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Acta Crystallogr Sect E Struct Rep Online. 2008 June 1; 64(Pt 6): o1172.
Published online 2008 May 30. doi:  10.1107/S1600536808015377
PMCID: PMC2961570

cis-9,10-Bis(bromo­meth­yl)-1,4,5,8-tetra­oxadeca­lin

Abstract

The title compound, C8H12Br2O4, is a bicyclic ketal in which the two six-membered rings are cis to one another and assume a double-chair conformation. A crystallographic twofold axis bisects the molecule.

Related literature

A determination of this structure has been previously attempted (Fuchs et al., 1972 [triangle]), but the authors did not publish or deposit any atomic coordinates. The same paper gives detailed information for a related structure which has H atoms in place of the bromo­methyl groups of the title compound. A search of the Cambridge Structural Database [Version 5.29; (Allen, 2002 [triangle]); CONQUEST (Bruno et al., 2002 [triangle])] did not yield any other closely related structures. See also: Fuchs (1970 [triangle]).

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Object name is e-64-o1172-scheme1.jpg

Experimental

Crystal data

  • C8H12Br2O4
  • M r = 332
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1172-efi2.jpg
  • a = 8.5314 (14) Å
  • b = 9.5295 (7) Å
  • c = 13.1348 (13) Å
  • V = 1067.9 (2) Å3
  • Z = 4
  • Cu Kα radiation
  • μ = 9.57 mm−1
  • T = 295 (2) K
  • 0.5 × 0.3 × 0.15 mm

Data collection

  • Enra–Nonius CAD4 diffractometer
  • Absorption correction: multi-scan (Blessing, 1995 [triangle]) T min = 0.039, T max = 0.486 (expected range = 0.019–0.238)
  • 4584 measured reflections
  • 968 independent reflections
  • 915 reflections with I > 2σ(I)
  • R int = 0.063
  • 3 standard reflections every 67 reflections intensity decay: 3%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.036
  • wR(F 2) = 0.101
  • S = 1.10
  • 968 reflections
  • 65 parameters
  • H-atom parameters constrained
  • Δρmax = 0.45 e Å−3
  • Δρmin = −0.43 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 [triangle]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 [triangle]); program(s) used to solve structure: DIRDIF (Beurskens et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808015377/fj2094sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808015377/fj2094Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported in part by funds provided by the University of North Carolina at Charlotte.

supplementary crystallographic information

Comment

The title compound is a bicyclic ketal in which the two six-membered rings are cis to one another and assume a doublechair conformation. A crystallographic twofold axis relates one of the fused rings to the other.

A determination of this structure has been previously attempted (Fuchs et al., 1972), but the authors did not publish or deposit any atomic coordinates. They halted their study after three cycles of isotropic refinement because "···the accuracy of the atomic parameters was relatively low." They did present the Fourier map resulting from the isotropic refinement, and it shows an overall structure in agreement with that presented here. The space group and unit-cell parameters which they obtained are also in agreement with those of the present study.

The authors of this prior study attributed the "relatively low" accuracy of their atomic parameters to the domination of the scattering by the Br atoms. Our present study suggests that the importance of absorption corrections probably played a part as well.

The same paper (Fuchs et al., 1972) gives detailed structural information for a related compound which has hydrogen atoms in place of the bromomethyl groups of the title compound. That structure is similar to the one reported here, in that the two six-membered rings are cis to one another and assume a doublechair conformation.

Experimental

The title compound 3 has been described as the major reaction product in the acid-catalyzed reaction of diketone 1 with ethylene glycol (Fuchs, 1970). Since the dispiro derivative 2 was needed for one of our projects, literature procedures (Fuchs et al., 1972) were followed to yield a product mixture from which only the bicyclic title compound 3 could be isolated, as colorless crystals. The NMR data obtained for 3 deviated from the published data (Fuchs, 1970), and the X-ray structure was therefore determined to ultimately confirm the formation of 3.

1H NMR (CDCl3, 500 MHz): δ = 4.14 (mc, 4H), 3.75 (mc, 4H), 3.69 (s, 4H) p.p.m..

13C NMR (CDCl3, 125.7 MHz): δ = 92.3, 61.1, 31.6 p.p.m..

Refinement

All H atoms were constrained using a riding model. C — H bond lengths were fixed at 0.97 Å, with Uiso(H) = 1.2 Ueq. (C).

Figures

Fig. 1.
View of the title compound, 3, with 50% probability displacement ellipsoids. [Symmetry code: (') -x + 1/2, -y + 1, z.]
Fig. 2.
Schematic representations of compounds 1–4.

Crystal data

C8H12Br2O4F000 = 648
Mr = 332Dx = 2.065 Mg m3
Orthorhombic, PncaCu Kα radiation λ = 1.54184 Å
Hall symbol: -P 2a 2nCell parameters from 23 reflections
a = 8.5314 (14) Åθ = 9.7–23.5º
b = 9.5295 (7) ŵ = 9.57 mm1
c = 13.1348 (13) ÅT = 295 (2) K
V = 1067.9 (2) Å3Irregular, colorless
Z = 40.5 × 0.3 × 0.15 mm

Data collection

Enra–Nonius CAD4 diffractometerRint = 0.063
Radiation source: normal-focus sealed tubeθmax = 67.6º
Monochromator: graphiteθmin = 5.7º
Non–profiled ω/2θ scansh = −10→10
Absorption correction: multi-scan(Blessing, 1995)k = −11→0
Tmin = 0.039, Tmax = 0.486l = −15→15
4584 measured reflections3 standard reflections
968 independent reflections every 67 reflections
915 reflections with I > 2σ(I) intensity decay: 3%

Refinement

Refinement on F2H-atom parameters constrained
Least-squares matrix: full  w = 1/[σ2(Fo2) + (0.0428P)2 + 0.7055P] where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.036(Δ/σ)max < 0.001
wR(F2) = 0.101Δρmax = 0.45 e Å3
S = 1.10Δρmin = −0.43 e Å3
968 reflectionsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
65 parametersExtinction coefficient: 0.0045 (3)

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Br0.12607 (5)0.16873 (4)0.02778 (4)0.0766 (3)
O20.0390 (2)0.4700 (2)0.13501 (17)0.0603 (6)
O10.2328 (3)0.3492 (2)0.21071 (17)0.0605 (6)
C40.2152 (4)0.3552 (3)0.0252 (2)0.0588 (8)
H4A0.32560.34830.00830.071*
H4B0.16440.4092−0.0280.071*
C30.0090 (4)0.5542 (4)0.2241 (3)0.0672 (9)
H3A0.03540.50120.28480.081*
H3B−0.10150.57790.22730.081*
C10.1982 (3)0.4327 (3)0.1255 (2)0.0545 (7)
C20.3958 (4)0.3150 (4)0.2203 (3)0.0680 (10)
H2A0.42840.25830.16280.082*
H2B0.41250.26090.28190.082*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br0.0951 (5)0.0623 (4)0.0725 (4)−0.00632 (17)−0.00192 (18)−0.00707 (17)
O20.0530 (11)0.0674 (14)0.0606 (12)0.0026 (10)0.0035 (10)−0.0047 (11)
O10.0656 (13)0.0620 (13)0.0539 (12)0.0008 (10)−0.0008 (11)0.0060 (10)
C40.0597 (18)0.0570 (18)0.060 (2)0.0007 (14)0.0019 (14)−0.0019 (14)
C30.0648 (19)0.073 (2)0.064 (2)0.0056 (16)0.0107 (17)−0.0070 (17)
C10.0510 (15)0.0600 (19)0.0525 (17)0.0049 (13)0.0015 (13)−0.0006 (13)
C20.072 (2)0.069 (2)0.063 (2)0.0096 (16)−0.0108 (17)0.0074 (17)

Geometric parameters (Å, °)

Br—C41.933 (3)C4—H4B0.97
O2—C11.409 (4)C3—C2i1.489 (5)
O2—C31.442 (4)C3—H3A0.97
O1—C11.404 (4)C3—H3B0.97
O1—C21.434 (4)C1—C1i1.558 (6)
C4—C11.518 (4)C2—H2A0.97
C4—H4A0.97C2—H2B0.97
C1—O2—C3112.5 (2)H3A—C3—H3B108.2
C1—O1—C2113.7 (3)O1—C1—O2105.9 (2)
C1—C4—Br113.2 (2)O1—C1—C4113.3 (3)
C1—C4—H4A108.9O2—C1—C4107.0 (3)
Br—C4—H4A108.9O1—C1—C1i110.3 (2)
C1—C4—H4B108.9O2—C1—C1i109.8 (3)
Br—C4—H4B108.9C4—C1—C1i110.3 (2)
H4A—C4—H4B107.7O1—C2—C3i110.0 (3)
O2—C3—C2i110.0 (3)O1—C2—H2A109.7
O2—C3—H3A109.7C3i—C2—H2A109.7
C2i—C3—H3A109.7O1—C2—H2B109.7
O2—C3—H3B109.7C3i—C2—H2B109.7
C2i—C3—H3B109.7H2A—C2—H2B108.2

Symmetry codes: (i) −x+1/2, −y+1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: FJ2094).

References

  • Allen, F. H. (2002). Acta Cryst. B58, 380–388. [PubMed]
  • Beurskens, P. T., Beurskens, G., de Gelder, R., Garciía-Granda, S., Gould, R. O., Israel, R. & Smits, J. M. M. (1999). The DIRDIF99 program system. Technical Report of the Crystallography Laboratory, University of Nijmegen, The Netherlands.
  • Blessing, R. H. (1995). Acta Cryst. A51, 33–38. [PubMed]
  • Bruno, I. J., Cole, J. C., Edgington, P. R., Kessler, M., Macrae, C. F., McCabe, P., Pearson, J. & Taylor, R. (2002). Acta Cryst. B58, 389–397. [PubMed]
  • Enraf–Nonius (1994). CAD-4 EXPRESS Enraf–Nonius, Delft, The Netherlands.
  • Farrugia, L. J. (1997). J. Appl. Cryst.30, 565.
  • Farrugia, L. J. (1999). J. Appl. Cryst.32, 837–838.
  • Fuchs, B. (1970). Tetrahedron Lett.20, 1747–1750.
  • Fuchs, B., Goldberg, I. & Shmueli, U. (1972). J. Chem. Soc. Perkin Trans. 2, pp. 357–365.
  • Harms, K. & Wocadlo, S. (1995). XCAD4 University of Marburg, Germany.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography