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

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ISSN: 2056-9890

(1S,3R,8R)-2,2-Di­chloro-3,7,7,10-tetra­methyl­tri­cyclo­[6.4.0.01,3]dodec-9-en-11-one

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 de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: berraho@uca.ma

(Received 29 April 2013; accepted 30 April 2013; online 4 May 2013)

The title compound, C16H22Cl2O, was synthesized from β-himachalene (3,5,5,9-tetra­methyl-2,4a,5,6,7,8-hexa­hydro-1H-benzo­cyclo­heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol­ecule is built up from fused six- and seven-membered rings and an additional three-membered ring arising from the reaction of himachalene with di­chloro­carbene. The six-membered ring has an envelope conformation, with the C atom belonging to the three-membered ring forming the flap, whereas the seven-membered ring displays a screw-boat conformation; the dihedral angle between the rings (all atoms) is 59.65 (14)°.

Related literature

For background to the essential oil of the Alas cedar (Cedrus atlantica), see: Joseph & Dev (1968[Joseph, T. C. & Dev, S. (1968). Tetrahedron, 24, 3841-3859.]); Plattier & Teiseire (1974[Plattier, M. & Teiseire, P. (1974). Recherche, 19, 131-144.]). For the reactivity and biological properties of β-himachalene, see: Benharref et al. (2012[Benharref, A., El Ammari, L., Lassaba, E., Ourhriss, N. & Berraho, M. (2012). Acta Cryst. E68, o2502.]); Chekroun et al. (2000[Chekroun, A., Jarid, A., Benharref, A. & Boutalib, A. (2000). J. Org. Chem. 65, 4431-4434.]); 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.]); Lassaba et al. (1998[Lassaba, E., Eljamili, H., Chekroun, A., Benharref, A., Chiaroni, A., Riche, C. & Lavergne, J.-P. (1998). Synth. Commun. 28, 2641-2651.]); Dakir et al. (2004[Dakir, M., Auhmani, A., Ait Itto, M. Y., Mazoir, N., Akssira, M., Pierrot, M. & Benharref, A. (2004). Synth. Commun. 34, 2001-2008.]); Daoubi et al. (2004[Daoubi, M., Duran -Patron, R., Hmamouchi, M., Hernandez-Galan, R., Benharref, A. & Isidro, G. C. (2004). Pest Manag. Sci. 60, 927-932.]). For conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C16H22Cl2O

  • Mr = 301.24

  • Monoclinic, P 21

  • a = 8.8780 (3) Å

  • b = 10.3340 (3) Å

  • c = 8.9230 (3) Å

  • β = 108.805 (4)°

  • V = 774.94 (4) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 3.67 mm−1

  • T = 180 K

  • 0.30 × 0.25 × 0.21 mm

Data collection
  • Agilent Xcalibur (Eos, Gemini ultra) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010[Agilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.761, Tmax = 1.000

  • 2787 measured reflections

  • 1835 independent reflections

  • 1779 reflections with I > 2σ(I)

  • Rint = 0.027

  • θmax = 60.6°

Refinement
  • R[F2 > 2σ(F2)] = 0.028

  • wR(F2) = 0.065

  • S = 1.03

  • 1835 reflections

  • 176 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.16 e Å−3

  • Δρmin = −0.17 e Å−3

  • Absolute structure: Flack & Bernardinelli (2000[Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst. 33, 1143-1148.]), 614 Friedel pairs

  • Flack parameter: 0.014 (15)

Data collection: CrysAlis PRO (Agilent, 2010[Agilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

The essential oil of the Alas cedar (Cedrus atlantica) consist mainly (50%) of a bicyclic hydrocarbon called essential oil of the Alas cedar (Cedrus atlantica) consist mainly (50%) of a bicyclic hydrocarbon called (Joseph & Dev, 1968; Plattier & Teiseire, 1974). The reactivity of this sesquiterpene and its derivatives has been studied extensively by our team in order to prepare new products having biological proprieties (Lassaba et al., 1998; Chekroun et al., 2000; El Jamili et al., 2002; Dakir et al., 2004; Benharref et al. 2012). Indeed, these compounds were tested, using the food poisoning technique, for their potential antifungal activity against phytopathogen Botrytis cinerea (Daoubi et al., 2004). We present here the crystal structure of the title compound, (1S,3R,8R)-2,2-dichloro-3,7,7,10-tetramethyltricyclo [6.4.0.01,3]dodec-9-en-10-one. The molecule is built up from two fused six-and seven- membered rings and an additional three-membered ring from the reaction with the carbene (Fig. 1). The six-membered ring has an envelope conformation, as indicated by the total puckering amplitude QT = 0.453 (3) Å and spherical polar angle θ = 123.4 (4)° with ϕ = 170.0 (4)°, whereas the seven-membered ring display a boat conformation with QT = 1.1545 (3) Å, θ = 87.74 (2)°, ϕ2 = -48.13 (14)° and ϕ3 = -134.45 (4)° (Cremer & Pople, 1975). Owing to the presence of Cl atoms, the absolute configuration could be fully confirmed, by refining the Flack parameter (Flack & Bernardinelli, 2000) as C1(S), C3(R) and C8(R).

Related literature top

For background to the essential oil of the Alas cedar (Cedrus atlantica), see: Joseph & Dev (1968); Plattier & Teiseire (1974). For the reactivity and biological properties of β-himachalene, see: Benharref et al. (2012); Chekroun et al. (2000); El Jamili et al. (2002); Lassaba et al. (1998); Dakir et al. (2004); Daoubi et al. (2004). For conformational analysis, see: Cremer & Pople (1975).

Experimental top

In a reactor containing a solution of (1S, 3R, 8R)-2,2- dichloro-3,7,7,10 tetramethyltricyclo [6.4.0.01,3] dodec-9-ene (1 g, 3.48 mmol) (El Jamili et al., 2002) in 50 ml tetrahydrofuran and water (THF/H2O) (4:1) cooled to 273 K and kept in the dark, was added in small portions 1.23 g (6.96 mmol) of N-bromosccinimide (NBS). The reaction mixture was left stirring for 1 h, after which 20 ml of a saturated solution of NaHCO3 was added. Subsequently, the extraction was performed three times with diethyl ether (3x 20 ml). The organic extracts were dried over Na2SO4, filtered, concentrated, and chromatographed. The title compound was obtained with a yield of 80% and was recrystallized from its hexane solution.

Refinement top

All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl),0.97 Å (methylene), 0.98 Å (methine) with Uiso(H) = 1.2Ueq(methylene, methine) or Uiso(H) = 1.5Ueq(methyl). Owing to the tiny size of the crystal and to define the correct absolute structure determination, the data were collected using Cu radiation.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii.
(1S,3R,8R)-2,2-Dichloro-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-en-11-one top
Crystal data top
C16H22Cl2OF(000) = 320
Mr = 301.24Dx = 1.291 Mg m3
Monoclinic, P21Cu Kα radiation, λ = 1.5418 Å
Hall symbol: P 2ybCell parameters from 1955 reflections
a = 8.8780 (3) Åθ = 4.3–60.5°
b = 10.3340 (3) ŵ = 3.67 mm1
c = 8.9230 (3) ÅT = 180 K
β = 108.805 (4)°Block, colourless
V = 774.94 (4) Å30.30 × 0.25 × 0.21 mm
Z = 2
Data collection top
Agilent Xcalibur (Eos, Gemini ultra)
diffractometer
1835 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source1779 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.027
Detector resolution: 16.1978 pixels mm-1θmax = 60.6°, θmin = 5.2°
ω scansh = 98
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
k = 1111
Tmin = 0.761, Tmax = 1.000l = 810
2787 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)] = 0.028H-atom parameters constrained
wR(F2) = 0.065 w = 1/[σ2(Fo2) + (0.0268P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
1835 reflectionsΔρmax = 0.16 e Å3
176 parametersΔρmin = 0.17 e Å3
1 restraintAbsolute structure: Flack & Bernardinelli (2000), 614 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.014 (15)
Crystal data top
C16H22Cl2OV = 774.94 (4) Å3
Mr = 301.24Z = 2
Monoclinic, P21Cu Kα radiation
a = 8.8780 (3) ŵ = 3.67 mm1
b = 10.3340 (3) ÅT = 180 K
c = 8.9230 (3) Å0.30 × 0.25 × 0.21 mm
β = 108.805 (4)°
Data collection top
Agilent Xcalibur (Eos, Gemini ultra)
diffractometer
1835 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
1779 reflections with I > 2σ(I)
Tmin = 0.761, Tmax = 1.000Rint = 0.027
2787 measured reflectionsθmax = 60.6°
Refinement top
R[F2 > 2σ(F2)] = 0.028H-atom parameters constrained
wR(F2) = 0.065Δρmax = 0.16 e Å3
S = 1.03Δρmin = 0.17 e Å3
1835 reflectionsAbsolute structure: Flack & Bernardinelli (2000), 614 Friedel pairs
176 parametersAbsolute structure parameter: 0.014 (15)
1 restraint
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Cl10.37702 (8)0.87301 (6)0.63481 (9)0.04024 (19)
Cl20.53172 (8)0.67535 (7)0.51438 (9)0.0422 (2)
O10.7317 (2)0.4592 (2)0.9131 (3)0.0472 (6)
C10.3527 (3)0.6081 (2)0.7144 (3)0.0230 (6)
C20.3817 (3)0.7052 (2)0.6004 (3)0.0278 (6)
C30.2321 (3)0.6249 (2)0.5493 (3)0.0280 (6)
C40.0763 (3)0.6914 (3)0.5429 (3)0.0367 (7)
H4A0.01960.71900.43290.044*
H4B0.10000.76960.61050.044*
C50.0311 (3)0.6006 (3)0.5995 (4)0.0417 (8)
H5A0.10980.65360.62940.050*
H5B0.09060.54460.51000.050*
C60.0567 (3)0.5144 (3)0.7398 (3)0.0366 (7)
H6A0.12020.45100.70250.044*
H6B0.02410.46500.77080.044*
C70.1685 (3)0.5800 (3)0.8897 (3)0.0310 (6)
C80.3075 (3)0.6569 (3)0.8553 (3)0.0249 (6)
H80.26770.74730.82850.030*
C90.4529 (3)0.6672 (3)0.9982 (3)0.0276 (6)
H90.44530.71951.08300.033*
C100.5923 (3)0.6092 (3)1.0171 (3)0.0289 (7)
C110.6079 (3)0.5170 (3)0.8973 (3)0.0289 (6)
C120.4618 (3)0.4911 (2)0.7555 (3)0.0276 (6)
H12A0.40280.41660.77880.033*
H12B0.49530.46810.66330.033*
C130.2113 (4)0.5220 (3)0.4243 (3)0.0410 (7)
H13A0.16230.56020.31930.061*
H13B0.14260.45300.44110.061*
H13C0.31540.48580.43130.061*
C140.0742 (4)0.6748 (4)0.9559 (4)0.0483 (8)
H14A0.03280.74470.87940.072*
H14B0.14390.71141.05550.072*
H14C0.01450.62940.97530.072*
C150.2324 (4)0.4722 (3)1.0132 (3)0.0422 (8)
H15A0.30110.51031.11230.063*
H15B0.29370.41010.97330.063*
H15C0.14290.42771.03260.063*
C160.7361 (3)0.6288 (3)1.1612 (4)0.0395 (8)
H16A0.81210.68561.13450.059*
H16B0.78630.54501.19740.059*
H16C0.70340.66861.24560.059*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0401 (4)0.0234 (3)0.0606 (5)0.0026 (3)0.0209 (3)0.0072 (3)
Cl20.0418 (4)0.0447 (4)0.0518 (4)0.0023 (3)0.0313 (3)0.0049 (4)
O10.0303 (11)0.0442 (12)0.0622 (14)0.0111 (10)0.0081 (9)0.0002 (11)
C10.0221 (13)0.0210 (12)0.0259 (15)0.0004 (10)0.0077 (10)0.0016 (11)
C20.0249 (14)0.0268 (14)0.0358 (16)0.0033 (10)0.0153 (11)0.0027 (12)
C30.0240 (14)0.0314 (15)0.0292 (15)0.0012 (11)0.0093 (11)0.0024 (11)
C40.0246 (15)0.0439 (17)0.0376 (17)0.0060 (12)0.0046 (11)0.0013 (14)
C50.0207 (14)0.0578 (19)0.0425 (18)0.0052 (13)0.0044 (12)0.0043 (16)
C60.0323 (16)0.0418 (16)0.0368 (17)0.0130 (13)0.0126 (12)0.0085 (13)
C70.0290 (15)0.0355 (15)0.0319 (16)0.0079 (12)0.0146 (11)0.0076 (13)
C80.0224 (13)0.0252 (14)0.0273 (14)0.0002 (11)0.0084 (10)0.0021 (13)
C90.0299 (15)0.0271 (13)0.0277 (14)0.0078 (12)0.0119 (10)0.0036 (13)
C100.0274 (16)0.0276 (14)0.0301 (16)0.0066 (12)0.0073 (11)0.0058 (12)
C110.0249 (15)0.0258 (13)0.0362 (16)0.0015 (11)0.0100 (11)0.0087 (12)
C120.0279 (14)0.0232 (13)0.0333 (15)0.0039 (11)0.0121 (11)0.0018 (12)
C130.0425 (17)0.0523 (18)0.0275 (16)0.0021 (14)0.0105 (13)0.0078 (14)
C140.0409 (17)0.0547 (19)0.061 (2)0.0082 (16)0.0327 (15)0.0181 (18)
C150.0506 (19)0.0452 (18)0.0344 (17)0.0140 (15)0.0189 (13)0.0004 (15)
C160.0299 (16)0.0473 (19)0.0361 (17)0.0025 (12)0.0033 (12)0.0105 (14)
Geometric parameters (Å, º) top
Cl1—C21.764 (3)C8—C91.497 (3)
Cl2—C21.766 (3)C8—H81.0000
O1—C111.218 (3)C9—C101.336 (4)
C1—C21.509 (4)C9—H90.9500
C1—C121.519 (3)C10—C111.472 (4)
C1—C81.523 (4)C10—C161.505 (4)
C1—C31.526 (3)C11—C121.516 (4)
C2—C31.506 (4)C12—H12A0.9900
C3—C131.509 (4)C12—H12B0.9900
C3—C41.529 (4)C13—H13A0.9800
C4—C51.534 (4)C13—H13B0.9800
C4—H4A0.9900C13—H13C0.9800
C4—H4B0.9900C14—H14A0.9800
C5—C61.529 (4)C14—H14B0.9800
C5—H5A0.9900C14—H14C0.9800
C5—H5B0.9900C15—H15A0.9800
C6—C71.543 (4)C15—H15B0.9800
C6—H6A0.9900C15—H15C0.9800
C6—H6B0.9900C16—H16A0.9800
C7—C141.526 (4)C16—H16B0.9800
C7—C151.541 (4)C16—H16C0.9800
C7—C81.579 (4)
C2—C1—C12117.2 (2)C1—C8—C7115.1 (2)
C2—C1—C8119.0 (2)C9—C8—H8106.2
C12—C1—C8112.4 (2)C1—C8—H8106.2
C2—C1—C359.49 (16)C7—C8—H8106.2
C12—C1—C3121.2 (2)C10—C9—C8125.8 (2)
C8—C1—C3118.0 (2)C10—C9—H9117.1
C3—C2—C160.82 (17)C8—C9—H9117.1
C3—C2—Cl1121.74 (18)C9—C10—C11119.9 (2)
C1—C2—Cl1121.15 (19)C9—C10—C16122.9 (3)
C3—C2—Cl2119.2 (2)C11—C10—C16117.1 (2)
C1—C2—Cl2119.59 (18)O1—C11—C10121.7 (2)
Cl1—C2—Cl2108.11 (14)O1—C11—C12120.5 (2)
C2—C3—C13119.9 (2)C10—C11—C12117.7 (2)
C2—C3—C159.68 (17)C11—C12—C1111.6 (2)
C13—C3—C1120.9 (2)C11—C12—H12A109.3
C2—C3—C4117.6 (2)C1—C12—H12A109.3
C13—C3—C4113.3 (2)C11—C12—H12B109.3
C1—C3—C4115.6 (2)C1—C12—H12B109.3
C3—C4—C5111.3 (2)H12A—C12—H12B108.0
C3—C4—H4A109.4C3—C13—H13A109.5
C5—C4—H4A109.4C3—C13—H13B109.5
C3—C4—H4B109.4H13A—C13—H13B109.5
C5—C4—H4B109.4C3—C13—H13C109.5
H4A—C4—H4B108.0H13A—C13—H13C109.5
C6—C5—C4114.8 (2)H13B—C13—H13C109.5
C6—C5—H5A108.6C7—C14—H14A109.5
C4—C5—H5A108.6C7—C14—H14B109.5
C6—C5—H5B108.6H14A—C14—H14B109.5
C4—C5—H5B108.6C7—C14—H14C109.5
H5A—C5—H5B107.6H14A—C14—H14C109.5
C5—C6—C7118.0 (3)H14B—C14—H14C109.5
C5—C6—H6A107.8C7—C15—H15A109.5
C7—C6—H6A107.8C7—C15—H15B109.5
C5—C6—H6B107.8H15A—C15—H15B109.5
C7—C6—H6B107.8C7—C15—H15C109.5
H6A—C6—H6B107.1H15A—C15—H15C109.5
C14—C7—C15108.0 (2)H15B—C15—H15C109.5
C14—C7—C6109.7 (2)C10—C16—H16A109.5
C15—C7—C6106.7 (2)C10—C16—H16B109.5
C14—C7—C8108.2 (2)H16A—C16—H16B109.5
C15—C7—C8111.9 (2)C10—C16—H16C109.5
C6—C7—C8112.2 (2)H16A—C16—H16C109.5
C9—C8—C1110.0 (2)H16B—C16—H16C109.5
C9—C8—C7112.5 (2)

Experimental details

Crystal data
Chemical formulaC16H22Cl2O
Mr301.24
Crystal system, space groupMonoclinic, P21
Temperature (K)180
a, b, c (Å)8.8780 (3), 10.3340 (3), 8.9230 (3)
β (°) 108.805 (4)
V3)774.94 (4)
Z2
Radiation typeCu Kα
µ (mm1)3.67
Crystal size (mm)0.30 × 0.25 × 0.21
Data collection
DiffractometerAgilent Xcalibur (Eos, Gemini ultra)
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.761, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
2787, 1835, 1779
Rint0.027
θmax (°)60.6
(sin θ/λ)max1)0.565
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.028, 0.065, 1.03
No. of reflections1835
No. of parameters176
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.17
Absolute structureFlack & Bernardinelli (2000), 614 Friedel pairs
Absolute structure parameter0.014 (15)

Computer programs: CrysAlis PRO (Agilent, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009), WinGX (Farrugia, 2012).

 

References

First citationAgilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.
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