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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 69| Part 11| November 2013| Pages o1692-o1693

Absolute configuration of (1S,3R,8R)-10-bromo­methyl-2,2-di­chloro-3,7,7-tri­methyl­tri­cyclo­[6.4.0.01,3]dodec-9-ene

aLaboratoire de Physico-Chimie Moléculaire et Synthése Organique, Département de Chimie Faculté des Sciences, Semlalia BP 2390, Marrakech 40001, Morocco, and bLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: itto35@hotmail.com

(Received 24 September 2013; accepted 14 October 2013; online 23 October 2013)

The absolute configuration of the title compound, C16H23BrCl2, has been deduced from the chemical pathway and fully confirmed by refinement of the Flack and Hooft parameters. The six-membered ring adopts a half-chair conformation, whereas the seven-membered ring is a twisted chair. The mol­ecular packing within the crystal is stabilized only by van der Waals inter­actions.

Related literature

For the synthesis of the title compound, 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 further synthetic details, see: Qu et al. (2009[Qu, J.-P., Deng, C., Zhou, J., Sun, X.-L. & Tang, Y. (2009). J. Org. Chem. 74, 7684-7689.]). For biological properties of cyclo­propane-containing products, see: Ajay Kumar et al. (2012[Ajay Kumar, K., Lokanatha Rai, K. M., Vasanth Kumar, G. & Mylarappa, B. N. (2012). Int. J. Pharm. Pharm. Sci. 4, Suppl. 4, 564-568.]); Sow et al. (2007[Sow, G. J., Ndams, I. S., Kogi, E., Tukur, Z. & Adamu, H. (2007). Sci. World J. 2, 5-8.]); Symon et al. (2005[Symon, A. V., Veselova, N. N., Kaplun, A. P., Vlasenkova, N. K., Fedorova, G. A., Liutik, A. I., Gerasimova, G. K. & Shvets, V. I. (2005). Russ. J. Bioorg. Chem. 31, 320-325.]). For related structures, see: Benharref et al. (2010[Benharref, A., El Ammari, L., Berraho, M. & Lassaba, E. (2010). Acta Cryst. E66, o2463.]); Gassman & Gorman (1990[Gassman, P. G. & Gorman, D. B. (1990). J. Am. Chem. Soc. 112, 8624-8626.]); Lassaba et al. (1997[Lassaba, E., Benharref, A., Giorgi, M. & Pierrot, M. (1997). Acta Cryst. C53, 1943-1945.]). For conformations of rings, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Boessenkool & Boyens (1980[Boessenkool, I. K. & Boyens, J. C. A. (1980). J. Cryst. Mol. Struct. 10, 11-18.]); For absolute structure, see: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]); Flack & Bernardinelli (2000[Flack, H. D. & Bernardinelli, G. (2000). J. Appl. Cryst. 33, 1143-1148.]); Spek (2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

[Scheme 1]

Experimental

Crystal data
  • C16H23BrCl2

  • Mr = 366.15

  • Orthorhombic, P 21 21 21

  • a = 9.1000 (2) Å

  • b = 12.5490 (4) Å

  • c = 14.4070 (5) Å

  • V = 1645.22 (9) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 6.26 mm−1

  • T = 173 K

  • 0.45 × 0.25 × 0.10 mm

Data collection
  • Agilent Xcalibur Gemini ultra diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012[Agilent (2012). CrysAlis PRO Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.397, Tmax = 1.000

  • 9248 measured reflections

  • 3127 independent reflections

  • 3012 reflections with I > 2σ(I)

  • Rint = 0.038

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.070

  • S = 1.04

  • 3127 reflections

  • 176 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.46 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1307 Friedel pairs

  • Absolute structure parameter: −0.015 (17)

Data collection: CrysAlis PRO (Agilent, 2012[Agilent (2012). CrysAlis PRO Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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: SHELXL97.

Supporting information


Comment top

Cyclopropane-containing natural products attract great interest because of their biological properties ranging from insecticidal (Sow et al., 2007) and antimicrobial (Ajay Kumar et al., 2012) to antitumoral activities (Symon et al., 2005). They are also valuable intermediates and are frequently used as versatile building blocks in organic synthesis (Qu et al., 2009).

In our ongoing studies on the synthesis of new chiral sesquiterpenic cyclopropanes, we carried out the reaction of (1S,3R,8R)-2,2-dichloro-3,7,7-10-tetramethyltricyclo[6.4.0.01,3]dodec-9-ene (El Jamili et al., 2002) with N-bromosuccinimide (NBS) and obtained the title compound in poor yield. Its gross structure was confirmed by spectroscopic data, and its stereochemistry was fully established as (1S,3R,8R) to prove no racemization during the reaction process.

A view of the molecule is represented in Fig. 1. As observed in related compounds (Gassman & Gorman, 1990; Lassaba et al., 1997; Benharref et al., 2010), each molecule is built up from two fused six-and seven-membered rings. The six-membered ring has roughly half-chair conformation with the puckering parameters: Q = 0.493 (3) Å, spherical polar angle θ= 131.2 (3)° and ϕ= 147.2 (4)° (Cremer & Pople, 1975), whereas the seven-membered ring displays a twisted chair conformation with a total puckering amplitude of 1.148 (3) Å. (Boessenkool & Boyens, 1980).

The absolute configuration (1S,3R,8R) deduced from the chemical pathway is confirmed by the refinement of the Flack's parameter, -0.015 (17), (Flack, 1983; Flack & Bernardinelli, 2000) and by the refinement of the Hooft's parameter, -0.021 (11) (Spek, 2009).

The packing of the molecules within the crystal is only stabilized by van der Waals interactions.

Related literature top

For the synthesis of the title compound, see: El Jamili et al. (2002). For further synthetic details, see: Qu et al. (2009). For biological properties of cyclopropane-containing products, see: Ajay Kumar et al. (2012); Sow et al. (2007); Symon et al. (2005). For related structures, see: Benharref et al. (2010); Gassman & Gorman (1990); Lassaba et al. (1997). For conformations of rings, see: Cremer & Pople (1975); Boessenkool & Boyens (1980); For absolute structure, see: Flack (1983); Flack & Bernardinelli (2000); Spek (2009).

Experimental top

To a cooled (0°C) solution of (1S,3R,8R)-2,2-dichloro-\3,7,7-10-tetramethyltricyclo[6.4.0.01,3]dodec-9-ene (4,6 mmol) in 50 ml of a solvent mixture THF/H2O (4/1, v/v), NBS (9,16 mmol) was added in small portions, then mixture was kept under stirring at 0°C for two hours. After completion of the reaction, 15% sodium hydrogenocarbonate solution was added and the reaction mixture was taken up in ether, dried over anhydrous sodium sulfate, and concentrated. The crude product was purified by chromatography on silica gel (230–400 mesh) with hexane as eluent to give the title compound in 9% yield.

Refinement top

All H atoms attached to C atoms were fixed geometrically and treated as riding with C—H = 0.99 Å (methylene), 0.98 Å (methyl) and 1.0 Å (methine) with Uiso(H) = 1.2Ueq(CH and CH2) or Uiso(H) = 1.5Ueq(CH3).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
(1S,3R,8R)-10-Bromomethyl-2,2-dichloro-3,7,7-trimethyltricyclo[6.4.0.01,3]dodec-9-ene top
Crystal data top
C16H23BrCl2F(000) = 752
Mr = 366.15Dx = 1.478 Mg m3
Orthorhombic, P212121Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2ac 2abCell parameters from 5474 reflections
a = 9.1000 (2) Åθ = 3.1–70.8°
b = 12.5490 (4) ŵ = 6.26 mm1
c = 14.4070 (5) ÅT = 173 K
V = 1645.22 (9) Å3Box, colourless
Z = 40.45 × 0.25 × 0.10 mm
Data collection top
Agilent Xcalibur Gemini ultra
diffractometer
3127 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source3012 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.038
Detector resolution: 16.1978 pixels mm-1θmax = 70.9°, θmin = 4.7°
ω scansh = 1111
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
k = 1514
Tmin = 0.397, Tmax = 1.000l = 1717
9248 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.027 w = 1/[σ2(Fo2) + (0.0372P)2 + 0.318P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.070(Δ/σ)max < 0.001
S = 1.04Δρmax = 0.41 e Å3
3127 reflectionsΔρmin = 0.46 e Å3
176 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.0037 (2)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1307 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.015 (17)
Crystal data top
C16H23BrCl2V = 1645.22 (9) Å3
Mr = 366.15Z = 4
Orthorhombic, P212121Cu Kα radiation
a = 9.1000 (2) ŵ = 6.26 mm1
b = 12.5490 (4) ÅT = 173 K
c = 14.4070 (5) Å0.45 × 0.25 × 0.10 mm
Data collection top
Agilent Xcalibur Gemini ultra
diffractometer
3127 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
3012 reflections with I > 2σ(I)
Tmin = 0.397, Tmax = 1.000Rint = 0.038
9248 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.070Δρmax = 0.41 e Å3
S = 1.04Δρmin = 0.46 e Å3
3127 reflectionsAbsolute structure: Flack (1983), 1307 Friedel pairs
176 parametersAbsolute structure parameter: 0.015 (17)
0 restraints
Special details top

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.

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
C10.3341 (3)0.3344 (2)0.29478 (17)0.0200 (5)
C20.4125 (3)0.2394 (2)0.33667 (17)0.0245 (5)
C30.3927 (3)0.3389 (2)0.39476 (17)0.0264 (5)
C40.2786 (4)0.3369 (2)0.47129 (18)0.0356 (6)
H4A0.32740.32080.53110.043*
H4B0.20680.27950.45860.043*
C50.1975 (4)0.4434 (2)0.47910 (19)0.0372 (6)
H5A0.25720.49250.51750.045*
H5B0.10350.43140.51200.045*
C60.1646 (3)0.4980 (2)0.38583 (18)0.0312 (6)
H6A0.10740.56340.39890.037*
H6B0.25940.52080.35860.037*
C70.0814 (3)0.4344 (2)0.31168 (19)0.0295 (6)
C80.1674 (3)0.3298 (2)0.28177 (17)0.0226 (5)
H80.13120.27140.32310.027*
C90.1316 (3)0.2964 (2)0.18373 (18)0.0259 (5)
H90.03380.27420.17090.031*
C100.2264 (3)0.2957 (2)0.11464 (16)0.0249 (5)
C110.3846 (3)0.3268 (2)0.12612 (16)0.0234 (5)
H11A0.41550.37020.07210.028*
H11B0.44600.26170.12730.028*
C120.4109 (2)0.39027 (19)0.21497 (16)0.0222 (5)
H12A0.51760.39520.22760.027*
H12B0.37170.46340.20790.027*
C130.5259 (3)0.4058 (2)0.4181 (2)0.0378 (7)
H13A0.49430.47780.43550.057*
H13B0.59070.40970.36390.057*
H13C0.57890.37330.47010.057*
C140.0692 (3)0.4003 (3)0.3467 (3)0.0564 (10)
H14A0.05770.35820.40360.085*
H14B0.11810.35700.29930.085*
H14C0.12860.46360.35990.085*
C150.0576 (4)0.5105 (2)0.2286 (2)0.0399 (7)
H15A0.00020.47420.18060.060*
H15B0.15300.53170.20310.060*
H15C0.00440.57410.24960.060*
C160.1748 (3)0.2646 (2)0.01985 (19)0.0339 (6)
H16A0.19820.32250.02440.041*
H16B0.06670.25560.02080.041*
Cl10.59023 (7)0.20569 (6)0.29648 (5)0.03423 (16)
Cl20.31861 (8)0.12015 (5)0.36321 (5)0.03703 (17)
Br10.26676 (3)0.13107 (2)0.02346 (2)0.04148 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0227 (10)0.0175 (11)0.0199 (11)0.0007 (9)0.0004 (10)0.0003 (9)
C20.0243 (11)0.0226 (12)0.0266 (12)0.0009 (10)0.0006 (10)0.0019 (10)
C30.0342 (13)0.0217 (12)0.0232 (12)0.0033 (11)0.0033 (10)0.0004 (9)
C40.0548 (16)0.0300 (14)0.0219 (11)0.0021 (13)0.0046 (14)0.0007 (10)
C50.0516 (16)0.0350 (15)0.0249 (12)0.0037 (13)0.0037 (13)0.0042 (11)
C60.0341 (14)0.0269 (14)0.0327 (14)0.0029 (12)0.0033 (12)0.0063 (11)
C70.0223 (12)0.0320 (14)0.0342 (14)0.0048 (11)0.0042 (11)0.0070 (11)
C80.0197 (10)0.0210 (13)0.0272 (13)0.0046 (9)0.0033 (10)0.0029 (9)
C90.0187 (11)0.0244 (12)0.0347 (14)0.0017 (10)0.0040 (10)0.0052 (11)
C100.0284 (13)0.0217 (11)0.0247 (11)0.0060 (11)0.0064 (10)0.0023 (9)
C110.0251 (12)0.0246 (13)0.0203 (11)0.0018 (10)0.0036 (9)0.0019 (9)
C120.0178 (10)0.0208 (12)0.0280 (12)0.0003 (10)0.0006 (9)0.0014 (10)
C130.0402 (16)0.0347 (16)0.0383 (16)0.0004 (13)0.0167 (13)0.0079 (12)
C140.0283 (15)0.057 (2)0.084 (3)0.0018 (15)0.0225 (17)0.021 (2)
C150.0409 (15)0.0380 (17)0.0408 (16)0.0156 (14)0.0075 (13)0.0083 (13)
C160.0414 (14)0.0292 (14)0.0313 (13)0.0103 (12)0.0075 (13)0.0094 (12)
Cl10.0269 (3)0.0328 (4)0.0430 (4)0.0090 (3)0.0042 (3)0.0005 (3)
Cl20.0493 (4)0.0205 (3)0.0413 (3)0.0027 (3)0.0060 (3)0.0046 (3)
Br10.03964 (16)0.03661 (18)0.04820 (18)0.00297 (14)0.00203 (13)0.01953 (14)
Geometric parameters (Å, º) top
C1—C21.515 (3)C8—H81.0000
C1—C121.518 (3)C9—C101.317 (4)
C1—C81.529 (3)C9—H90.9500
C1—C31.537 (3)C10—C161.496 (3)
C2—C31.515 (3)C10—C111.501 (3)
C2—Cl21.765 (3)C11—C121.526 (3)
C2—Cl11.769 (3)C11—H11A0.9900
C3—C131.512 (4)C11—H11B0.9900
C3—C41.515 (4)C12—H12A0.9900
C4—C51.531 (4)C12—H12B0.9900
C4—H4A0.9900C13—H13A0.9800
C4—H4B0.9900C13—H13B0.9800
C5—C61.538 (4)C13—H13C0.9800
C5—H5A0.9900C14—H14A0.9800
C5—H5B0.9900C14—H14B0.9800
C6—C71.533 (4)C14—H14C0.9800
C6—H6A0.9900C15—H15A0.9800
C6—H6B0.9900C15—H15B0.9800
C7—C141.522 (4)C15—H15C0.9800
C7—C151.546 (4)C16—Br11.974 (3)
C7—C81.589 (4)C16—H16A0.9900
C8—C91.509 (3)C16—H16B0.9900
C2—C1—C12116.7 (2)C9—C8—H8106.4
C2—C1—C8119.1 (2)C1—C8—H8106.4
C12—C1—C8112.4 (2)C7—C8—H8106.4
C2—C1—C359.50 (16)C10—C9—C8124.6 (2)
C12—C1—C3122.2 (2)C10—C9—H9117.7
C8—C1—C3117.4 (2)C8—C9—H9117.7
C3—C2—C160.98 (16)C9—C10—C16119.1 (2)
C3—C2—Cl2121.47 (19)C9—C10—C11122.9 (2)
C1—C2—Cl2121.68 (18)C16—C10—C11118.0 (2)
C3—C2—Cl1119.12 (19)C10—C11—C12112.2 (2)
C1—C2—Cl1119.24 (18)C10—C11—H11A109.2
Cl2—C2—Cl1108.12 (14)C12—C11—H11A109.2
C13—C3—C4113.4 (2)C10—C11—H11B109.2
C13—C3—C2119.0 (2)C12—C11—H11B109.2
C4—C3—C2118.0 (2)H11A—C11—H11B107.9
C13—C3—C1120.5 (2)C1—C12—C11108.8 (2)
C4—C3—C1116.3 (2)C1—C12—H12A109.9
C2—C3—C159.51 (16)C11—C12—H12A109.9
C3—C4—C5111.7 (2)C1—C12—H12B109.9
C3—C4—H4A109.3C11—C12—H12B109.9
C5—C4—H4A109.3H12A—C12—H12B108.3
C3—C4—H4B109.3C3—C13—H13A109.5
C5—C4—H4B109.3C3—C13—H13B109.5
H4A—C4—H4B107.9H13A—C13—H13B109.5
C4—C5—C6114.7 (2)C3—C13—H13C109.5
C4—C5—H5A108.6H13A—C13—H13C109.5
C6—C5—H5A108.6H13B—C13—H13C109.5
C4—C5—H5B108.6C7—C14—H14A109.5
C6—C5—H5B108.6C7—C14—H14B109.5
H5A—C5—H5B107.6H14A—C14—H14B109.5
C7—C6—C5118.3 (2)C7—C14—H14C109.5
C7—C6—H6A107.7H14A—C14—H14C109.5
C5—C6—H6A107.7H14B—C14—H14C109.5
C7—C6—H6B107.7C7—C15—H15A109.5
C5—C6—H6B107.7C7—C15—H15B109.5
H6A—C6—H6B107.1H15A—C15—H15B109.5
C14—C7—C6111.1 (2)C7—C15—H15C109.5
C14—C7—C15107.7 (3)H15A—C15—H15C109.5
C6—C7—C15106.7 (2)H15B—C15—H15C109.5
C14—C7—C8107.5 (2)C10—C16—Br1112.15 (18)
C6—C7—C8112.1 (2)C10—C16—H16A109.2
C15—C7—C8111.7 (2)Br1—C16—H16A109.2
C9—C8—C1109.8 (2)C10—C16—H16B109.2
C9—C8—C7112.2 (2)Br1—C16—H16B109.2
C1—C8—C7115.1 (2)H16A—C16—H16B107.9

Experimental details

Crystal data
Chemical formulaC16H23BrCl2
Mr366.15
Crystal system, space groupOrthorhombic, P212121
Temperature (K)173
a, b, c (Å)9.1000 (2), 12.5490 (4), 14.4070 (5)
V3)1645.22 (9)
Z4
Radiation typeCu Kα
µ (mm1)6.26
Crystal size (mm)0.45 × 0.25 × 0.10
Data collection
DiffractometerAgilent Xcalibur Gemini ultra
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2012)
Tmin, Tmax0.397, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
9248, 3127, 3012
Rint0.038
(sin θ/λ)max1)0.613
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.070, 1.04
No. of reflections3127
No. of parameters176
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.46
Absolute structureFlack (1983), 1307 Friedel pairs
Absolute structure parameter0.015 (17)

Computer programs: CrysAlis PRO (Agilent, 2012), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012).

 

References

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Volume 69| Part 11| November 2013| Pages o1692-o1693
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