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

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Hexa­methyl 13,14-dioxa­penta­cyclo­[8.2.1.14,7.02,9.03,8]tetra­deca-5,11-diene-1,4,5,6,11,12-hexa­carboxyl­ate

aDepartment of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6, and bDepartment of Chemistry, University of Guelph, Guelph, Ontario, Canada N1G 2W1
*Correspondence e-mail: alough@chem.utoronto.ca

(Received 3 September 2012; accepted 13 September 2012; online 22 September 2012)

In the title compound, C24H24O14, the stereochemistry at the cyclo­butane ring is cis-anti-cis and the –COOMe groups in the bicyclic rings are syn to each other. The mol­ecule lies on a twofold rotation axis. In the crystal, weak C—H⋯O hydrogen bonds connect mol­ecules into chains along [001], forming R22(10) rings.

Related literature

For related structures, see: Lough et al. (2012a[Lough, A. J., Jack, K. & Tam, W. (2012a). Acta Cryst. E68, o2961.],b[Lough, A. J., Jack, K. & Tam, W. (2012b). Acta Cryst. E68, o2962.]). For the synthetic background, see: Ballantine et al. (2009[Ballantine, M., Menard, M. L. & Tam, W. (2009). J. Org. Chem. 74, 7570-7573.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C24H24O14

  • Mr = 536.43

  • Monoclinic, C 2/c

  • a = 25.1309 (18) Å

  • b = 10.0840 (7) Å

  • c = 9.5922 (7) Å

  • β = 95.430 (2)°

  • V = 2419.9 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 147 K

  • 0.15 × 0.10 × 0.07 mm

Data collection
  • Bruker Kappa APEX DUO CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.711, Tmax = 0.746

  • 11038 measured reflections

  • 2787 independent reflections

  • 2366 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.098

  • S = 1.04

  • 2787 reflections

  • 175 parameters

  • H-atom parameters constrained

  • Δρmax = 0.42 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯O1i 1.00 2.38 3.2105 (13) 140
Symmetry code: (i) [x, -y+1, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

We have recently investigated the Ru-catalyzed isomerization and dimerization reaction of oxanorbornadiene compounds (Ballantine et al., 2009). When dissolved in 1,2-dichloroethane in the presence of Cp*Ru(COD)Cl, 1,2,3-trimethyl-7-oxabicyclo[2,2,1]hepta-2,5-diene-1,2,3-tricarboxylate will dimerize into (I) (Fig. 1). The desired product was resolved using fractional crystallization in methanol. The stereochemistry and regioschemistry of the product was determined by this single-crystal X-ray analysis. The only dimer product obtained was found to have a cis-anti-cis stereochemistry at the cyclobutane ring of the dimer, and the two COOMe groups in the bicyclic rings are syn to each other.

The molecular structure of (I) is shown in Fig. 2. The molecule lies on a twofold rotation axis. In the crystal, weak C—H···O hydrogen bonds connect molecules into one-dimensional chains (Fig. 3) along [001] forming R22(10) rings (Bernstein et al., 1995).

For related structures, see the two preceding papers (Lough et al., 2012a,b).

Related literature top

For related structures, see: Lough et al. (2012a,b). For the synthetic background, see: Ballantine et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

1,2,3-Trimethyl-7-oxabicyclo[2,2,1]hepta-2,5-diene-1,2,3-tricarboxylate (316 mg, 1.2 mmol) was weighed into an oven-dried vial, purged with nitrogen and transferred into a Dry Box. In the Dry Box, Cp*Ru(COD)Cl (10 mol%) was added to another oven dried vial and dissolved in 1,2-dichloroethane (2 ml). The Ru-catalyst was then transferred into the vial containing the 7-oxanorbornadiene. The vial was sealed with a screw cap and removed from the Dry Box. The reaction was heated at 333 K with stirring for 18 h. The crude product was purified by column chromatography (EtOAc:hexanes=2:3) followed by recrystallization in methanol to give the dimer (I). Colourless needles were grown by slow evaportation of a solution of (I) in methanol.

Refinement top

Hydrogen atoms were placed in calculated positions with C—H distances of 0.98 and 1.00 Å. They were included in the refinement in a riding-model approximation with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(Cmethyl).

Structure description top

We have recently investigated the Ru-catalyzed isomerization and dimerization reaction of oxanorbornadiene compounds (Ballantine et al., 2009). When dissolved in 1,2-dichloroethane in the presence of Cp*Ru(COD)Cl, 1,2,3-trimethyl-7-oxabicyclo[2,2,1]hepta-2,5-diene-1,2,3-tricarboxylate will dimerize into (I) (Fig. 1). The desired product was resolved using fractional crystallization in methanol. The stereochemistry and regioschemistry of the product was determined by this single-crystal X-ray analysis. The only dimer product obtained was found to have a cis-anti-cis stereochemistry at the cyclobutane ring of the dimer, and the two COOMe groups in the bicyclic rings are syn to each other.

The molecular structure of (I) is shown in Fig. 2. The molecule lies on a twofold rotation axis. In the crystal, weak C—H···O hydrogen bonds connect molecules into one-dimensional chains (Fig. 3) along [001] forming R22(10) rings (Bernstein et al., 1995).

For related structures, see the two preceding papers (Lough et al., 2012a,b).

For related structures, see: Lough et al. (2012a,b). For the synthetic background, see: Ballantine et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Reaction scheme
[Figure 2] Fig. 2. The molecular structure of (I) showing 30% probability ellipsoids (symmetry code (a): -x + 2, y, -z + 1/2).
[Figure 3] Fig. 3. Part of the crystal structure showing weak hydrogen bonds as dashed lines.
Hexamethyl 13,14-dioxapentacyclo[8.2.1.14,7.02,9.03,8]tetradeca- 5,11-diene-1,4,5,6,11,12-hexacarboxylate top
Crystal data top
C24H24O14F(000) = 1120
Mr = 536.43Dx = 1.472 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 6078 reflections
a = 25.1309 (18) Åθ = 3.0–27.5°
b = 10.0840 (7) ŵ = 0.12 mm1
c = 9.5922 (7) ÅT = 147 K
β = 95.430 (2)°Needle, colourless
V = 2419.9 (3) Å30.15 × 0.10 × 0.07 mm
Z = 4
Data collection top
Bruker Kappa APEX DUO CCD
diffractometer
2787 independent reflections
Radiation source: fine-focus sealed tube2366 reflections with I > 2σ(I)
Bruker Triumph monochromatorRint = 0.028
φ and ω scansθmax = 27.5°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 3232
Tmin = 0.711, Tmax = 0.746k = 1312
11038 measured reflectionsl = 1112
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0518P)2 + 1.6228P]
where P = (Fo2 + 2Fc2)/3
2787 reflections(Δ/σ)max = 0.001
175 parametersΔρmax = 0.42 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C24H24O14V = 2419.9 (3) Å3
Mr = 536.43Z = 4
Monoclinic, C2/cMo Kα radiation
a = 25.1309 (18) ŵ = 0.12 mm1
b = 10.0840 (7) ÅT = 147 K
c = 9.5922 (7) Å0.15 × 0.10 × 0.07 mm
β = 95.430 (2)°
Data collection top
Bruker Kappa APEX DUO CCD
diffractometer
2787 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
2366 reflections with I > 2σ(I)
Tmin = 0.711, Tmax = 0.746Rint = 0.028
11038 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 1.04Δρmax = 0.42 e Å3
2787 reflectionsΔρmin = 0.25 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
O10.92545 (3)0.44122 (8)0.38295 (8)0.01527 (19)
O20.91010 (5)0.09784 (10)0.30367 (10)0.0322 (3)
O30.94389 (4)0.20695 (9)0.49626 (9)0.0237 (2)
O40.80179 (4)0.21560 (10)0.15093 (10)0.0272 (2)
O50.85951 (3)0.23192 (9)0.01412 (9)0.0206 (2)
O60.84027 (4)0.69996 (9)0.08929 (10)0.0250 (2)
O70.80331 (4)0.50766 (9)0.00853 (10)0.0227 (2)
C10.97293 (4)0.35610 (11)0.20451 (11)0.0133 (2)
H10.97230.31060.11170.016*
C20.92422 (4)0.33021 (12)0.28941 (11)0.0141 (2)
C30.87579 (4)0.36255 (12)0.18620 (11)0.0149 (2)
C40.87513 (5)0.49467 (12)0.17852 (12)0.0157 (2)
C50.92285 (4)0.54296 (12)0.27571 (11)0.0149 (2)
H5A0.92020.63610.31030.018*
C60.97323 (4)0.51140 (11)0.20141 (11)0.0134 (2)
H60.97480.55280.10710.016*
C70.92448 (5)0.19809 (12)0.36304 (12)0.0171 (3)
C80.93932 (6)0.08885 (15)0.58051 (15)0.0322 (3)
H8A0.95900.10180.67260.048*
H8B0.95430.01290.53380.048*
H8C0.90160.07210.59200.048*
C90.84091 (5)0.26211 (12)0.10758 (12)0.0165 (2)
C100.82628 (5)0.14106 (15)0.10214 (14)0.0263 (3)
H10A0.84000.13450.19420.039*
H10B0.78950.17420.11340.039*
H10C0.82700.05330.05820.039*
C110.83860 (4)0.58061 (13)0.08826 (12)0.0170 (2)
C120.76407 (5)0.58064 (14)0.08202 (15)0.0266 (3)
H12A0.74290.51850.14330.040*
H12B0.78240.64330.13920.040*
H12C0.74040.62940.02470.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0186 (4)0.0149 (4)0.0123 (4)0.0003 (3)0.0013 (3)0.0014 (3)
O20.0547 (7)0.0168 (5)0.0246 (5)0.0047 (4)0.0011 (4)0.0007 (4)
O30.0295 (5)0.0222 (5)0.0183 (4)0.0033 (4)0.0035 (4)0.0069 (4)
O40.0228 (5)0.0311 (6)0.0287 (5)0.0110 (4)0.0078 (4)0.0079 (4)
O50.0188 (4)0.0252 (5)0.0177 (4)0.0039 (3)0.0015 (3)0.0053 (4)
O60.0227 (5)0.0180 (5)0.0329 (5)0.0026 (3)0.0045 (4)0.0004 (4)
O70.0180 (4)0.0207 (5)0.0274 (5)0.0002 (3)0.0091 (4)0.0033 (4)
C10.0127 (5)0.0146 (6)0.0120 (5)0.0002 (4)0.0012 (4)0.0003 (4)
C20.0143 (5)0.0150 (6)0.0127 (5)0.0004 (4)0.0001 (4)0.0018 (4)
C30.0116 (5)0.0190 (6)0.0142 (5)0.0004 (4)0.0009 (4)0.0002 (4)
C40.0121 (5)0.0188 (6)0.0160 (5)0.0002 (4)0.0002 (4)0.0011 (4)
C50.0154 (5)0.0138 (6)0.0153 (5)0.0013 (4)0.0004 (4)0.0001 (4)
C60.0133 (5)0.0138 (6)0.0126 (5)0.0004 (4)0.0019 (4)0.0001 (4)
C70.0166 (6)0.0179 (6)0.0174 (6)0.0007 (4)0.0038 (4)0.0013 (5)
C80.0412 (8)0.0286 (8)0.0263 (7)0.0004 (6)0.0011 (6)0.0140 (6)
C90.0139 (5)0.0180 (6)0.0172 (5)0.0004 (4)0.0007 (4)0.0001 (5)
C100.0243 (7)0.0316 (8)0.0223 (6)0.0046 (5)0.0013 (5)0.0102 (6)
C110.0125 (5)0.0196 (6)0.0188 (5)0.0009 (4)0.0013 (4)0.0003 (5)
C120.0193 (6)0.0274 (7)0.0306 (7)0.0005 (5)0.0106 (5)0.0074 (6)
Geometric parameters (Å, º) top
O1—C21.4331 (14)C3—C41.3343 (17)
O1—C51.4500 (14)C3—C91.4960 (16)
O2—C71.1991 (16)C4—C111.4808 (16)
O3—C71.3271 (15)C4—C51.5275 (15)
O3—C81.4499 (16)C5—C61.5435 (16)
O4—C91.1987 (15)C5—H5A1.0000
O5—C91.3331 (15)C6—C6i1.563 (2)
O5—C101.4547 (15)C6—H61.0000
O6—C111.2043 (16)C8—H8A0.9800
O7—C111.3358 (15)C8—H8B0.9800
O7—C121.4514 (14)C8—H8C0.9800
C1—C1i1.545 (2)C10—H10A0.9800
C1—C21.5553 (15)C10—H10B0.9800
C1—C61.5663 (16)C10—H10C0.9800
C1—H11.0000C12—H12A0.9800
C2—C71.5076 (16)C12—H12B0.9800
C2—C31.5295 (15)C12—H12C0.9800
C2—O1—C596.42 (8)C5—C6—H6115.8
C7—O3—C8116.11 (11)C6i—C6—H6115.8
C9—O5—C10114.99 (10)C1—C6—H6115.8
C11—O7—C12116.12 (10)O2—C7—O3125.51 (12)
C1i—C1—C2113.51 (11)O2—C7—C2122.33 (11)
C1i—C1—C690.30 (5)O3—C7—C2112.12 (10)
C2—C1—C6100.56 (9)O3—C8—H8A109.5
C1i—C1—H1116.2O3—C8—H8B109.5
C2—C1—H1116.2H8A—C8—H8B109.5
C6—C1—H1116.2O3—C8—H8C109.5
O1—C2—C7113.46 (9)H8A—C8—H8C109.5
O1—C2—C3101.97 (9)H8B—C8—H8C109.5
C7—C2—C3117.36 (10)O4—C9—O5125.55 (11)
O1—C2—C1103.01 (9)O4—C9—C3123.42 (11)
C7—C2—C1115.14 (9)O5—C9—C3111.03 (10)
C3—C2—C1104.05 (9)O5—C10—H10A109.5
C4—C3—C9130.13 (11)O5—C10—H10B109.5
C4—C3—C2104.70 (10)H10A—C10—H10B109.5
C9—C3—C2125.05 (10)O5—C10—H10C109.5
C3—C4—C11128.35 (11)H10A—C10—H10C109.5
C3—C4—C5106.24 (10)H10B—C10—H10C109.5
C11—C4—C5125.29 (11)O6—C11—O7125.15 (11)
O1—C5—C4100.80 (9)O6—C11—C4124.12 (11)
O1—C5—C6101.41 (9)O7—C11—C4110.72 (11)
C4—C5—C6106.46 (9)O7—C12—H12A109.5
O1—C5—H5A115.4O7—C12—H12B109.5
C4—C5—H5A115.4H12A—C12—H12B109.5
C6—C5—H5A115.4O7—C12—H12C109.5
C5—C6—C6i114.97 (11)H12A—C12—H12C109.5
C5—C6—C1101.06 (9)H12B—C12—H12C109.5
C6i—C6—C189.66 (5)
C5—O1—C2—C7178.09 (9)O1—C5—C6—C137.92 (10)
C5—O1—C2—C350.92 (9)C4—C5—C6—C167.09 (10)
C5—O1—C2—C156.76 (9)C1i—C1—C6—C5117.62 (10)
C1i—C1—C2—O162.75 (8)C2—C1—C6—C53.62 (10)
C6—C1—C2—O132.23 (10)C1i—C1—C6—C6i2.22 (12)
C1i—C1—C2—C761.30 (10)C2—C1—C6—C6i111.78 (10)
C6—C1—C2—C7156.28 (9)C8—O3—C7—O210.06 (19)
C1i—C1—C2—C3168.84 (6)C8—O3—C7—C2172.22 (11)
C6—C1—C2—C373.86 (10)O1—C2—C7—O2160.49 (12)
O1—C2—C3—C432.45 (11)C3—C2—C7—O241.86 (17)
C7—C2—C3—C4157.06 (10)C1—C2—C7—O281.16 (15)
C1—C2—C3—C474.43 (11)O1—C2—C7—O321.71 (14)
O1—C2—C3—C9151.28 (10)C3—C2—C7—O3140.34 (10)
C7—C2—C3—C926.67 (16)C1—C2—C7—O396.65 (12)
C1—C2—C3—C9101.85 (12)C10—O5—C9—O44.24 (18)
C9—C3—C4—C110.3 (2)C10—O5—C9—C3176.27 (10)
C2—C3—C4—C11176.35 (11)C4—C3—C9—O494.36 (17)
C9—C3—C4—C5175.80 (11)C2—C3—C9—O490.36 (16)
C2—C3—C4—C50.21 (12)C4—C3—C9—O586.14 (16)
C2—O1—C5—C450.47 (9)C2—C3—C9—O589.15 (13)
C2—O1—C5—C658.97 (9)C12—O7—C11—O60.57 (18)
C3—C4—C5—O132.25 (12)C12—O7—C11—C4178.21 (10)
C11—C4—C5—O1151.47 (11)C3—C4—C11—O6178.87 (13)
C3—C4—C5—C673.20 (12)C5—C4—C11—O65.68 (19)
C11—C4—C5—C6103.08 (12)C3—C4—C11—O70.08 (18)
O1—C5—C6—C6i56.92 (8)C5—C4—C11—O7175.53 (11)
C4—C5—C6—C6i161.93 (7)
Symmetry code: (i) x+2, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1ii1.002.383.2105 (13)140
Symmetry code: (ii) x, y+1, z1/2.

Experimental details

Crystal data
Chemical formulaC24H24O14
Mr536.43
Crystal system, space groupMonoclinic, C2/c
Temperature (K)147
a, b, c (Å)25.1309 (18), 10.0840 (7), 9.5922 (7)
β (°) 95.430 (2)
V3)2419.9 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.15 × 0.10 × 0.07
Data collection
DiffractometerBruker Kappa APEX DUO CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.711, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
11038, 2787, 2366
Rint0.028
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.098, 1.04
No. of reflections2787
No. of parameters175
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.42, 0.25

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O1i1.002.383.2105 (13)140
Symmetry code: (i) x, y+1, z1/2.
 

Acknowledgements

The University of Toronto thanks NSERC Canada for funding.

References

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