organic compounds
(1S,3R,8R)-2,2-Dibromo-10-bromomethyl-3,7,7-trimethyltricyclo[6.4.0.01,3]dodec-9-ene
aLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco, bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Avenue Ibn Battouta, BP 1014 Rabat, Morocco, and cLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: berraho@uca.ma
The title compound, C16H23Br3, 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 from the reaction of himachalene with dibromocarbene. The six-membered ring has an (the flap atom being the C atom shared with the three-membered ring, whereas the seven-membered ring displays a screw boat conformation; the dihedral angle between the rings (defined by the near coplanar atoms) is 56.5 (2)°.
Related literature
For the isolation of β-himachalene, see: Joseph & Dev (1968); Plattier & Teiseire (1974). For the reactivity of this sesquiterpene, see: Lassaba et al. (1997); Chekroun et al. (2000); El Jamili et al. (2002); Sbai et al. (2002); Dakir et al. (2004); Benharref et al. (2010). For its biological activity, see: Daoubi et al. (2004). For see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection: CrysAlis PRO (Agilent, 2010); cell CrysAlis PRO; data reduction: CrysAlis PRO; 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); software used to prepare material for publication: WinGX (Farrugia, 2012).
Supporting information
10.1107/S1600536812046430/im2411sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812046430/im2411Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812046430/im2411Isup3.cml
In a reactor containing a solution of (1S,3R,8R)-2,2-dibromo-3,7,7,10 tetramethyltricyclo[6.4.0.01,3] dodec-9-ene (1 g, 2.6 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 g (5.2 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)-2,2,16-tribromo-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-ene was obtained with a yield of 16% (18 mg, 0.4 mmol) and was recrystallized from n-pentane solution at room temperature.All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.97 Å (methylene) and 0.98 Å (methine) with Uiso(H) = 1.2 Ueq(methylene, methine) or Uiso(H) = 1.5 Ueq(methyl).
Data collection: CrysAlis PRO (Agilent, 2010); cell
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); software used to prepare material for publication: WinGX (Farrugia, 2012).Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii. |
C16H23Br3 | F(000) = 896 |
Mr = 455.07 | Dx = 1.768 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 3461 reflections |
a = 9.2614 (5) Å | θ = 3.1–26.4° |
b = 12.8215 (8) Å | µ = 7.07 mm−1 |
c = 14.3966 (11) Å | T = 180 K |
V = 1709.52 (19) Å3 | Prism, colourless |
Z = 4 | 0.49 × 0.31 × 0.08 mm |
Agilent Xcalibur (Sapphire1, long nozzle) diffractometer | 3461 independent reflections |
Graphite monochromator | 3121 reflections with I > 2σ(I) |
Detector resolution: 8.2632 pixels mm-1 | Rint = 0.049 |
ω scans | θmax = 26.4°, θmin = 3.1° |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010) | h = −11→11 |
Tmin = 0.135, Tmax = 1.000 | k = −16→15 |
9721 measured reflections | l = −15→17 |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.034 | w = 1/[σ2(Fo2) + (0.0387P)2 + 0.0947P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.075 | (Δ/σ)max = 0.001 |
S = 1.04 | Δρmax = 0.66 e Å−3 |
3461 reflections | Δρmin = −0.55 e Å−3 |
176 parameters | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
0 restraints | Extinction coefficient: 0.0034 (4) |
Primary atom site location: structure-invariant direct methods | Absolute structure: Flack (1983), 1460 Friedel pairs |
Secondary atom site location: difference Fourier map | Absolute structure parameter: 0.012 (16) |
C16H23Br3 | V = 1709.52 (19) Å3 |
Mr = 455.07 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 9.2614 (5) Å | µ = 7.07 mm−1 |
b = 12.8215 (8) Å | T = 180 K |
c = 14.3966 (11) Å | 0.49 × 0.31 × 0.08 mm |
Agilent Xcalibur (Sapphire1, long nozzle) diffractometer | 3461 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010) | 3121 reflections with I > 2σ(I) |
Tmin = 0.135, Tmax = 1.000 | Rint = 0.049 |
9721 measured reflections |
R[F2 > 2σ(F2)] = 0.034 | H-atom parameters constrained |
wR(F2) = 0.075 | Δρmax = 0.66 e Å−3 |
S = 1.04 | Δρmin = −0.55 e Å−3 |
3461 reflections | Absolute structure: Flack (1983), 1460 Friedel pairs |
176 parameters | Absolute structure parameter: 0.012 (16) |
0 restraints |
Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. CrysAlisPro (Agilent, 2010) |
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. |
x | y | z | Uiso*/Ueq | ||
C13 | 0.9676 (5) | 0.5913 (4) | 0.4115 (3) | 0.0283 (12) | |
H13A | 0.9119 | 0.6220 | 0.4606 | 0.042* | |
H13B | 0.9989 | 0.5230 | 0.4299 | 0.042* | |
H13C | 0.9093 | 0.5861 | 0.3565 | 0.042* | |
C1 | 1.1613 (4) | 0.6641 (3) | 0.2929 (3) | 0.0110 (8) | |
C2 | 1.0820 (5) | 0.7571 (3) | 0.3330 (3) | 0.0164 (9) | |
C3 | 1.0980 (5) | 0.6589 (3) | 0.3916 (3) | 0.0160 (9) | |
C4 | 1.2066 (6) | 0.6600 (3) | 0.4707 (3) | 0.0251 (11) | |
H4A | 1.1567 | 0.6746 | 0.5285 | 0.030* | |
H4B | 1.2760 | 0.7154 | 0.4602 | 0.030* | |
C5 | 1.2867 (6) | 0.5560 (4) | 0.4793 (3) | 0.0280 (12) | |
H5A | 1.2275 | 0.5082 | 0.5151 | 0.034* | |
H5B | 1.3752 | 0.5675 | 0.5139 | 0.034* | |
C6 | 1.3251 (5) | 0.5037 (3) | 0.3864 (3) | 0.0233 (10) | |
H6A | 1.2356 | 0.4818 | 0.3573 | 0.028* | |
H6B | 1.3798 | 0.4410 | 0.4001 | 0.028* | |
C7 | 1.4112 (5) | 0.5671 (3) | 0.3143 (3) | 0.0196 (10) | |
C8 | 1.3273 (4) | 0.6703 (3) | 0.2837 (3) | 0.0146 (8) | |
H8 | 1.3594 | 0.7261 | 0.3254 | 0.018* | |
C9 | 1.3668 (4) | 0.7037 (3) | 0.1861 (3) | 0.0186 (10) | |
H9 | 1.4614 | 0.7250 | 0.1756 | 0.022* | |
C10 | 1.2776 (5) | 0.7050 (3) | 0.1147 (3) | 0.0158 (9) | |
C11 | 1.1229 (5) | 0.6707 (3) | 0.1223 (3) | 0.0161 (9) | |
H11A | 1.0988 | 0.6284 | 0.0687 | 0.019* | |
H11B | 1.0611 | 0.7318 | 0.1214 | 0.019* | |
C12 | 1.0923 (4) | 0.6086 (3) | 0.2101 (3) | 0.0139 (8) | |
H12A | 1.1318 | 0.5389 | 0.2041 | 0.017* | |
H12B | 0.9889 | 0.6028 | 0.2195 | 0.017* | |
C14 | 1.5566 (5) | 0.6008 (4) | 0.3559 (4) | 0.0427 (15) | |
H14A | 1.6119 | 0.5401 | 0.3719 | 0.064* | |
H14B | 1.5400 | 0.6419 | 0.4106 | 0.064* | |
H14C | 1.6088 | 0.6415 | 0.3111 | 0.064* | |
C15 | 1.4416 (6) | 0.4939 (4) | 0.2310 (3) | 0.0328 (13) | |
H15A | 1.4933 | 0.4336 | 0.2521 | 0.049* | |
H15B | 1.4985 | 0.5303 | 0.1856 | 0.049* | |
H15C | 1.3518 | 0.4727 | 0.2036 | 0.049* | |
C16 | 1.3330 (6) | 0.7378 (4) | 0.0200 (3) | 0.0286 (11) | |
H16A | 1.3172 | 0.6817 | −0.0241 | 0.034* | |
H16B | 1.4361 | 0.7506 | 0.0236 | 0.034* | |
Br1 | 0.89111 (5) | 0.79294 (4) | 0.28578 (3) | 0.02481 (13) | |
Br2 | 1.17768 (6) | 0.88596 (3) | 0.36490 (3) | 0.02729 (14) | |
Br3 | 1.23443 (7) | 0.86490 (4) | −0.02407 (4) | 0.04212 (18) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C13 | 0.030 (3) | 0.028 (3) | 0.027 (3) | −0.002 (2) | 0.016 (2) | 0.009 (2) |
C1 | 0.0118 (18) | 0.0124 (18) | 0.0088 (19) | −0.0009 (16) | 0.0025 (16) | 0.0028 (17) |
C2 | 0.016 (2) | 0.018 (2) | 0.015 (2) | −0.0061 (18) | 0.0004 (17) | −0.0025 (18) |
C3 | 0.020 (2) | 0.015 (2) | 0.013 (2) | 0.0007 (19) | 0.0037 (18) | −0.0005 (17) |
C4 | 0.047 (3) | 0.021 (2) | 0.007 (2) | 0.003 (2) | −0.005 (2) | −0.0004 (18) |
C5 | 0.046 (3) | 0.026 (2) | 0.013 (2) | 0.008 (2) | −0.005 (2) | 0.004 (2) |
C6 | 0.032 (3) | 0.019 (2) | 0.020 (3) | 0.007 (2) | −0.001 (2) | 0.0051 (18) |
C7 | 0.012 (2) | 0.021 (2) | 0.026 (3) | 0.0040 (19) | −0.0045 (18) | 0.0045 (19) |
C8 | 0.0139 (19) | 0.015 (2) | 0.015 (2) | −0.0022 (17) | −0.0019 (19) | 0.0036 (18) |
C9 | 0.010 (2) | 0.019 (2) | 0.026 (3) | −0.0017 (18) | 0.0026 (16) | 0.007 (2) |
C10 | 0.021 (2) | 0.0145 (19) | 0.012 (2) | 0.0047 (19) | 0.0061 (17) | 0.0031 (17) |
C11 | 0.020 (2) | 0.018 (2) | 0.010 (2) | −0.0006 (18) | −0.0006 (17) | −0.0011 (17) |
C12 | 0.0130 (19) | 0.0158 (19) | 0.013 (2) | 0.0010 (18) | 0.0010 (18) | −0.0032 (18) |
C14 | 0.020 (3) | 0.042 (3) | 0.066 (4) | −0.003 (2) | −0.022 (3) | 0.018 (3) |
C15 | 0.029 (3) | 0.030 (3) | 0.040 (3) | 0.015 (2) | 0.009 (2) | 0.010 (2) |
C16 | 0.033 (3) | 0.030 (3) | 0.023 (3) | 0.010 (2) | 0.011 (2) | 0.012 (2) |
Br1 | 0.0178 (2) | 0.0254 (2) | 0.0312 (3) | 0.0070 (2) | 0.0019 (2) | −0.0009 (2) |
Br2 | 0.0377 (3) | 0.0147 (2) | 0.0295 (3) | −0.0026 (2) | −0.0072 (2) | −0.0044 (2) |
Br3 | 0.0431 (3) | 0.0365 (3) | 0.0467 (4) | 0.0046 (3) | 0.0065 (3) | 0.0243 (3) |
C13—C3 | 1.514 (6) | C7—C15 | 1.549 (6) |
C13—H13A | 0.9600 | C7—C8 | 1.596 (6) |
C13—H13B | 0.9600 | C8—C9 | 1.515 (6) |
C13—H13C | 0.9600 | C8—H8 | 0.9800 |
C1—C2 | 1.516 (6) | C9—C10 | 1.318 (6) |
C1—C12 | 1.528 (5) | C9—H9 | 0.9300 |
C1—C3 | 1.540 (6) | C10—C11 | 1.503 (6) |
C1—C8 | 1.544 (5) | C10—C16 | 1.517 (6) |
C2—C3 | 1.523 (6) | C11—C12 | 1.520 (6) |
C2—Br2 | 1.930 (4) | C11—H11A | 0.9700 |
C2—Br1 | 1.949 (4) | C11—H11B | 0.9700 |
C3—C4 | 1.519 (6) | C12—H12A | 0.9700 |
C4—C5 | 1.532 (6) | C12—H12B | 0.9700 |
C4—H4A | 0.9700 | C14—H14A | 0.9600 |
C4—H4B | 0.9700 | C14—H14B | 0.9600 |
C5—C6 | 1.538 (6) | C14—H14C | 0.9600 |
C5—H5A | 0.9700 | C15—H15A | 0.9600 |
C5—H5B | 0.9700 | C15—H15B | 0.9600 |
C6—C7 | 1.541 (6) | C15—H15C | 0.9600 |
C6—H6A | 0.9700 | C16—Br3 | 1.973 (4) |
C6—H6B | 0.9700 | C16—H16A | 0.9700 |
C7—C14 | 1.535 (6) | C16—H16B | 0.9700 |
C3—C13—H13A | 109.5 | C14—C7—C8 | 107.5 (4) |
C3—C13—H13B | 109.5 | C6—C7—C8 | 111.8 (3) |
H13A—C13—H13B | 109.5 | C15—C7—C8 | 112.1 (4) |
C3—C13—H13C | 109.5 | C9—C8—C1 | 109.5 (3) |
H13A—C13—H13C | 109.5 | C9—C8—C7 | 111.9 (3) |
H13B—C13—H13C | 109.5 | C1—C8—C7 | 114.7 (3) |
C2—C1—C12 | 117.5 (3) | C9—C8—H8 | 106.7 |
C2—C1—C3 | 59.8 (3) | C1—C8—H8 | 106.7 |
C12—C1—C3 | 122.7 (3) | C7—C8—H8 | 106.7 |
C2—C1—C8 | 118.3 (4) | C10—C9—C8 | 125.1 (4) |
C12—C1—C8 | 112.0 (3) | C10—C9—H9 | 117.4 |
C3—C1—C8 | 117.4 (4) | C8—C9—H9 | 117.4 |
C1—C2—C3 | 60.9 (3) | C9—C10—C11 | 122.5 (4) |
C1—C2—Br2 | 122.8 (3) | C9—C10—C16 | 119.5 (4) |
C3—C2—Br2 | 122.1 (3) | C11—C10—C16 | 118.0 (4) |
C1—C2—Br1 | 119.5 (3) | C10—C11—C12 | 113.0 (3) |
C3—C2—Br1 | 118.5 (3) | C10—C11—H11A | 109.0 |
Br2—C2—Br1 | 107.3 (2) | C12—C11—H11A | 109.0 |
C13—C3—C4 | 113.1 (4) | C10—C11—H11B | 109.0 |
C13—C3—C2 | 120.0 (4) | C12—C11—H11B | 109.0 |
C4—C3—C2 | 118.1 (4) | H11A—C11—H11B | 107.8 |
C13—C3—C1 | 120.2 (4) | C11—C12—C1 | 109.1 (3) |
C4—C3—C1 | 116.1 (4) | C11—C12—H12A | 109.9 |
C2—C3—C1 | 59.3 (3) | C1—C12—H12A | 109.9 |
C3—C4—C5 | 111.9 (4) | C11—C12—H12B | 109.9 |
C3—C4—H4A | 109.2 | C1—C12—H12B | 109.9 |
C5—C4—H4A | 109.2 | H12A—C12—H12B | 108.3 |
C3—C4—H4B | 109.2 | C7—C14—H14A | 109.5 |
C5—C4—H4B | 109.2 | C7—C14—H14B | 109.5 |
H4A—C4—H4B | 107.9 | H14A—C14—H14B | 109.5 |
C4—C5—C6 | 114.9 (4) | C7—C14—H14C | 109.5 |
C4—C5—H5A | 108.5 | H14A—C14—H14C | 109.5 |
C6—C5—H5A | 108.5 | H14B—C14—H14C | 109.5 |
C4—C5—H5B | 108.5 | C7—C15—H15A | 109.5 |
C6—C5—H5B | 108.5 | C7—C15—H15B | 109.5 |
H5A—C5—H5B | 107.5 | H15A—C15—H15B | 109.5 |
C5—C6—C7 | 118.4 (4) | C7—C15—H15C | 109.5 |
C5—C6—H6A | 107.7 | H15A—C15—H15C | 109.5 |
C7—C6—H6A | 107.7 | H15B—C15—H15C | 109.5 |
C5—C6—H6B | 107.7 | C10—C16—Br3 | 111.2 (3) |
C7—C6—H6B | 107.7 | C10—C16—H16A | 109.4 |
H6A—C6—H6B | 107.1 | Br3—C16—H16A | 109.4 |
C14—C7—C6 | 109.9 (4) | C10—C16—H16B | 109.4 |
C14—C7—C15 | 108.2 (4) | Br3—C16—H16B | 109.4 |
C6—C7—C15 | 107.2 (4) | H16A—C16—H16B | 108.0 |
Experimental details
Crystal data | |
Chemical formula | C16H23Br3 |
Mr | 455.07 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 180 |
a, b, c (Å) | 9.2614 (5), 12.8215 (8), 14.3966 (11) |
V (Å3) | 1709.52 (19) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 7.07 |
Crystal size (mm) | 0.49 × 0.31 × 0.08 |
Data collection | |
Diffractometer | Agilent Xcalibur (Sapphire1, long nozzle) diffractometer |
Absorption correction | Multi-scan (CrysAlis PRO; Agilent, 2010) |
Tmin, Tmax | 0.135, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9721, 3461, 3121 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.625 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.034, 0.075, 1.04 |
No. of reflections | 3461 |
No. of parameters | 176 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.66, −0.55 |
Absolute structure | Flack (1983), 1460 Friedel pairs |
Absolute structure parameter | 0.012 (16) |
Computer programs: CrysAlis PRO (Agilent, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).
Acknowledgements
The authors thank the Unit of Support for Technical and Scientific Research (UATRS and CNRST) for the X-ray measurements.
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Our work lies within the framework of the valorization of the most abundant essential oils in Morocco, such as the one from Cedrus atlantica. This oil is made up mainly (75%) of bicyclic sesquiterpenes hydrocarbons, among which is found β-himachalene (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., 1997; Chekroun et al., 2000; El Jamili et al., 2002; Sbai et al., 2002; Dakir et al., 2004; Benharref et al.,2010). Indeed, these compounds were tested, using the food poisoning technique, for their potential antifungal activity against the phytopathogen Botrytis cinerea (Daoubi et al., 2004). In a previous work (El Jamili et al., 2002) we have prepared (1S,3R,8R)-2,2-dibromo- 3,7,7,10- tetramethyltricyclo [6.4.0.01,3] dodec-9-ene from β-himachalene, which by treatment with N-bromosuccinimide gave the title compound. The structure of this new product was determined by single-crystal X-ray structure analysis. 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 = 0.497 (4) Å and spherical polar angle θ= 129.5 (5)° with ϕ = 149.2 (7)°, whereas the seven-membered ring displays a screw boat conformation with QT = 1.1556 (4) Å, θ = 88.2 (20)°, ϕ2 = -48.26 (20)° and ϕ3 = -117.47 (7)° (Cremer & Pople, 1975). Owing to the presence of Br atoms, the absolute configuration could be fully confirmed as C1(S), C3(R)and C8(R) by refining the Flack (1983) parameter as C1(S), C3(R)and C8(R).