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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 8| August 2009| Page o1967
doi:10.1107/S1600536809028256

(S)-6-{[(S)-2,2-Di­methyl-1,3-dioxolan-4-yl]meth­yl}-5,5-di­fluoro-5,6-di­hydro-2H-pyran-2-one

Zengsheng Yin,a* Xiangjun Deng,a Rongxing Yao,a Hongqi Lia and Pinqiao Zhaob

aKey Laboratory of Science & Technology of Eco-Textiles, Ministry of Education, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, People's Republic of China, and bKey Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, Shanghai 200032, People's Republic of China
*Correspondence e-mail: zsyin@mail.dhu.edu.cn

(Received 29 June 2009; accepted 17 July 2009; online 25 July 2009)

The title compound, C11H14F2O4, is a γ,γ-gem-difluorinated α,β-unsaturated δ-lactone. The dioxolane five-membered ring and the lactone ring adopt half-chair conformations. There are two inter­molecular C—H⋯O inter­actions involving the carbonyl group as an acceptor which stabilize the crystal structure.

Related literature

For related synthetic procedures, see: Borjesson & Welch (1992[Borjesson, L. & Welch, C. H. (1992). Tetrahedron, 48, 6325-6334.]); Dardonville & Gilbert (2003[Dardonville, C. & Gilbert, I. H. (2003). Org. Biomol. Chem. 1, 552-559.]); Gaunt et al. (2003[Gaunt, M. J., Jessiman, A. S., Orsini, P., Tanner, H. R., Hook, D. F. & Ley, S. V. (2003). Org. Lett. 5, 4819-4822.]); Saito et al. (1992[Saito, S., Ishikawa, T., Kuroda, A. & Moriwake, T. (1992). Tetrahedron, 48, 4067-4086.]); You et al. (2006[You, Z. W., Jiang, Z. X., Wang, B. L. & Qing, F. L. (2006). J. Org. Chem. 71, 7261-7267.]).

[Scheme 1]

Experimental

Crystal data

  • C11H14F2O4

  • Mr = 248.22

  • Orthorhombic, P 21 21 21

  • a = 5.8003 (8) Å

  • b = 7.8135 (11) Å

  • c = 25.977 (4) Å

  • V = 1177.3 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 293 K

  • 0.51 × 0.48 × 0.26 mm
Data collection

  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.761, Tmax = 1.000 (expected range = 0.736–0.968)

  • 6682 measured reflections

  • 1455 independent reflections

  • 1261 reflections with I > 2σ(I)

  • Rint = 0.131
Refinement

  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.134

  • S = 1.00

  • 1455 reflections

  • 173 parameters

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

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.32 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C8—H8⋯O1i 0.95 (3) 2.66 (3) 3.578 (4) 161 (2)
C6—H6⋯O1ii 0.96 (3) 2.44 (3) 3.318 (4) 151 (2)
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+2]; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+2].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809028256/gk2220sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809028256/gk2220Isup2.hkl

checkCIF report


Comment top

α,β-Unsaturated δ-lactone is a common structural unit of natural products with bioactivity. The structure-activity relationship (SAR) reveals that the unsaturated lactone often plays a key role in the bioactivity. The reason may be that the unsaturated lactone is an excellent potential Michael acceptor for natural nucleophiles such as the amino-acid residues. The title compound is an γ,γ-gem-difluorinated α,β-unsaturated δ-lactone, a better Michael acceptor for the electron-withdrawing of the difluoromethylene group. So it is a useful intermediate for synthesis of the fluorine-containing analogues of natural product with potential bioactivity. The title compound was prepared from L-malic acid according to the method developed by our group (You et al., 2006) and other groups (Borjesson et al., 1992; Dardonville et al., 2003; Gaunt et al., 2003; Saito et al., 1992). Our interest is focused on the changes caused by introducing difluoromethylene group into the lactone ring. Here we report the crystal structure of the title compound.

The absolute configuration of the title compound was determined by the known chirality of the C8 derived from the starting material, L-malic acid. All bond lengths and angles in the lactone ring are within normal ranges. The dioxolane five-membered ring and the lactone ring both adopt a half-chair conformation. Intermolecular interactions C6—H6···O1 and C8—H6···O1 arrange the moleculesd in a head-to-head fashion (see Fig. 2).

Related literature top

For related synthetic procedures, see: Borjesson & Welch (1992); Dardonville & Gilbert (2003); Gaunt et al. (2003); Saito et al. (1992); You et al. (2006).

Experimental top

For the reaction scheme see Figure 3. To a solution of (Z)-6-((S)-2,2-dimethyl-1,3-dioxolan-4-yl)-4,4- difluorohex-2-ene-1,5-diol in CH2Cl2 was added bis-acetoxyiodobenzene (3 eq) and 2,2,6,6-tetramethyl piperidinooxy (0.1 eq) at room temperature. After stirring for 3 h, the reaction was quenched with saturated solution of Na2S2O3 and extracted with CH2Cl2. The combined organic extracts were washed with saturated solution of NaHCO3, NH4Cl, brine, dried over anhydrous MgSO4, filtered and concentrated. The residue was purified by flash chromatography on silica gel (petroleum ether / ethyl acetate = 10:1) to afford the title compound. Crystals suitable for X-ray structural analysis were obtained by slow evaporation of a solution in actone and petroleum ether (1:1, v/v).

Refinement top

All H atoms could be located in a difference Fourier map. The H atoms from the piran-2-one fragment and the methine H8 atom were fully refined. The remaining H atoms were placed in calculated positions (C-H = 0.97-0.98 Å) and refined using a riding model approximation with Uiso(H) = 1.2Ueq(C) or Uiso(H) = 1.5Ueq(methyl C). Friedel pairs were merged as no significant anomalous scattering effects were observed. The absolute configuration was related to a known chirality (S) of the dioxolane C8 atom. The high Rint value results from a poor quality of the measured crystal.

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: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecule of the title compound. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along a axis. Dashed lines indicate the hydrogen bond interactions.
[Figure 3] Fig. 3. The scheme of synthesis of the title compound.
(S)-6-{[(S)-2,2-Dimethyl-1,3-dioxolan-4-yl]methyl}-5,5- difluoro-5,6-dihydro-2H-pyran-2-one top
Crystal data top
C11H14F2O4Dx = 1.400 Mg m−3
Mr = 248.22Melting point: 351 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 2723 reflections
a = 5.8003 (8) Åθ = 2.7–27.7°
b = 7.8135 (11) ŵ = 0.13 mm−1
c = 25.977 (4) ÅT = 293 K
V = 1177.3 (3) Å3Prismatic, colorless
Z = 40.51 × 0.48 × 0.26 mm
F(000) = 520
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1455 independent reflections
Radiation source: fine-focus sealed tube1261 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.131
Detector resolution: 0 pixels mm-1θmax = 26.5°, θmin = 1.6°
ϕ and ω scansh = −7→7
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		k = −9→9
Tmin = 0.761, Tmax = 1.000l = −22→32
6682 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.054H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.134 w = 1/[σ2(Fo2) + (0.0757P)2 + 0.0067P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.001
1455 reflectionsΔρmax = 0.25 e Å−3
173 parametersΔρmin = −0.32 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.024 (5)
Crystal data top
C11H14F2O4V = 1177.3 (3) Å3
Mr = 248.22Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 5.8003 (8) ŵ = 0.13 mm−1
b = 7.8135 (11) ÅT = 293 K
c = 25.977 (4) Å0.51 × 0.48 × 0.26 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		1455 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		1261 reflections with I > 2σ(I)
Tmin = 0.761, Tmax = 1.000Rint = 0.131
6682 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0540 restraints
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.25 e Å−3
1455 reflectionsΔρmin = −0.32 e Å−3
173 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
xyzUiso*/Ueq
O10.3246 (5)0.3829 (4)1.04388 (8)0.0741 (7)
O20.3476 (3)0.4190 (2)0.96034 (7)0.0476 (5)
O30.3431 (4)0.1554 (3)0.85332 (9)0.0639 (7)
O40.1373 (4)0.1699 (3)0.78051 (8)0.0644 (6)
F10.5404 (4)0.7375 (2)0.92182 (8)0.0666 (6)
F20.8095 (3)0.5889 (3)0.88536 (7)0.0720 (6)
C10.4418 (5)0.4245 (4)1.00830 (11)0.0517 (7)
C20.6747 (6)0.4915 (4)1.01335 (13)0.0570 (8)
C30.7764 (5)0.5731 (4)0.97527 (13)0.0559 (8)
C50.6553 (4)0.5857 (4)0.92469 (11)0.0473 (6)
C60.4949 (4)0.4373 (3)0.91582 (10)0.0393 (6)
C70.3425 (5)0.4559 (3)0.86946 (11)0.0436 (6)
H7A0.43760.47610.83940.052*
H7B0.24330.55460.87410.052*
C80.1945 (5)0.2985 (4)0.86032 (11)0.0468 (6)
C90.0516 (6)0.3041 (4)0.81085 (13)0.0612 (8)
H9A−0.11070.28720.81830.073*
H9B0.07060.41310.79350.073*
C100.2494 (5)0.0526 (4)0.81349 (11)0.0529 (7)
C110.0790 (8)−0.0735 (4)0.83574 (15)0.0712 (9)
H11A0.0221−0.14640.80880.107*
H11B−0.0473−0.01240.85100.107*
H11C0.1539−0.14180.86150.107*
C120.4412 (7)−0.0334 (6)0.7860 (2)0.0917 (14)
H12A0.54560.05120.77280.137*
H12B0.3803−0.09980.75810.137*
H12C0.5218−0.10730.80940.137*
H20.758 (6)0.483 (5)1.0503 (15)0.070 (10)*
H30.936 (7)0.614 (5)0.9775 (14)0.070 (10)*
H60.588 (4)0.335 (3)0.9143 (11)0.038 (7)*
H80.084 (5)0.278 (3)0.8868 (12)0.039 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0934 (15)0.0921 (17)0.0369 (11)−0.0240 (15)0.0040 (11)0.0066 (13)
O20.0503 (9)0.0605 (11)0.0319 (9)−0.0088 (9)−0.0024 (7)0.0022 (9)
O30.0785 (13)0.0511 (11)0.0622 (14)0.0125 (11)−0.0381 (12)−0.0168 (12)
O40.0925 (15)0.0675 (13)0.0331 (10)0.0026 (13)−0.0193 (11)0.0025 (11)
F10.0884 (12)0.0420 (8)0.0694 (13)0.0005 (8)−0.0035 (10)−0.0024 (10)
F20.0613 (10)0.0915 (13)0.0633 (12)−0.0178 (10)0.0215 (9)−0.0051 (11)
C10.0662 (15)0.0513 (15)0.0377 (14)−0.0059 (14)−0.0075 (13)0.0004 (14)
C20.0676 (17)0.0553 (15)0.0481 (16)−0.0037 (15)−0.0169 (15)−0.0088 (15)
C30.0468 (14)0.0617 (17)0.0591 (18)−0.0077 (13)−0.0064 (13)−0.0158 (16)
C50.0487 (12)0.0468 (14)0.0465 (15)−0.0032 (12)0.0073 (12)−0.0055 (13)
C60.0424 (12)0.0418 (13)0.0336 (13)0.0014 (10)0.0024 (10)−0.0028 (12)
C70.0532 (13)0.0448 (13)0.0328 (12)0.0013 (11)−0.0011 (11)0.0044 (11)
C80.0569 (14)0.0484 (14)0.0352 (13)0.0006 (12)−0.0093 (13)0.0018 (13)
C90.0747 (17)0.0619 (18)0.0470 (17)0.0064 (15)−0.0250 (16)−0.0014 (16)
C100.0641 (15)0.0534 (16)0.0414 (15)0.0008 (13)−0.0142 (13)−0.0082 (14)
C110.096 (2)0.0593 (19)0.058 (2)−0.0092 (18)−0.0136 (18)−0.0016 (18)
C120.084 (2)0.094 (3)0.098 (3)0.008 (2)0.006 (2)−0.031 (3)
Geometric parameters (Å, º) top
O1—C11.193 (4)C6—H60.96 (3)
O2—C11.361 (3)C7—C81.518 (4)
O2—C61.445 (3)C7—H7A0.9700
O3—C101.418 (3)C7—H7B0.9700
O3—C81.424 (4)C8—C91.530 (4)
O4—C91.402 (4)C8—H80.95 (3)
O4—C101.414 (4)C9—H9A0.9700
F1—C51.362 (3)C9—H9B0.9700
F2—C51.358 (3)C10—C121.482 (5)
C1—C21.455 (5)C10—C111.511 (5)
C2—C31.316 (5)C11—H11A0.9600
C2—H21.08 (4)C11—H11B0.9600
C3—C51.493 (4)C11—H11C0.9600
C3—H30.98 (4)C12—H12A0.9600
C5—C61.505 (3)C12—H12B0.9600
C6—C71.501 (4)C12—H12C0.9600
C1—O2—C6119.5 (2)O3—C8—C7108.3 (2)
C10—O3—C8107.82 (19)O3—C8—C9104.1 (2)
C9—O4—C10107.9 (2)C7—C8—C9114.5 (2)
O1—C1—O2118.2 (3)O3—C8—H8111.6 (17)
O1—C1—C2123.9 (3)C7—C8—H8113.8 (17)
O2—C1—C2117.8 (3)C9—C8—H8104.2 (17)
C3—C2—C1121.5 (3)O4—C9—C8105.0 (2)
C3—C2—H2120 (2)O4—C9—H9A110.7
C1—C2—H2118 (2)C8—C9—H9A110.7
C2—C3—C5118.9 (3)O4—C9—H9B110.7
C2—C3—H3122 (2)C8—C9—H9B110.7
C5—C3—H3118 (2)H9A—C9—H9B108.8
F2—C5—F1105.4 (2)O4—C10—O3104.5 (2)
F2—C5—C3110.7 (2)O4—C10—C12110.3 (3)
F1—C5—C3109.6 (3)O3—C10—C12108.7 (3)
F2—C5—C6107.8 (2)O4—C10—C11110.7 (3)
F1—C5—C6111.1 (2)O3—C10—C11109.9 (3)
C3—C5—C6112.0 (3)C12—C10—C11112.3 (3)
O2—C6—C7107.65 (18)C10—C11—H11A109.5
O2—C6—C5108.6 (2)C10—C11—H11B109.5
C7—C6—C5114.4 (2)H11A—C11—H11B109.5
O2—C6—H6106.4 (16)C10—C11—H11C109.5
C7—C6—H6112.1 (17)H11A—C11—H11C109.5
C5—C6—H6107.4 (16)H11B—C11—H11C109.5
C6—C7—C8112.3 (2)C10—C12—H12A109.5
C6—C7—H7A109.1C10—C12—H12B109.5
C8—C7—H7A109.1H12A—C12—H12B109.5
C6—C7—H7B109.1C10—C12—H12C109.5
C8—C7—H7B109.1H12A—C12—H12C109.5
H7A—C7—H7B107.9H12B—C12—H12C109.5
C6—O2—C1—O1−168.5 (3)O2—C6—C7—C8−62.7 (3)
C6—O2—C1—C215.5 (4)C5—C6—C7—C8176.5 (2)
O1—C1—C2—C3−163.5 (3)C10—O3—C8—C7−140.1 (2)
O2—C1—C2—C312.3 (5)C10—O3—C8—C9−17.9 (3)
C1—C2—C3—C5−4.4 (5)C6—C7—C8—O3−59.2 (3)
C2—C3—C5—F2−148.5 (3)C6—C7—C8—C9−174.8 (2)
C2—C3—C5—F195.6 (3)C10—O4—C9—C821.3 (3)
C2—C3—C5—C6−28.1 (4)O3—C8—C9—O4−2.0 (3)
C1—O2—C6—C7−170.7 (2)C7—C8—C9—O4116.0 (3)
C1—O2—C6—C5−46.3 (3)C9—O4—C10—O3−32.7 (3)
F2—C5—C6—O2173.1 (2)C9—O4—C10—C12−149.4 (3)
F1—C5—C6—O2−71.9 (3)C9—O4—C10—C1185.6 (3)
C3—C5—C6—O251.1 (3)C8—O3—C10—O431.3 (3)
F2—C5—C6—C7−66.6 (3)C8—O3—C10—C12149.1 (3)
F1—C5—C6—C748.3 (3)C8—O3—C10—C11−87.6 (3)
C3—C5—C6—C7171.3 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O1i0.95 (3)2.66 (3)3.578 (4)161 (2)
C6—H6···O1ii0.96 (3)2.44 (3)3.318 (4)151 (2)
Symmetry codes: (i) x−1/2, −y+1/2, −z+2; (ii) x+1/2, −y+1/2, −z+2.

Experimental details

Crystal data
Chemical formulaC11H14F2O4
Mr248.22
Crystal system, space groupOrthorhombic, P212121
Temperature (K)293
a, b, c (Å)5.8003 (8), 7.8135 (11), 25.977 (4)
V (Å3)1177.3 (3)
Z4
Radiation typeMo Kα
µ (mm−1)0.13
Crystal size (mm)0.51 × 0.48 × 0.26
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.761, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		6682, 1455, 1261
Rint0.131
(sin θ/λ)max (Å−1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.134, 1.00
No. of reflections1455
No. of parameters173
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.25, −0.32

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O1i0.95 (3)2.66 (3)3.578 (4)161 (2)
C6—H6···O1ii0.96 (3)2.44 (3)3.318 (4)151 (2)
Symmetry codes: (i) x−1/2, −y+1/2, −z+2; (ii) x+1/2, −y+1/2, −z+2.
 

Acknowledgements

Financial support of this project by the Program for Changjiang Scholars and Innovative Research Teams in Universities (No. IRT0526) is acknowledged.

References

First citationBorjesson, L. & Welch, C. H. (1992). Tetrahedron, 48, 6325–6334.  CrossRef Web of Science Google Scholar
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ISSN: 2056-9890
Volume 65| Part 8| August 2009| Page o1967
doi:10.1107/S1600536809028256
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