organic compounds
(1S,3R,8R,11S)-2,2-Dichloro-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-en-11-ol
aLaboratoire de Chimie Biomoléculaires, Substances Naturelles et Réactivité, URAC16, Faculté des Sciences, Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco, and bUniversité Blaise Pascal, Laboratoire des Matériaux Inorganiques, UMR CNRS 6002, 24 Avenue des Landais, 63177 Aubière, France
*Correspondence e-mail: elassaba@gmail.com
The title compound, C16H24Cl2O, was synthesized from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from essential oil of the Atlas cedar (Cedrus atlantica). The two fused rings exhibit different conformations: the six-membered ring has a screw-boat conformation, while the seven-membered ring displays a boat conformation. The dihedral angle between the two rings is 56.56 (18)°. In the crystal, molecules aggregate into supramolecular chains along the c axis mediated by O—H⋯O hydrogen bonds.
Related literature
For the isolation of β-himachalene, see: Joseph & Dev (1968); Plattier & Teisseire (1974). For the reactivity of this sesquiterpene, see: Lassaba et al. (1998); Chekroun et al. (2000); El Jamili et al. (2002); Sbai et al. (2002); Dakir et al. (2004). For its biological activity, see: Daoubi et al. (2004). For see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536811004788/tk2714sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811004788/tk2714Isup2.hkl
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) in 50 ml of 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. The reaction mixture was left stirring for 1 h, after which 20 ml of a
of NaHCO3 was added. Subsequently, the extraction was performed three times with diethyl ether (3 x 20 ml). The organic extracts were dried over Na2SO4, filtered, concentrated, and chromatographed. The title compound, (1S, 3R, 8R, 11S,)-2,2-dichloro-3,7,7,10-tetralethyltricyclo [6.4.0.01,3] dodec-9-by-11-ol was obtained with in a yield of 5% and was recrystallized its pentane solution.All H atoms were fixed geometrically and treated as riding with O—H = 0.82 Å and C—H = 0.93 (ethylene), 0.96 Å (methyl), 0.97 Å (methylene) and 0.98Å (methine), and with Uiso(H) = 1.2Ueq (ethylene, methylene, methine) or Uiso(H) = 1.5Ueq (O, methyl).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).C16H24Cl2O | Dx = 1.244 Mg m−3 |
Mr = 303.25 | Mo Kα radiation, λ = 0.71073 Å |
Trigonal, P32 | Cell parameters from 8123 reflections |
Hall symbol: P 32 | θ = 4–26.4° |
a = 13.2323 (13) Å | µ = 0.39 mm−1 |
c = 7.9807 (8) Å | T = 298 K |
V = 1210.2 (2) Å3 | Prism, colourless |
Z = 3 | 0.41 × 0.33 × 0.26 mm |
F(000) = 486 |
Bruker APEXII CCD diffractometer | 2995 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.019 |
Graphite monochromator | θmax = 26.4°, θmin = 4.0° |
ω and ϕ scans | h = −15→16 |
8123 measured reflections | k = −14→16 |
3135 independent reflections | l = −9→9 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.045 | H-atom parameters constrained |
wR(F2) = 0.126 | w = 1/[σ2(Fo2) + (0.0761P)2 + 0.4405P] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max < 0.001 |
3135 reflections | Δρmax = 0.52 e Å−3 |
180 parameters | Δρmin = −0.33 e Å−3 |
1 restraint | Absolute structure: Flack & Bernardinelli (2000), 1940 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.11 (7) |
C16H24Cl2O | Z = 3 |
Mr = 303.25 | Mo Kα radiation |
Trigonal, P32 | µ = 0.39 mm−1 |
a = 13.2323 (13) Å | T = 298 K |
c = 7.9807 (8) Å | 0.41 × 0.33 × 0.26 mm |
V = 1210.2 (2) Å3 |
Bruker APEXII CCD diffractometer | 2995 reflections with I > 2σ(I) |
8123 measured reflections | Rint = 0.019 |
3135 independent reflections |
R[F2 > 2σ(F2)] = 0.045 | H-atom parameters constrained |
wR(F2) = 0.126 | Δρmax = 0.52 e Å−3 |
S = 1.09 | Δρmin = −0.33 e Å−3 |
3135 reflections | Absolute structure: Flack & Bernardinelli (2000), 1940 Friedel pairs |
180 parameters | Absolute structure parameter: −0.11 (7) |
1 restraint |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 1.0043 (2) | 0.6432 (2) | 0.5388 (3) | 0.0304 (5) | |
C2 | 0.9057 (2) | 0.5880 (2) | 0.4113 (4) | 0.0370 (5) | |
C3 | 0.8790 (2) | 0.5564 (2) | 0.5938 (4) | 0.0392 (6) | |
C4 | 0.8143 (3) | 0.6069 (3) | 0.6915 (4) | 0.0464 (7) | |
H4A | 0.8228 | 0.6749 | 0.6329 | 0.056* | |
H4B | 0.7319 | 0.5493 | 0.6955 | 0.056* | |
C5 | 0.8600 (3) | 0.6411 (3) | 0.8682 (5) | 0.0541 (8) | |
H5A | 0.8234 | 0.5720 | 0.9384 | 0.065* | |
H5B | 0.8370 | 0.6953 | 0.9106 | 0.065* | |
C6 | 0.9973 (3) | 0.6991 (4) | 0.8854 (5) | 0.0591 (9) | |
H6A | 1.0178 | 0.7232 | 1.0010 | 0.071* | |
H6B | 1.0175 | 0.6394 | 0.8633 | 0.071* | |
C7 | 1.0733 (2) | 0.8032 (3) | 0.7746 (4) | 0.0426 (6) | |
C8 | 1.0545 (2) | 0.7728 (2) | 0.5810 (3) | 0.0308 (5) | |
H8 | 0.9966 | 0.7933 | 0.5426 | 0.041 (8)* | |
C9 | 1.1625 (2) | 0.8449 (2) | 0.4781 (4) | 0.0394 (6) | |
H9 | 1.1895 | 0.9246 | 0.4721 | 0.039 (8)* | |
C10 | 1.2228 (2) | 0.8058 (2) | 0.3951 (4) | 0.0367 (5) | |
C11 | 1.1869 (2) | 0.6778 (2) | 0.3958 (3) | 0.0333 (5) | |
H11 | 1.1523 | 0.6443 | 0.2867 | 0.029 (7)* | |
C12 | 1.0980 (2) | 0.6089 (2) | 0.5320 (4) | 0.0364 (5) | |
H12A | 1.0624 | 0.5260 | 0.5090 | 0.044* | |
H12B | 1.1371 | 0.6242 | 0.6396 | 0.044* | |
C13 | 1.3285 (3) | 0.8828 (3) | 0.2905 (5) | 0.0549 (8) | |
H13A | 1.3407 | 0.9607 | 0.2893 | 0.082* | |
H13B | 1.3164 | 0.8532 | 0.1780 | 0.082* | |
H13C | 1.3957 | 0.8837 | 0.3373 | 0.082* | |
C14 | 0.8465 (3) | 0.4338 (3) | 0.6503 (6) | 0.0633 (10) | |
H14A | 0.7653 | 0.3913 | 0.6796 | 0.095* | |
H14B | 0.8927 | 0.4386 | 0.7459 | 0.095* | |
H14C | 0.8611 | 0.3943 | 0.5608 | 0.095* | |
C15 | 1.0481 (4) | 0.9031 (4) | 0.8042 (6) | 0.0718 (11) | |
H15A | 0.9719 | 0.8811 | 0.7621 | 0.108* | |
H15B | 1.1055 | 0.9718 | 0.7469 | 0.108* | |
H15C | 1.0512 | 0.9188 | 0.9221 | 0.108* | |
C16 | 1.2019 (4) | 0.8507 (4) | 0.8255 (6) | 0.0730 (11) | |
H16A | 1.2122 | 0.8740 | 0.9410 | 0.109* | |
H16B | 1.2515 | 0.9168 | 0.7568 | 0.109* | |
H16C | 1.2219 | 0.7909 | 0.8102 | 0.109* | |
O1 | 1.28683 (18) | 0.6633 (2) | 0.4212 (3) | 0.0453 (5) | |
H1 | 1.3211 | 0.6727 | 0.3319 | 0.068* | |
Cl1 | 0.85533 (6) | 0.67322 (7) | 0.30875 (9) | 0.0497 (2) | |
Cl2 | 0.90015 (7) | 0.48357 (7) | 0.26866 (11) | 0.0605 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0314 (11) | 0.0304 (11) | 0.0315 (12) | 0.0170 (10) | 0.0015 (9) | 0.0018 (9) |
C2 | 0.0353 (12) | 0.0343 (12) | 0.0391 (14) | 0.0157 (10) | −0.0032 (10) | −0.0049 (10) |
C3 | 0.0350 (13) | 0.0374 (13) | 0.0431 (15) | 0.0164 (11) | 0.0042 (11) | 0.0079 (11) |
C4 | 0.0365 (14) | 0.0604 (18) | 0.0436 (16) | 0.0253 (13) | 0.0107 (11) | 0.0114 (13) |
C5 | 0.0556 (19) | 0.069 (2) | 0.0418 (16) | 0.0344 (17) | 0.0144 (14) | 0.0117 (15) |
C6 | 0.065 (2) | 0.079 (2) | 0.0401 (17) | 0.0407 (19) | −0.0012 (14) | 0.0047 (16) |
C7 | 0.0435 (14) | 0.0539 (16) | 0.0364 (14) | 0.0289 (13) | −0.0053 (11) | −0.0123 (12) |
C8 | 0.0306 (11) | 0.0319 (12) | 0.0351 (12) | 0.0197 (10) | 0.0012 (9) | −0.0015 (9) |
C9 | 0.0409 (14) | 0.0287 (12) | 0.0461 (16) | 0.0155 (10) | 0.0048 (11) | 0.0006 (10) |
C10 | 0.0320 (12) | 0.0339 (13) | 0.0409 (14) | 0.0141 (10) | 0.0025 (10) | −0.0003 (10) |
C11 | 0.0327 (12) | 0.0367 (12) | 0.0365 (14) | 0.0218 (10) | −0.0017 (9) | −0.0045 (10) |
C12 | 0.0369 (12) | 0.0343 (12) | 0.0451 (14) | 0.0230 (11) | 0.0031 (10) | 0.0023 (10) |
C13 | 0.0452 (16) | 0.0493 (17) | 0.064 (2) | 0.0190 (14) | 0.0200 (15) | 0.0072 (14) |
C14 | 0.0562 (19) | 0.0404 (16) | 0.082 (3) | 0.0158 (15) | 0.0123 (17) | 0.0191 (16) |
C15 | 0.078 (3) | 0.071 (2) | 0.078 (3) | 0.046 (2) | 0.002 (2) | −0.023 (2) |
C16 | 0.058 (2) | 0.087 (3) | 0.069 (3) | 0.033 (2) | −0.0150 (19) | −0.023 (2) |
O1 | 0.0410 (10) | 0.0614 (13) | 0.0479 (12) | 0.0365 (10) | 0.0009 (8) | −0.0025 (9) |
Cl1 | 0.0471 (4) | 0.0680 (5) | 0.0384 (3) | 0.0321 (4) | −0.0065 (3) | 0.0047 (3) |
Cl2 | 0.0541 (4) | 0.0536 (4) | 0.0643 (5) | 0.0199 (4) | −0.0071 (4) | −0.0266 (4) |
C1—C12 | 1.521 (3) | C9—C10 | 1.326 (4) |
C1—C2 | 1.522 (3) | C9—H9 | 0.9300 |
C1—C3 | 1.534 (3) | C10—C13 | 1.506 (4) |
C1—C8 | 1.535 (3) | C10—C11 | 1.513 (4) |
C2—C3 | 1.507 (4) | C11—O1 | 1.442 (3) |
C2—Cl2 | 1.764 (3) | C11—C12 | 1.524 (4) |
C2—Cl1 | 1.771 (3) | C11—H11 | 0.9800 |
C3—C14 | 1.524 (4) | C12—H12A | 0.9700 |
C3—C4 | 1.535 (4) | C12—H12B | 0.9700 |
C4—C5 | 1.512 (5) | C13—H13A | 0.9600 |
C4—H4A | 0.9700 | C13—H13B | 0.9600 |
C4—H4B | 0.9700 | C13—H13C | 0.9600 |
C5—C6 | 1.584 (5) | C14—H14A | 0.9600 |
C5—H5A | 0.9700 | C14—H14B | 0.9600 |
C5—H5B | 0.9700 | C14—H14C | 0.9600 |
C6—C7 | 1.518 (5) | C15—H15A | 0.9600 |
C6—H6A | 0.9700 | C15—H15B | 0.9600 |
C6—H6B | 0.9700 | C15—H15C | 0.9600 |
C7—C15 | 1.534 (5) | C16—H16A | 0.9600 |
C7—C16 | 1.545 (5) | C16—H16B | 0.9600 |
C7—C8 | 1.585 (4) | C16—H16C | 0.9600 |
C8—C9 | 1.505 (3) | O1—H1 | 0.8200 |
C8—H8 | 0.9800 | ||
C12—C1—C2 | 117.7 (2) | C1—C8—H8 | 106.2 |
C12—C1—C3 | 121.6 (2) | C7—C8—H8 | 106.2 |
C2—C1—C3 | 59.08 (17) | C10—C9—C8 | 126.2 (2) |
C12—C1—C8 | 112.3 (2) | C10—C9—H9 | 116.9 |
C2—C1—C8 | 118.1 (2) | C8—C9—H9 | 116.9 |
C3—C1—C8 | 118.4 (2) | C9—C10—C13 | 123.3 (3) |
C3—C2—C1 | 60.86 (17) | C9—C10—C11 | 121.5 (2) |
C3—C2—Cl2 | 119.6 (2) | C13—C10—C11 | 115.2 (2) |
C1—C2—Cl2 | 119.77 (19) | O1—C11—C10 | 110.7 (2) |
C3—C2—Cl1 | 120.9 (2) | O1—C11—C12 | 107.7 (2) |
C1—C2—Cl1 | 120.59 (18) | C10—C11—C12 | 112.9 (2) |
Cl2—C2—Cl1 | 108.61 (15) | O1—C11—H11 | 108.5 |
C2—C3—C14 | 118.9 (3) | C10—C11—H11 | 108.5 |
C2—C3—C1 | 60.06 (16) | C12—C11—H11 | 108.5 |
C14—C3—C1 | 120.3 (3) | C1—C12—C11 | 110.3 (2) |
C2—C3—C4 | 118.3 (2) | C1—C12—H12A | 109.6 |
C14—C3—C4 | 113.0 (3) | C11—C12—H12A | 109.6 |
C1—C3—C4 | 116.7 (2) | C1—C12—H12B | 109.6 |
C5—C4—C3 | 112.2 (3) | C11—C12—H12B | 109.6 |
C5—C4—H4A | 109.2 | H12A—C12—H12B | 108.1 |
C3—C4—H4A | 109.2 | C10—C13—H13A | 109.5 |
C5—C4—H4B | 109.2 | C10—C13—H13B | 109.5 |
C3—C4—H4B | 109.2 | H13A—C13—H13B | 109.5 |
H4A—C4—H4B | 107.9 | C10—C13—H13C | 109.5 |
C4—C5—C6 | 114.6 (3) | H13A—C13—H13C | 109.5 |
C4—C5—H5A | 108.6 | H13B—C13—H13C | 109.5 |
C6—C5—H5A | 108.6 | C3—C14—H14A | 109.5 |
C4—C5—H5B | 108.6 | C3—C14—H14B | 109.5 |
C6—C5—H5B | 108.6 | H14A—C14—H14B | 109.5 |
H5A—C5—H5B | 107.6 | C3—C14—H14C | 109.5 |
C7—C6—C5 | 118.0 (3) | H14A—C14—H14C | 109.5 |
C7—C6—H6A | 107.8 | H14B—C14—H14C | 109.5 |
C5—C6—H6A | 107.8 | C7—C15—H15A | 109.5 |
C7—C6—H6B | 107.8 | C7—C15—H15B | 109.5 |
C5—C6—H6B | 107.8 | H15A—C15—H15B | 109.5 |
H6A—C6—H6B | 107.2 | C7—C15—H15C | 109.5 |
C6—C7—C15 | 111.2 (3) | H15A—C15—H15C | 109.5 |
C6—C7—C16 | 108.2 (3) | H15B—C15—H15C | 109.5 |
C15—C7—C16 | 106.2 (3) | C7—C16—H16A | 109.5 |
C6—C7—C8 | 112.8 (2) | C7—C16—H16B | 109.5 |
C15—C7—C8 | 107.1 (3) | H16A—C16—H16B | 109.5 |
C16—C7—C8 | 111.1 (3) | C7—C16—H16C | 109.5 |
C9—C8—C1 | 109.4 (2) | H16A—C16—H16C | 109.5 |
C9—C8—C7 | 113.1 (2) | H16B—C16—H16C | 109.5 |
C1—C8—C7 | 115.0 (2) | C11—O1—H1 | 109.5 |
C9—C8—H8 | 106.2 |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O1i | 0.82 | 2.10 | 2.853 (4) | 153 |
Symmetry code: (i) −y+2, x−y, z−1/3. |
Experimental details
Crystal data | |
Chemical formula | C16H24Cl2O |
Mr | 303.25 |
Crystal system, space group | Trigonal, P32 |
Temperature (K) | 298 |
a, c (Å) | 13.2323 (13), 7.9807 (8) |
V (Å3) | 1210.2 (2) |
Z | 3 |
Radiation type | Mo Kα |
µ (mm−1) | 0.39 |
Crystal size (mm) | 0.41 × 0.33 × 0.26 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8123, 3135, 2995 |
Rint | 0.019 |
(sin θ/λ)max (Å−1) | 0.625 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.126, 1.09 |
No. of reflections | 3135 |
No. of parameters | 180 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.52, −0.33 |
Absolute structure | Flack & Bernardinelli (2000), 1940 Friedel pairs |
Absolute structure parameter | −0.11 (7) |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O1i | 0.820 | 2.10 | 2.853 (4) | 153 |
Symmetry code: (i) −y+2, x−y, z−1/3. |
Acknowledgements
We thank the National Center of Scientific and Technological Research (CNRST) which supports our scientific research.
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The bicyclic sesquiterpene β-himachalene is the main constituent of the essential oil of the Atlas cedar (Cedrus atlantica) (Joseph & Dev, 1968; Plattier & Teisseire, 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; Sbai et al., 2002; Dakir et al., 2004). Indeed, these compounds were tested, using the food poisoning technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea (Daoubi et al., 2004).
The action of one equivalent of dichlorocarbene, generated in situ from chloroform in the presence of sodium hydroxide as base and n-benzyltriethylammonium chloride as catalyst, on β-himachalene produces only (1S,3R,8R)-2,2-dichloro-3,7,7,10- tetramethyltricyclo[6.4.0.01,3]dodec-9-ene (El Jamili et al., 2002). Treatment of the latter compound with two equivalents of N-bromosuccinimide gives (1S, 3R, 8R, 11S)-2,2-dichloro -3,7,7,10-tetralethyltricyclo[6.4.0.01,3]dodec-9-en-11-ol in a very low yield (5%), along with other products. The structure of this new product was determined by NMR (1H & 13C) spectral analysis and mass spectroscopy, and confirmed by a crystallographic study, reported herein.
The molecule is built up from two fused six-membered and seven-membered rings (Fig. 1). The six-membered ring has a screw boat conformation, as indicated by the total puckering amplitude QT = 0.480 (3) Å and spherical polar angle θ = 130.6 (4) ° with ϕ = 151.5 (5) °, whereas the seven-membered ring displays a boat conformation with QT = 1.1449 (30) Å, θ2 = 88.29 (15) °, ϕ2 = -47.13 (14) ° and ϕ3 =-144.24 (5) ° (Cremer & Pople, 1975). In the crystal structure, molecules are linked into supramolecular chains (Fig. 2) running along the c axis by O—H···O hydrogen bonds (Table 1). Owing to the presence of Cl atoms, the absolute configuration could be fully confirmed, as C1(S), C3(R), C8(R) and C11(S).