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Volume 69 
Part 7 
Pages o1037-o1038  
July 2013  

Received 28 May 2013
Accepted 31 May 2013
Online 8 June 2013

Key indicators
Single-crystal X-ray study
T = 293 K
Mean [sigma](C-C) = 0.007 Å
R = 0.045
wR = 0.108
Data-to-parameter ratio = 19.3
Details
Open access

(1S,2R,7R,8S,10R)-9,9-Dibromo-2,6,6,10-tetramethyl-1[alpha],2[alpha]-epoxytricyclo[5.5.0.08,10]dodecane

aLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco, and bLaboratoire de Chimie du Solide, Appliquée, Faculté des Sciences, Université Mohammed V-Agdal , Avenue Ibn Battouta, BP 1014, Rabat, Morocco
Correspondence e-mail: berraho@uca.ma

The title compound, C16H24Br2O, was synthesized from the reaction of [beta]-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from Atlas cedar (Cedrus atlantica) essential oil, after reaction with dibromocarbene. The asymmetric unit contains two independent molecules with similar conformations. Each molecule is built up from fused six-and seven-membered rings and two three-membered rings. In both molecules, the six-membered ring has an envelope conformation with the flap provided by the C atom of the epoxy ring, whereas the seven-membered ring displays a chair conformation. The crystal packing is governed only by van der Waals interactions. The absolute configuration was established from anomalous dispersion effects.

Related literature

For background to [beta]-himachalene, see: Benharref et al.(2013[Benharref, A., Ourhriss, N., El Ammari, L., Saadi, M. & Berraho, M. (2013). Acta Cryst. E69, o933-o934.]); Oukhrib et al.(2013a[Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013a). Acta Cryst. E69, o521-o522.],b[Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013b). Acta Cryst. E69, o589-o590.]). For the reactivity of this sesquiterpene and its derivatives, see: El Haib et al. (2011[El Haib, A., Benharref, A., Parres-Maynadié, S., Manoury, E., Urrutigoïty, M. & Gouygou, M. (2011). Tetrahedron Asymmetry, 22, 101-108.]). For details of the synthesis, see: El Jamili et al. (2002[El Jamili, H., Auhmani, A., Dakir, M., Lassaba, E., Benharref, A., Pierrot, M., Chiaroni, A. & Riche, C. (2002). Tetrahedron Lett. 43, 6645-6648.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C16H24Br2O

  • Mr = 392.17

  • Monoclinic, P 21

  • a = 8.8056 (13) Å

  • b = 15.648 (3) Å

  • c = 12.1390 (16) Å

  • [beta] = 91.769 (10)°

  • V = 1671.8 (4) Å3

  • Z = 4

  • Mo K[alpha] radiation

  • [mu] = 4.84 mm-1

  • T = 293 K

  • 0.25 × 0.15 × 0.10 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.423, Tmax = 0.617

  • 17250 measured reflections

  • 6776 independent reflections

  • 5298 reflections with I > 2[sigma](I)

  • Rint = 0.081

Refinement
  • R[F2 > 2[sigma](F2)] = 0.045

  • wR(F2) = 0.108

  • S = 0.96

  • 6776 reflections

  • 351 parameters

  • 1 restraint

  • H-atom parameters constrained

  • [Delta][rho]max = 0.71 e Å-3

  • [Delta][rho]min = -0.67 e Å-3

  • Absolute structure: Flack & Bernardinelli (2000[Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst. 33, 1143-1148.])

  • Flack parameter: 0.009 (10)

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: WinGX publication routines (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).


Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ5070 ).


Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

Benharref, A., Ourhriss, N., El Ammari, L., Saadi, M. & Berraho, M. (2013). Acta Cryst. E69, o933-o934.  [CrossRef] [ChemPort] [IUCr Journals]
Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.  [CrossRef] [ChemPort] [Web of Science]
El Haib, A., Benharref, A., Parres-Maynadié, S., Manoury, E., Urrutigoïty, M. & Gouygou, M. (2011). Tetrahedron Asymmetry, 22, 101-108.  [Web of Science] [CrossRef] [ChemPort]
El Jamili, H., Auhmani, A., Dakir, M., Lassaba, E., Benharref, A., Pierrot, M., Chiaroni, A. & Riche, C. (2002). Tetrahedron Lett. 43, 6645-6648.  [ChemPort]
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.  [Web of Science] [CrossRef] [ChemPort] [IUCr Journals]
Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst. 33, 1143-1148.  [Web of Science] [CrossRef] [ChemPort] [IUCr Journals]
Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013a). Acta Cryst. E69, o521-o522.  [CrossRef] [ChemPort] [IUCr Journals]
Oukhrib, A., Benharref, A., Saadi, M., Berraho, M. & El Ammari, L. (2013b). Acta Cryst. E69, o589-o590.  [CrossRef] [ChemPort] [IUCr Journals]
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.  [CrossRef] [ChemPort] [IUCr Journals]


Acta Cryst (2013). E69, o1037-o1038   [ doi:10.1107/S160053681301502X ]

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