Corymbolone

Stacey Burrett; Dennis K Taylor; Edward R T Tiekink

doi:10.1107/S1600536814012938

. 2014 Jun 11;70(Pt 7):o758. doi: 10.1107/S1600536814012938

Corymbolone

Stacey Burrett ^a, Dennis K Taylor ^a,^*, Edward R T Tiekink ^b,^*

PMCID: PMC4120577 PMID: 25161551

Abstract

The title compound, C₁₅H₂₄O₂ [systematic name: (4S,4aR,6R,8aR)-4a-hydroxy-4,8a-dimethyl-6-(prop-1-en-2-yl)octahydronaphthalen-1(2H)-one], features two edge-shared six-membered rings with the hydroxyl and methyl substituents at this bridge being trans. One adopts a flattened chair conformation with the C atoms bearing the carbonyl and methyl substituents lying 0.5227 (16) and 0.6621 (15) Å, respectively, above and below the mean plane through the remaining four C atoms (r.m.s. deviation = 0.0145 Å). The second ring, bearing the prop-1-en-2-yl group, has a chair conformation. Supramolecular helical chains along the b axis are found in the crystal packing, which are sustained by hydroxy–carbonyl O—H⋯O hydrogen bonding.

Related literature

For the first isolation and the spectroscopic data of corymbolone, see: Garbarino et al. (1985 ▶). For the synthesis of corymbolone in racemic form, see: Ferraz et al. (2006 ▶). graphic file with name e-70-0o758-scheme1.jpg

Experimental

Crystal data

C₁₅H₂₄O₂
M _r = 236.34
Monoclinic,
a = 6.1057 (2) Å
b = 12.1389 (2) Å
c = 9.2737 (2) Å
β = 99.302 (2)°
V = 678.30 (3) Å³
Z = 2
Cu Kα radiation
μ = 0.58 mm⁻¹
T = 100 K
0.30 × 0.25 × 0.20 mm

Data collection

Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013 ▶) T _min = 0.689, T _max = 1.000
4848 measured reflections
2631 independent reflections
2621 reflections with I > 2σ(I)
R _int = 0.011

Refinement

R[F ² > 2σ(F ²)] = 0.030
wR(F ²) = 0.083
S = 1.03
2631 reflections
161 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.24 e Å⁻³
Δρ_min = −0.14 e Å⁻³
Absolute structure: Flack (1983 ▶), 1200 Friedel pairs
Absolute structure parameter: 0.02 (16)

Data collection: CrysAlis PRO (Agilent, 2013 ▶); cell refinement: 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 ▶) and DIAMOND (Brandenburg, 2006 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablock(s) general, I. DOI: 10.1107/S1600536814012938/su2741sup1.cif

e-70-0o758-sup1.cif^{(19.9KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814012938/su2741Isup2.hkl

e-70-0o758-Isup2.hkl^{(129.2KB, hkl)}

Click here for additional data file.^{(5.9KB, cml)}

Supporting information file. DOI: 10.1107/S1600536814012938/su2741Isup3.cml

CCDC reference: 1006604

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O1ⁱ	0.863 (19)	1.993 (19)	2.8513 (12)	172.5 (16)

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Symmetry code: (i) Inline graphic .

Acknowledgments

This project was supported in part by the School of Agriculture, Food and Wine, The University of Adelaide, and by Australia’s grape growers and wine makers through their investment body, the Grape and Wine Research and Development Corporation, with matching funds from the Australian Government. SB thanks the Faculty of Science for a PhD scholarship. Intensity data were provided by the University of Malaya Crystallographic Laboratory. We thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR-MOHE/SC/03).

supplementary crystallographic information

S1. Structural commentary

The title compound, corymbolone, was first characterised in 1985 (Garbarino et al., 1985), and more recently synthesized in racemic form (Ferraz et al., 2006). In the present study, it was isolated from the product mixture that resulted from aerial oxidation of α-guaiene.

The molecular structure of the title molecule, Fig. 1, features two fused six-membered rings. The C2,C3,C5 and C6 atoms of the C1–C6 ring are planar with a r.m.s. deviation of 0.0145 Å, and with the C1 and C4 atoms lying 0.5227 (16) and 0.6621 (15) Å above and below this plane, respectively, so that the conformation of the ring is best described as being a flattened chair. By contrast, the C5–C10 ring closely approximates a chair conformation. With respect to the C1–C6 ring the C1-carbonyl, C4-methyl, C5-hydroxyl and C6-methyl groups have equatorial (eq), axial (ax), ax and eq dispositions, respectively. For the C5–C10 ring, the C5-hydroxyl, C6-methyl and C9-prop-1-en-2-yl groups have have ax, ax and eq dispositions, respectively.

The most prominent feature of the crystal packing is the formation of hydroxyl-O—H···O(carbonyl) hydrogen bonding that leads to helical supramolecular chains along the b axis (Table 1 and Fig. 2).

S2. Synthesis and crystallization

Air was slowly bubbled through a neat solution of α-guaiene (7.0 g, 34.3 mmol) and after 21 days the crude mixture of products was subjected to column chromatography with a gradient of 100% hexane to 100% EtOAc. The product (0.12 g, 1.5%) at Rf 0.07 (10% EtOAc/hexane) was collected as a white crystalline solid and recrystallized from hexane to afford block-like colourless crystals of corymboline. M.p. 408–409 K; Lit. M.p. 409–410 K (Garbarino et al., 1985). Spectroscopic data for the title compound are available in the archived CIF.

S3. Refinement

The hydroxy-H atom was located in a difference Fourier map and freely refined. C-bound H-atoms were placed in calculated positions [C—H = 0.95 - 1.00 Å] and included in the refinement in the riding model approximation with U_iso(H) = 1.5U_eq(C-methyl) and = 1.2U_eq(C) for other H atoms. Owing to poor agreement, two reflections, i.e. (1 1 0) and (2 -4 2), were omitted from the final cycles of refinement.