(1S,3R,8R,9R,10S)-2,2-Dibromo-3,7,7,10-tetra-methyl-9β,10β-ep-oxy-3,7,7,10-tetra-methyl-tricyclo-[6.4.0.0(1,3)]dodeca-ne.

The title compound, C16H24Br2O, was synthesized from β-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzocyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus atlantica). The mol-ecule contains fused six- and seven-membered rings, each linked to a three-membered ring. The six-membered ring has a half-chair conformation, while the seven-membered ring displays a chair conformation. The dihedral angle between the mean planes through the six- and seven-membered rings is 39.55 (12)°. The two three-membered rings, linked to the six- and seven-membered rings, are nearly perpendicular to the six-membered ring, making dihedral angles of 78.6 (2) and 80.5 (2)°, respectively. The absolute structure was established unambiguously from anomalous dispersion effects. In the crystal, each mol-ecule is linked to its symmetry-equivalent partner by C-H⋯O hydrogen bonds, forming zigzag chains parallel to [100].

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 ring puckering calculations, see: Cremer & Pople (1975 ▶). For a similar structure, see: Benharref et al. (2010 ▶).

Experimental

Crystal data

C16H24Br2O

M = 392.17

Orthorhombic,

a = 7.9772 (4) Å

b = 12.8562 (7) Å

c = 16.1719 (8) Å

V = 1658.53 (15) Å3

Z = 4

Mo Kα radiation

μ = 4.88 mm−1

T = 296 K

0.41 × 0.32 × 0.27 mm

Data collection

Bruker X8 APEX diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2008 ▶) T min = 0.407, T max = 0.747

15200 measured reflections

4637 independent reflections

3298 reflections with I > 2σ(I)

R int = 0.036

Refinement

R[F 2 > 2σ(F 2)] = 0.033

wR(F 2) = 0.074

S = 1.02

4637 reflections

173 parameters

H-atom parameters constrained

Δρmax = 0.41 e Å−3

Δρmin = −0.46 e Å−3

Absolute structure: Flack & Bernardinelli (2000 ▶), 1998 Friedel pairs

Flack parameter: 0.014 (10)

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: 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, 2012 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶) and publCIF (Westrip, 2010 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536813006077/fj2620sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813006077/fj2620Isup2.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536813006077/fj2620Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C16H24Br2O	F(000) = 792
Mr = 392.17	Dx = 1.571 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: p 2ac 2ab	Cell parameters from 4637 reflections
a = 7.9772 (4) Å	θ = 2.9–29.6°
b = 12.8562 (7) Å	µ = 4.88 mm−1
c = 16.1719 (8) Å	T = 296 K
V = 1658.53 (15) Å3	Block, colourless
Z = 4	0.41 × 0.32 × 0.27 mm

Bruker X8 APEX diffractometer	4637 independent reflections
Radiation source: fine-focus sealed tube	3298 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
φ and ω scans	θmax = 29.6°, θmin = 2.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008)	h = −11→11
Tmin = 0.407, Tmax = 0.747	k = −17→15
15200 measured reflections	l = −22→14

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.033	w = 1/[σ2(Fo2) + (0.0307P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.074	(Δ/σ)max = 0.001
S = 1.02	Δρmax = 0.41 e Å−3
4637 reflections	Δρmin = −0.46 e Å−3
173 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.0016 (5)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack & Bernardinelli (2000), 1998 Friedel pairs
Secondary atom site location: difference Fourier map	Flack parameter: 0.014 (10)

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 > σ(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
C1	0.4959 (3)	0.9764 (2)	0.00560 (15)	0.0325 (5)
C2	0.6592 (3)	0.9395 (2)	0.04293 (16)	0.0404 (6)
C3	0.5934 (3)	0.8863 (2)	−0.03369 (19)	0.0448 (7)
C4	0.6887 (4)	0.9048 (3)	−0.1148 (2)	0.0587 (9)
H4A	0.7562	0.8439	−0.1270	0.070*
H4B	0.7641	0.9633	−0.1076	0.070*
C5	0.5722 (4)	0.9266 (3)	−0.1883 (2)	0.0676 (11)
H5A	0.6300	0.9089	−0.2392	0.081*
H5B	0.4741	0.8824	−0.1841	0.081*
C6	0.5167 (4)	1.0390 (3)	−0.19240 (18)	0.0596 (9)
H6A	0.4619	1.0491	−0.2454	0.072*
H6B	0.6169	1.0816	−0.1927	0.072*
C7	0.3993 (3)	1.0825 (2)	−0.12543 (16)	0.0433 (7)
C8	0.4885 (3)	1.0819 (2)	−0.03933 (15)	0.0316 (5)
H8	0.6055	1.1004	−0.0506	0.038*
C9	0.4239 (3)	1.1658 (2)	0.01801 (16)	0.0374 (6)
H9	0.4807	1.2330	0.0124	0.045*
O1	0.2442 (2)	1.17299 (17)	0.03278 (13)	0.0503 (5)
C10	0.3546 (3)	1.1457 (2)	0.10036 (16)	0.0454 (7)
C11	0.3355 (3)	1.0354 (3)	0.12860 (17)	0.0540 (8)
H11A	0.2298	1.0284	0.1577	0.065*
H11B	0.4247	1.0193	0.1673	0.065*
C12	0.3405 (3)	0.9577 (2)	0.05873 (17)	0.0434 (6)
H12A	0.2405	0.9648	0.0251	0.052*
H12B	0.3430	0.8877	0.0810	0.052*
C13	0.5257 (5)	0.7765 (3)	−0.0288 (3)	0.0738 (11)
H13A	0.4902	0.7545	−0.0828	0.111*
H13B	0.4320	0.7747	0.0084	0.111*
H13C	0.6119	0.7307	−0.0090	0.111*
C14	0.3664 (5)	1.1961 (3)	−0.1496 (2)	0.0664 (9)
H14A	0.2932	1.2275	−0.1097	0.100*
H14B	0.3149	1.1984	−0.2032	0.100*
H14C	0.4707	1.2333	−0.1511	0.100*
C15	0.2311 (3)	1.0239 (3)	−0.12733 (19)	0.0626 (9)
H15A	0.2492	0.9523	−0.1129	0.094*
H15B	0.1839	1.0279	−0.1818	0.094*
H15C	0.1552	1.0548	−0.0884	0.094*
C16	0.3686 (5)	1.2270 (3)	0.1671 (2)	0.0763 (11)
H16A	0.4449	1.2034	0.2090	0.115*
H16B	0.2602	1.2387	0.1913	0.115*
H16C	0.4094	1.2907	0.1436	0.115*
Br1	0.85914 (3)	1.02421 (3)	0.041525 (19)	0.05303 (11)
Br2	0.66225 (4)	0.86201 (3)	0.14535 (2)	0.07179 (14)

	U11	U22	U33	U12	U13	U23
C1	0.0318 (11)	0.0302 (14)	0.0355 (13)	−0.0019 (12)	0.0017 (10)	−0.0015 (12)
C2	0.0370 (12)	0.0395 (15)	0.0446 (14)	0.0013 (12)	−0.0010 (13)	0.0059 (12)
C3	0.0425 (14)	0.0336 (17)	0.0584 (17)	0.0003 (11)	−0.0005 (13)	−0.0066 (14)
C4	0.0548 (17)	0.059 (2)	0.0627 (19)	0.0102 (15)	0.0065 (15)	−0.0287 (17)
C5	0.074 (2)	0.086 (3)	0.0422 (17)	−0.001 (2)	0.0017 (16)	−0.0345 (18)
C6	0.0609 (18)	0.088 (3)	0.0302 (14)	−0.002 (2)	−0.0040 (12)	−0.0032 (16)
C7	0.0497 (15)	0.0508 (19)	0.0295 (13)	−0.0009 (13)	−0.0044 (11)	−0.0007 (12)
C8	0.0321 (11)	0.0323 (14)	0.0303 (12)	−0.0011 (10)	0.0037 (11)	0.0021 (11)
C9	0.0376 (12)	0.0331 (17)	0.0415 (15)	0.0005 (11)	0.0017 (11)	−0.0021 (12)
O1	0.0408 (9)	0.0570 (14)	0.0532 (12)	0.0160 (9)	0.0026 (9)	−0.0053 (11)
C10	0.0388 (13)	0.0579 (19)	0.0397 (14)	0.0083 (15)	0.0041 (13)	−0.0110 (13)
C11	0.0461 (15)	0.075 (2)	0.0411 (15)	0.0023 (17)	0.0126 (13)	0.0073 (15)
C12	0.0327 (12)	0.0433 (17)	0.0543 (16)	−0.0012 (13)	0.0049 (12)	0.0120 (13)
C13	0.066 (2)	0.033 (2)	0.123 (4)	−0.0004 (16)	−0.013 (2)	−0.007 (2)
C14	0.079 (2)	0.071 (2)	0.0487 (17)	0.011 (2)	−0.0039 (19)	0.0207 (17)
C15	0.0542 (16)	0.090 (3)	0.0436 (16)	−0.0074 (19)	−0.0102 (13)	−0.0064 (19)
C16	0.076 (2)	0.089 (3)	0.064 (2)	0.012 (2)	0.0117 (19)	−0.039 (2)
Br1	0.03457 (13)	0.0605 (2)	0.06396 (19)	−0.00414 (15)	−0.00528 (13)	−0.00561 (16)
Br2	0.0688 (2)	0.0793 (3)	0.0673 (2)	0.0137 (2)	−0.00527 (18)	0.03512 (19)

C1—C2	1.512 (3)	C9—O1	1.457 (3)
C1—C12	1.527 (3)	C9—C10	1.465 (4)
C1—C3	1.533 (4)	C9—H9	0.9800
C1—C8	1.540 (4)	O1—C10	1.447 (3)
C2—C3	1.510 (4)	C10—C11	1.498 (4)
C2—Br1	1.931 (3)	C10—C16	1.507 (4)
C2—Br2	1.933 (3)	C11—C12	1.508 (4)
C3—C13	1.513 (5)	C11—H11A	0.9700
C3—C4	1.534 (4)	C11—H11B	0.9700
C4—C5	1.535 (5)	C12—H12A	0.9700
C4—H4A	0.9700	C12—H12B	0.9700
C4—H4B	0.9700	C13—H13A	0.9600
C5—C6	1.512 (6)	C13—H13B	0.9600
C5—H5A	0.9700	C13—H13C	0.9600
C5—H5B	0.9700	C14—H14A	0.9600
C6—C7	1.537 (4)	C14—H14B	0.9600
C6—H6A	0.9700	C14—H14C	0.9600
C6—H6B	0.9700	C15—H15A	0.9600
C7—C14	1.534 (5)	C15—H15B	0.9600
C7—C15	1.540 (4)	C15—H15C	0.9600
C7—C8	1.564 (3)	C16—H16A	0.9600
C8—C9	1.513 (4)	C16—H16B	0.9600
C8—H8	0.9800	C16—H16C	0.9600
C2—C1—C12	115.2 (2)	O1—C9—C8	118.8 (2)
C2—C1—C3	59.43 (18)	C10—C9—C8	124.1 (2)
C12—C1—C3	121.8 (2)	O1—C9—H9	114.5
C2—C1—C8	119.8 (2)	C10—C9—H9	114.5
C12—C1—C8	111.9 (2)	C8—C9—H9	114.5
C3—C1—C8	119.3 (2)	C10—O1—C9	60.61 (16)
C3—C2—C1	60.96 (18)	O1—C10—C9	60.03 (16)
C3—C2—Br1	122.22 (19)	O1—C10—C11	113.5 (2)
C1—C2—Br1	122.02 (19)	C9—C10—C11	118.8 (2)
C3—C2—Br2	118.3 (2)	O1—C10—C16	114.7 (3)
C1—C2—Br2	120.94 (17)	C9—C10—C16	120.1 (3)
Br1—C2—Br2	106.89 (12)	C11—C10—C16	116.5 (3)
C2—C3—C13	120.3 (3)	C10—C11—C12	113.3 (2)
C2—C3—C1	59.61 (18)	C10—C11—H11A	108.9
C13—C3—C1	120.1 (3)	C12—C11—H11A	108.9
C2—C3—C4	117.3 (2)	C10—C11—H11B	108.9
C13—C3—C4	111.4 (3)	C12—C11—H11B	108.9
C1—C3—C4	119.3 (3)	H11A—C11—H11B	107.7
C3—C4—C5	113.0 (3)	C11—C12—C1	109.8 (2)
C3—C4—H4A	109.0	C11—C12—H12A	109.7
C5—C4—H4A	109.0	C1—C12—H12A	109.7
C3—C4—H4B	109.0	C11—C12—H12B	109.7
C5—C4—H4B	109.0	C1—C12—H12B	109.7
H4A—C4—H4B	107.8	H12A—C12—H12B	108.2
C6—C5—C4	112.7 (3)	C3—C13—H13A	109.5
C6—C5—H5A	109.0	C3—C13—H13B	109.5
C4—C5—H5A	109.0	H13A—C13—H13B	109.5
C6—C5—H5B	109.0	C3—C13—H13C	109.5
C4—C5—H5B	109.0	H13A—C13—H13C	109.5
H5A—C5—H5B	107.8	H13B—C13—H13C	109.5
C5—C6—C7	119.7 (3)	C7—C14—H14A	109.5
C5—C6—H6A	107.4	C7—C14—H14B	109.5
C7—C6—H6A	107.4	H14A—C14—H14B	109.5
C5—C6—H6B	107.4	C7—C14—H14C	109.5
C7—C6—H6B	107.4	H14A—C14—H14C	109.5
H6A—C6—H6B	106.9	H14B—C14—H14C	109.5
C14—C7—C6	105.7 (3)	C7—C15—H15A	109.5
C14—C7—C15	108.2 (3)	C7—C15—H15B	109.5
C6—C7—C15	109.8 (3)	H15A—C15—H15B	109.5
C14—C7—C8	108.1 (2)	C7—C15—H15C	109.5
C6—C7—C8	110.4 (2)	H15A—C15—H15C	109.5
C15—C7—C8	114.3 (2)	H15B—C15—H15C	109.5
C9—C8—C1	110.6 (2)	C10—C16—H16A	109.5
C9—C8—C7	112.7 (2)	C10—C16—H16B	109.5
C1—C8—C7	116.3 (2)	H16A—C16—H16B	109.5
C9—C8—H8	105.4	C10—C16—H16C	109.5
C1—C8—H8	105.4	H16A—C16—H16C	109.5
C7—C8—H8	105.4	H16B—C16—H16C	109.5
O1—C9—C10	59.36 (18)

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9···O1i	0.98	2.53	3.391 (3)	146

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9⋯O1i	0.98	2.53	3.391 (3)	146

Symmetry code: (i) .