | 120.0 |
C2—C3—H3B | 110.4 | C8—C9—H9 | 120.0 |
H3A—C3—H3B | 108.6 | C9—C10—C5 | 119.85 (10) |
O2—C4—O1 | 123.51 (9) | C9—C10—H10 | 120.1 |
O2—C4—C5 | 124.63 (9) | C5—C10—H10 | 120.1 |
O1—C4—C5 | 111.86 (8) | | |
| | | |
C1i—C1—C2—C3 | −121.21 (14) | C10—C5—C6—C7 | −1.46 (14) |
C4—O1—C3—C2 | 171.48 (8) | C4—C5—C6—C7 | 178.05 (8) |
C1—C2—C3—O1 | −167.53 (7) | C5—C6—C7—C8 | 1.24 (15) |
C3—O1—C4—O2 | 4.11 (14) | C6—C7—C8—C9 | −0.11 (15) |
C3—O1—C4—C5 | −175.94 (7) | C7—C8—C9—C10 | −0.80 (16) |
O2—C4—C5—C6 | 1.05 (14) | C8—C9—C10—C5 | 0.58 (15) |
O1—C4—C5—C6 | −178.90 (8) | C6—C5—C10—C9 | 0.54 (15) |
O2—C4—C5—C10 | −179.45 (9) | C4—C5—C10—C9 | −178.95 (9) |
O1—C4—C5—C10 | 0.60 (13) | | |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Experimental details
Crystal data |
Chemical formula | C20H20O4 |
Mr | 324.36 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 100 |
a, b, c (Å) | 6.829 (3), 7.508 (2), 9.460 (4) |
α, β, γ (°) | 67.424 (17), 81.663 (15), 71.322 (16) |
V (Å3) | 424.1 (3) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.42 × 0.37 × 0.07 |
|
Data collection |
Diffractometer | KappaCCD diffractometer (with Oxford Cryostream) |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9345, 2480, 1979 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.703 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.113, 1.05 |
No. of reflections | 2480 |
No. of parameters | 109 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.30, −0.20 |
Selected geometric parameters (Å, º) topO1—C4 | 1.3405 (13) | O2—C4 | 1.2104 (12) |
O1—C3 | 1.4479 (13) | C1—C1i | 1.326 (2) |
| | | |
C4—O1—C3 | 115.89 (7) | C1i—C1—C2 | 124.60 (12) |
| | | |
C1i—C1—C2—C3 | −121.21 (14) | C3—O1—C4—C5 | −175.94 (7) |
C4—O1—C3—C2 | 171.48 (8) | O1—C4—C5—C10 | 0.60 (13) |
C1—C2—C3—O1 | −167.53 (7) | | |
Symmetry code: (i) −x+1, −y+1, −z+1. |
During an attempted cross metathesis reaction, the title compound, (I), was produced in an interesting side reaction. Such cross metathesis reactions, which tend to be unpredictable, occur between two olefins in the presence of a Ru catalyst known as Hoyveda's catalyst (Garber et al., 2000). In the reaction, an olefin first reacts with the Ru catalyst, and then the highly reactive intermediate reacts with a different olefin. In this case, the second step was reaction of another molecule of the first olefin, but-3-enyl benzoate, to form the title dimer. The crystal structure determination was carried out in order to identify the unexpected product.
The molecule, which lies on a crystallographic inversion center, is illustrated in Fig. 1. The central 3-hexene moiety is nonplanar, with torsion angle C3—C2—C1—C1i [symmetry code: (i) = 1 − x, 1 − y, 1 − z] of −121.21 (14)°, yielding the dihedral angles given in the abstract.
The title compound has been previously reported as an intermediate in the synthesis of the corresponding 3,4-diol (Torneiro & Still, 1997).