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

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ISSN: 2056-9890

Methyl 2,2-dimeth­­oxy-8-oxo-1-oxa­spiro­[4.5]deca-6,9-diene-3-carboxyl­ate

aSchool of Chemistry and Chemical Engineering, Southeast University, Southeast University Road 2, Jiangning District, 211189 Nanjing, People's Republic of China
*Correspondence e-mail: lou@seu.edu.cn

(Received 2 December 2011; accepted 18 March 2012; online 24 March 2012)

In the title mol­ecule, C13H16O6, the cyclo­hexa-1,4-diene ring adopts a flat boat conformation (r.m.s. deviation from planarity = 0.060 Å) and the five-membered tetra­hydro­furan ring adopts an envelope conformation with the carboxyl group-substituted C atom as the flap. The dihedral angle at the spiro junction is 89.1 (1)°. In the crystal, mol­ecules are linked through weak C—H⋯O and van der Waals inter­actions.

Related literature

For background to bioactive tetronic acid derivatives, see: Fischer et al. (1993[Fischer, R. M., Bretschneider, T. S. & Kruger, B.-W. (1993). US Patent No. 5 262 383.]); Bayer Aktiengesellschaft (1995)[Bayer Aktiengesellschaft (1995). WO Patent No. 9 504 719A1.].

[Scheme 1]

Experimental

Crystal data
  • C13H16O6

  • Mr = 268.26

  • Monoclinic, P 21 /c

  • a = 6.5324 (7) Å

  • b = 11.7519 (12) Å

  • c = 17.4204 (18) Å

  • β = 97.723 (2)°

  • V = 1325.2 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 298 K

  • 0.31 × 0.26 × 0.21 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.958, Tmax = 0.978

  • 7015 measured reflections

  • 2588 independent reflections

  • 2140 reflections with I > 2σ(I)

  • Rint = 0.020

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.140

  • S = 1.05

  • 2588 reflections

  • 175 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C13—H13A⋯O3i 0.96 2.60 3.269 (3) 127
Symmetry code: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). 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


Comment top

The chemistry of tetronic acid (tetrahydrofuran-2,4-dione) compounds has received increasing attention in recent years due to their high biological activity as herbicides and insecticides (Fischer et al., 1993). The company Bayer AG has developed three tetronic acid pesticides, spirodiclofen, spiromesifen, and spirotetramat (Bayer Aktiengesellschaft, 1995), which are now in wide use in crop protection. As part of our studies in this area, we describe here the structure of the title compound (Scheme 1).

The title molecule (Fig. 1) contains one six-membered and one five-membered ring connected with a spiro-carbon C4. All bond lengths in this spiro system adopt normal values, e.g. the double bonds C2C3, C5C6, and C1O1 with values of 1.320 (3) Å, 1.322 (3) Å, and 1.219 (2) Å, respectively. The cyclohexadienone unit is slightly bent to a flat boat conformation with atoms C2, C3, C5, C6 being practically coplanar and C1, C4, and O1 by 0.087 (3), 0.0163 (3), and 0.191 (5) Å, respectively, off from the plane of the former atoms. The five-membered tetrahydrofuran ring adopts an envelope conformation with C8 by 0.558 (3) Å out of the least-squares plane through O2, C4, C7, and C9 (their r.m.s. deviation from l.s. plane is 0.017 Å). In the crystal (Fig. 2), the molecules are linked through weak van der Waals and C-H···O interactions.

Related literature top

For background to bioactive tetronic acid derivatives, see: Fischer et al. (1993); Bayer Aktiengesellschaft (1995).

Experimental top

The starting material and all intermediates are known from literature and are obtained by standard procedures. The title compound was synthesized starting with 4-hydroxybenzaldehyde according to Fig. 3. using standard procedures for the intermediates 2 through 5. Then, to a solution of 5 (800 mg, 3.36 mmol) in MeOH (12 ml) was added a solution of PhI(OAc)2 (1.6 g, 4.97 mmol) in CH2Cl2 (7 ml) at room temperature. The mixture was stirred for 30 min. The solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography (EtOAc: PE = 1:3) to afford 6 (648.1 mg, 72% yield). 1H NMR (400 MHz, CDCl3) δ 2.28 (dd, J =9.2 Hz, 13.6 Hz, 1H), 2.72 (dd, J = 8.0 Hz, 13.6 Hz, 1H), 3.38 (s, 3H), 3.46 (s, 3H), 3.78 (s, 3H), 6.15–6.20 (m, 2H), 6.89–6.92 (m, 1H), 7.07–7.10 (m, 1H). 13C NMR (100 MHz, CDCl3) δ 36.9, 48.4, 49.9, 51.1, 52.4, 75.8, 122.2, 127.6, 148.2, 149.2, 169.5, 185.0.

Refinement top

All H atoms were placed in calculated positions with C—H = 0.93–0.98Å and were included in the final cycle of refinement in the riding mode with Uiso(H) = 1.2 or 1.5Ueq(C).

Structure description top

The chemistry of tetronic acid (tetrahydrofuran-2,4-dione) compounds has received increasing attention in recent years due to their high biological activity as herbicides and insecticides (Fischer et al., 1993). The company Bayer AG has developed three tetronic acid pesticides, spirodiclofen, spiromesifen, and spirotetramat (Bayer Aktiengesellschaft, 1995), which are now in wide use in crop protection. As part of our studies in this area, we describe here the structure of the title compound (Scheme 1).

The title molecule (Fig. 1) contains one six-membered and one five-membered ring connected with a spiro-carbon C4. All bond lengths in this spiro system adopt normal values, e.g. the double bonds C2C3, C5C6, and C1O1 with values of 1.320 (3) Å, 1.322 (3) Å, and 1.219 (2) Å, respectively. The cyclohexadienone unit is slightly bent to a flat boat conformation with atoms C2, C3, C5, C6 being practically coplanar and C1, C4, and O1 by 0.087 (3), 0.0163 (3), and 0.191 (5) Å, respectively, off from the plane of the former atoms. The five-membered tetrahydrofuran ring adopts an envelope conformation with C8 by 0.558 (3) Å out of the least-squares plane through O2, C4, C7, and C9 (their r.m.s. deviation from l.s. plane is 0.017 Å). In the crystal (Fig. 2), the molecules are linked through weak van der Waals and C-H···O interactions.

For background to bioactive tetronic acid derivatives, see: Fischer et al. (1993); Bayer Aktiengesellschaft (1995).

Computing details top

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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids were drawn at the 30% probability level.
[Figure 2] Fig. 2. Packing diagram of the structure viewed down the a-axis.
[Figure 3] Fig. 3. Synthetic route for the title compound.
Methyl 2,2-dimethoxy-8-oxo-1-oxaspiro[4.5]deca-6,9-diene-3-carboxylate top
Crystal data top
C13H16O6F(000) = 568
Mr = 268.26Dx = 1.345 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2543 reflections
a = 6.5324 (7) Åθ = 5.9–49.9°
b = 11.7519 (12) ŵ = 0.11 mm1
c = 17.4204 (18) ÅT = 298 K
β = 97.723 (2)°Prismatic, colorless
V = 1325.2 (2) Å30.31 × 0.26 × 0.21 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer
2588 independent reflections
Radiation source: fine-focus sealed tube2140 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
φ and ω scansθmax = 26.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 78
Tmin = 0.958, Tmax = 0.978k = 1414
7015 measured reflectionsl = 1321
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0751P)2 + 0.297P]
where P = (Fo2 + 2Fc2)/3
2588 reflections(Δ/σ)max < 0.001
175 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C13H16O6V = 1325.2 (2) Å3
Mr = 268.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.5324 (7) ŵ = 0.11 mm1
b = 11.7519 (12) ÅT = 298 K
c = 17.4204 (18) Å0.31 × 0.26 × 0.21 mm
β = 97.723 (2)°
Data collection top
Bruker SMART CCD
diffractometer
2588 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
2140 reflections with I > 2σ(I)
Tmin = 0.958, Tmax = 0.978Rint = 0.020
7015 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.140H-atom parameters constrained
S = 1.05Δρmax = 0.29 e Å3
2588 reflectionsΔρmin = 0.22 e Å3
175 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
O10.2524 (3)0.60788 (16)0.03288 (8)0.0876 (5)
O20.0228 (2)0.64745 (11)0.26381 (7)0.0560 (4)
O30.5107 (3)0.39189 (16)0.31643 (8)0.0826 (5)
O40.34081 (19)0.39820 (12)0.41846 (7)0.0571 (4)
O50.08806 (19)0.62430 (12)0.39416 (7)0.0567 (4)
O60.35585 (19)0.64129 (11)0.32927 (7)0.0546 (4)
C10.1786 (3)0.60713 (17)0.03521 (11)0.0601 (5)
C20.0197 (3)0.66200 (19)0.06170 (12)0.0665 (6)
H20.08460.70400.02670.080*
C30.1080 (3)0.65306 (19)0.13416 (12)0.0639 (6)
H30.23020.69270.14910.077*
C40.0216 (3)0.58253 (16)0.19334 (10)0.0510 (4)
C50.1957 (3)0.54671 (16)0.16723 (11)0.0553 (5)
H50.27220.51700.20390.066*
C60.2852 (3)0.55504 (17)0.09477 (12)0.0601 (5)
H60.41860.52720.08150.072*
C70.1620 (3)0.47845 (17)0.21615 (10)0.0584 (5)
H7A0.10320.40960.19160.070*
H7B0.29890.48990.20180.070*
C80.1695 (3)0.47217 (14)0.30329 (9)0.0460 (4)
H80.04630.43270.31600.055*
C90.1579 (2)0.59822 (14)0.32513 (9)0.0440 (4)
C100.3594 (3)0.41569 (15)0.34472 (10)0.0490 (4)
C110.5178 (3)0.35071 (19)0.46569 (12)0.0659 (6)
H11A0.53720.27340.45030.099*
H11B0.49610.35250.51910.099*
H11C0.63830.39450.45920.099*
C120.1168 (4)0.5942 (3)0.40212 (17)0.0983 (10)
H12A0.20910.62680.36040.147*
H12B0.15060.62240.45060.147*
H12C0.13040.51290.40080.147*
C130.3702 (4)0.76269 (19)0.33775 (14)0.0778 (7)
H13A0.30630.79850.29110.117*
H13B0.51300.78460.34750.117*
H13C0.30110.78610.38040.117*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0973 (12)0.1070 (13)0.0497 (9)0.0063 (10)0.0219 (8)0.0074 (8)
O20.0571 (7)0.0555 (7)0.0502 (7)0.0126 (6)0.0116 (6)0.0035 (5)
O30.0771 (10)0.1179 (14)0.0537 (9)0.0494 (10)0.0115 (7)0.0034 (8)
O40.0570 (8)0.0695 (9)0.0441 (7)0.0098 (6)0.0041 (6)0.0112 (6)
O50.0510 (7)0.0703 (8)0.0485 (7)0.0051 (6)0.0056 (6)0.0117 (6)
O60.0456 (7)0.0566 (8)0.0596 (8)0.0074 (5)0.0004 (6)0.0070 (6)
C10.0633 (12)0.0596 (11)0.0518 (11)0.0056 (9)0.0125 (9)0.0026 (9)
C20.0652 (12)0.0766 (14)0.0554 (11)0.0081 (10)0.0006 (9)0.0161 (10)
C30.0510 (11)0.0787 (14)0.0582 (12)0.0127 (9)0.0067 (9)0.0101 (10)
C40.0487 (10)0.0578 (11)0.0431 (9)0.0014 (8)0.0061 (7)0.0020 (7)
C50.0511 (10)0.0576 (11)0.0547 (11)0.0061 (8)0.0021 (8)0.0050 (8)
C60.0509 (10)0.0617 (11)0.0622 (12)0.0066 (9)0.0130 (9)0.0016 (9)
C70.0630 (11)0.0667 (12)0.0420 (9)0.0149 (9)0.0059 (8)0.0057 (8)
C80.0452 (9)0.0484 (10)0.0430 (9)0.0024 (7)0.0012 (7)0.0013 (7)
C90.0387 (8)0.0505 (9)0.0413 (9)0.0014 (7)0.0001 (7)0.0002 (7)
C100.0560 (10)0.0491 (9)0.0412 (9)0.0090 (8)0.0039 (8)0.0024 (7)
C110.0665 (13)0.0759 (14)0.0525 (11)0.0154 (10)0.0029 (9)0.0168 (10)
C120.0590 (14)0.152 (3)0.0895 (18)0.0069 (15)0.0299 (13)0.0282 (17)
C130.0921 (16)0.0582 (12)0.0756 (14)0.0239 (11)0.0158 (12)0.0146 (11)
Geometric parameters (Å, º) top
O1—C11.219 (2)C5—C61.321 (3)
O2—C91.4148 (19)C5—H50.9300
O2—C41.444 (2)C6—H60.9300
O3—C101.195 (2)C7—C81.514 (2)
O4—C101.323 (2)C7—H7A0.9700
O4—C111.439 (2)C7—H7B0.9700
O5—C91.377 (2)C8—C101.503 (2)
O5—C121.409 (3)C8—C91.534 (2)
O6—C91.381 (2)C8—H80.9800
O6—C131.436 (3)C11—H11A0.9600
C1—C61.460 (3)C11—H11B0.9600
C1—C21.465 (3)C11—H11C0.9600
C2—C31.320 (3)C12—H12A0.9600
C2—H20.9300C12—H12B0.9600
C3—C41.492 (3)C12—H12C0.9600
C3—H30.9300C13—H13A0.9600
C4—C51.492 (2)C13—H13B0.9600
C4—C71.549 (3)C13—H13C0.9600
C9—O2—C4110.94 (13)C10—C8—C9111.85 (14)
C10—O4—C11116.36 (15)C7—C8—C9101.87 (14)
C9—O5—C12117.44 (16)C10—C8—H8109.4
C9—O6—C13114.67 (16)C7—C8—H8109.4
O1—C1—C6122.06 (19)C9—C8—H8109.4
O1—C1—C2121.4 (2)O5—C9—O6106.90 (13)
C6—C1—C2116.54 (16)O5—C9—O2108.78 (13)
C3—C2—C1121.39 (19)O6—C9—O2111.98 (14)
C3—C2—H2119.3O5—C9—C8117.70 (15)
C1—C2—H2119.3O6—C9—C8106.86 (14)
C2—C3—C4123.21 (18)O2—C9—C8104.72 (13)
C2—C3—H3118.4O3—C10—O4123.58 (16)
C4—C3—H3118.4O3—C10—C8125.45 (16)
O2—C4—C5107.74 (15)O4—C10—C8110.94 (15)
O2—C4—C3109.54 (16)O4—C11—H11A109.5
C5—C4—C3112.28 (15)O4—C11—H11B109.5
O2—C4—C7105.29 (13)H11A—C11—H11B109.5
C5—C4—C7111.23 (16)O4—C11—H11C109.5
C3—C4—C7110.48 (16)H11A—C11—H11C109.5
C6—C5—C4123.44 (19)H11B—C11—H11C109.5
C6—C5—H5118.3O5—C12—H12A109.5
C4—C5—H5118.3O5—C12—H12B109.5
C5—C6—C1121.19 (18)H12A—C12—H12B109.5
C5—C6—H6119.4O5—C12—H12C109.5
C1—C6—H6119.4H12A—C12—H12C109.5
C8—C7—C4103.53 (14)H12B—C12—H12C109.5
C8—C7—H7A111.1O6—C13—H13A109.5
C4—C7—H7A111.1O6—C13—H13B109.5
C8—C7—H7B111.1H13A—C13—H13B109.5
C4—C7—H7B111.1O6—C13—H13C109.5
H7A—C7—H7B109.0H13A—C13—H13C109.5
C10—C8—C7114.59 (15)H13B—C13—H13C109.5
O1—C1—C2—C3174.2 (2)C12—O5—C9—O255.5 (2)
C6—C1—C2—C37.7 (3)C12—O5—C9—C863.3 (2)
C1—C2—C3—C43.4 (4)C13—O6—C9—O562.06 (19)
C9—O2—C4—C5122.48 (15)C13—O6—C9—O257.0 (2)
C9—O2—C4—C3115.12 (16)C13—O6—C9—C8171.10 (15)
C9—O2—C4—C73.68 (19)C4—O2—C9—O5151.91 (14)
C2—C3—C4—O2133.2 (2)C4—O2—C9—O690.16 (17)
C2—C3—C4—C513.5 (3)C4—O2—C9—C825.26 (18)
C2—C3—C4—C7111.3 (2)C10—C8—C9—O579.84 (19)
O2—C4—C5—C6134.4 (2)C7—C8—C9—O5157.31 (15)
C3—C4—C5—C613.7 (3)C10—C8—C9—O640.30 (19)
C7—C4—C5—C6110.7 (2)C7—C8—C9—O682.55 (16)
C4—C5—C6—C13.7 (3)C10—C8—C9—O2159.24 (14)
O1—C1—C6—C5174.4 (2)C7—C8—C9—O236.39 (17)
C2—C1—C6—C57.5 (3)C11—O4—C10—O31.8 (3)
O2—C4—C7—C819.56 (19)C11—O4—C10—C8176.39 (16)
C5—C4—C7—C896.87 (18)C7—C8—C10—O311.3 (3)
C3—C4—C7—C8137.73 (16)C9—C8—C10—O3104.0 (2)
C4—C7—C8—C10154.35 (15)C7—C8—C10—O4170.64 (16)
C4—C7—C8—C933.39 (18)C9—C8—C10—O474.07 (19)
C12—O5—C9—O6176.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13A···O3i0.962.603.269 (3)127
Symmetry code: (i) x+1, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC13H16O6
Mr268.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)6.5324 (7), 11.7519 (12), 17.4204 (18)
β (°) 97.723 (2)
V3)1325.2 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.31 × 0.26 × 0.21
Data collection
DiffractometerBruker SMART CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.958, 0.978
No. of measured, independent and
observed [I > 2σ(I)] reflections
7015, 2588, 2140
Rint0.020
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.140, 1.05
No. of reflections2588
No. of parameters175
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.22

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13A···O3i0.962.603.269 (3)127
Symmetry code: (i) x+1, y+1/2, z+1/2.
 

Acknowledgements

This project was sponsored by the National Science Foundation of Jiangsu Province (No. BK2009262) and the Scientific Research Foundation for Returned Overseas Chinese Scholars, State Education Ministry.

References

First citationBayer Aktiengesellschaft (1995). WO Patent No. 9 504 719A1.  Google Scholar
First citationBruker (2000). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationFischer, R. M., Bretschneider, T. S. & Kruger, B.-W. (1993). US Patent No. 5 262 383.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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