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 70| Part 1| January 2014| Pages o81-o82

(1R,3S,8R)-3,7,7,10-Tetra­methyl­tri­cyclo­[6.4.0.01,3]dodec-9-en-11-one

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: a.auhmani@uca.ma

(Received 4 October 2013; accepted 17 December 2013; online 21 December 2013)

The absolute configuration of the title compound, C16H24O, has been deduced from the chemical pathway. The six-membered ring has a roughly half-chair conformation with the quaternary C atom as the flap. The seven-membered ring displays a chair conformation. In the crystal, there is a weak C—H⋯O hydrogen bond between the methyl­ene group of the cyclo­propane ring and the carbonyl group of a screw-axis-related mol­ecule, which builds up a zigzag-like chain along the b-axis direction.

Related literature

For related structures, see: Benharref et al. (2012[Benharref, A., El Ammari, L., Lassaba, E., Ourhriss, N. & Berraho, M. (2012). Acta Cryst. E68, o2502.]); Gassman & Gorman (1990[Gassman, P. G. & Gorman, D. B. (1990). J. Am. Chem. Soc. 112, 8623.]); Lassaba et al. (1997[Lassaba, E., Benharref, A., Giorgi, M. & Pierrot, M. (1997). Acta Cryst. C53, 1943-1945.]). For ring puckering analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For structural discussion, see: Evans & Boeyens (1989[Evans, D. G. & Boeyens, J. C. A. (1989). Acta Cryst. B45, 581-590.]); Spek (2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]). For chemical properties, see: Auhmani et al. (2002[Auhmani, A., Kossareva, E., Eljamili, H., Reglier, M., Pierrot, M. & Benharref, A. (2002). Synth. Commun. 32, 707-715.]); Danyang et al. (2007[Danyang, L., Bastiaan, J. V., Hakan, V. W. & Durk, D. (2007). Tetrahedron, 63, 7264-7270.]); Tetsuhiro et al. (2003[Tetsuhiro, N., Takashi, O. & Masakatsu, S. (2003). Tetrahedron, 59, 6889-6897.]).

[Scheme 1]

Experimental

Crystal data
  • C16H24O

  • Mr = 232.35

  • Monoclinic, P 21

  • a = 6.4379 (2) Å

  • b = 7.8889 (3) Å

  • c = 13.5122 (5) Å

  • β = 97.430 (2)°

  • V = 680.49 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 180 K

  • 0.38 × 0.23 × 0.08 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008a[Sheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany.]) Tmin = 0.661, Tmax = 0.747

  • 15568 measured reflections

  • 4902 independent reflections

  • 4331 reflections with I > 2σ(I)

  • Rint = 0.030

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.111

  • S = 1.04

  • 4902 reflections

  • 158 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2B⋯O1i 0.99 2.60 3.541 (2) 160
Symmetry code: (i) [-x+1, y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXL2013 (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]), ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL2013.

Supporting information


Comment top

α,β-unsaturated ketones are versatile intermediates in organic synthesis, since they are important precursors in the synthesis of enaminones (Auhmani et al., 2002), prodrugs (Danyang et al., 2007) and natural compounds (Tetsuhiro et al., 2003).

With the aim of preparing a new α,β-unsaturated ketone with sesquiterpenic skeleton, we report here the synthesis of (1R,3S,8R)-3,7,7,10-tetramethyltricyclo[6.4.0.01.3]dodec-9-en-11-one, 1. (1S,3S,8R)-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-ene, 2, was treated with N-bromosuccinimide (NBS). The reaction was conducted at 0°C to provide the α,β-unsaturated ketone 1 as colorless crystals in 62% yield. Its structure was characterized by its mass and NMR spectroscopic data. Furthermore, an X-ray single-crystal structure analysis allowed its complete identification as (1R,3S,8R)-3,7,7,10-tetramethyltricyclo[6.4.0.01.3]dodec-9-en-11-one.

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., 2012), 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 = 0.4166 (11) Å, spherical polar angle θ = 124.02 (15)° and ϕ = 170.57 (19)° (Spek, 2009; Cremer & Pople, 1975), whereas the seven-membered ring displays a chair conformation with a total puckering amplitude of 0.7919 (11) Å (Evans & Boeyens, 1989).

There is a weak C—H···O hydrogen bond, which builds up a zigzag-like chain developing along the b axis (Table 1, Fig. 2)

Related literature top

For related structures, see: Benharref et al. (2012); Gassman & Gorman (1990); Lassaba et al. (1997). For structural discussion, see: Cremer & Pople (1975); Evans & Boeyens (1989); Spek (2009). For chemical properties, see: Auhmani et al. (2002); Danyang et al. (2007); Tetsuhiro et al. (2003).

Experimental top

To a cooled (0°C) solution of (1S,3S,8R)-3,7,7,10-tetramethyl tricyclo[6.4.0.01,3]dodec-9-ene 2 (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. The 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 evaporated. The crude product was purified by silica gel chromatography (230–400 mesh) using hexane/ethyl acetate (95:5) as eluent to give (1R,3S,8R)-3,7,7,10-tetramethyltricyclo[6.4.0.01.3]dodec-9-en-11-one, 1 (2.85 mmol) in 62% yield. X-ray quality crystals were obtained by slow solvent evaporation from an isohexane solution of the title compound.

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), 0.95 Å (methine) with Uiso(H) = 1.2Ueq(CH and CH2) or Uiso(H) = 1.5Ueq(CH3).

In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and any references to the Flack parameter were removed.

The 0 0 1 reflection appears affected by the beam stop and it has been removed.

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008b); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008b).

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.
[Figure 2] Fig. 2. Partial packing view (Mercury) showing the weak C—H···O interaction as dashed lines.
(1R,3S,8R)-3,7,7,10-Tetramethyltricyclo[6.4.0.01,3]dodec-9-en-11-one top
Crystal data top
C16H24OF(000) = 256
Mr = 232.35Dx = 1.134 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 7217 reflections
a = 6.4379 (2) Åθ = 3.0–33.0°
b = 7.8889 (3) ŵ = 0.07 mm1
c = 13.5122 (5) ÅT = 180 K
β = 97.430 (2)°Plate, colourless
V = 680.49 (4) Å30.38 × 0.23 × 0.08 mm
Z = 2
Data collection top
Bruker APEXII CCD
diffractometer
4902 independent reflections
Radiation source: sealed tube4331 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.030
ϕ and ω scansθmax = 33.2°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
h = 99
Tmin = 0.661, Tmax = 0.747k = 1212
15568 measured reflectionsl = 2020
Refinement top
Refinement on F21 restraint
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.041H-atom parameters constrained
wR(F2) = 0.111 w = 1/[σ2(Fo2) + (0.0667P)2 + 0.0218P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
4902 reflectionsΔρmax = 0.30 e Å3
158 parametersΔρmin = 0.18 e Å3
Crystal data top
C16H24OV = 680.49 (4) Å3
Mr = 232.35Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.4379 (2) ŵ = 0.07 mm1
b = 7.8889 (3) ÅT = 180 K
c = 13.5122 (5) Å0.38 × 0.23 × 0.08 mm
β = 97.430 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
4902 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
4331 reflections with I > 2σ(I)
Tmin = 0.661, Tmax = 0.747Rint = 0.030
15568 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0411 restraint
wR(F2) = 0.111H-atom parameters constrained
S = 1.04Δρmax = 0.30 e Å3
4902 reflectionsΔρmin = 0.18 e Å3
158 parameters
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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.31651 (18)0.79421 (18)0.28074 (9)0.0192 (2)
C20.2552 (2)0.98024 (19)0.27484 (11)0.0255 (3)
H2A0.11041.00880.24570.031*
H2B0.31591.05550.32970.031*
C30.40116 (18)0.91018 (18)0.20572 (9)0.0213 (3)
C40.3155 (2)0.8894 (2)0.09629 (10)0.0261 (3)
H4A0.37060.98210.05770.031*
H4B0.16110.90050.08880.031*
C50.3716 (2)0.7200 (2)0.05222 (11)0.0318 (3)
H5A0.51480.68760.08190.038*
H5B0.37270.73380.02050.038*
C60.2204 (3)0.5769 (2)0.07006 (11)0.0322 (3)
H6A0.25650.47780.03080.039*
H6B0.07800.61350.04170.039*
C70.2086 (2)0.51533 (19)0.17792 (10)0.0244 (3)
C80.14660 (17)0.66525 (17)0.24508 (9)0.0191 (2)
H80.03590.73040.20230.023*
C90.04465 (19)0.60496 (19)0.33343 (10)0.0236 (3)
H90.08700.54990.31910.028*
C100.1211 (2)0.6213 (2)0.42964 (11)0.0263 (3)
C110.3324 (2)0.6937 (2)0.45837 (10)0.0271 (3)
C120.4560 (2)0.7448 (2)0.37599 (10)0.0263 (3)
H12A0.54710.64930.36140.032*
H12B0.54740.84180.39880.032*
C130.6305 (2)0.9621 (2)0.22205 (12)0.0310 (3)
H13A0.66970.99410.29210.047*
H13B0.65211.05890.17910.047*
H13C0.71750.86690.20560.047*
C140.4145 (2)0.4307 (2)0.22037 (13)0.0352 (4)
H14A0.43830.33080.18020.053*
H14B0.40720.39600.28950.053*
H14C0.53010.51100.21860.053*
C150.0350 (3)0.3801 (2)0.16921 (14)0.0372 (4)
H15A0.03270.32510.23410.056*
H15B0.06260.29500.11970.056*
H15C0.10070.43390.14830.056*
C160.0016 (3)0.5678 (3)0.51319 (14)0.0403 (4)
H16A0.13220.51730.48520.060*
H16B0.02460.66700.55340.060*
H16C0.08390.48430.55530.060*
O10.4059 (2)0.7093 (2)0.54568 (8)0.0492 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0190 (4)0.0222 (6)0.0168 (5)0.0001 (4)0.0033 (4)0.0009 (4)
C20.0287 (6)0.0230 (7)0.0263 (6)0.0003 (5)0.0095 (5)0.0021 (5)
C30.0214 (5)0.0230 (7)0.0202 (6)0.0001 (4)0.0055 (4)0.0023 (5)
C40.0300 (6)0.0289 (7)0.0199 (6)0.0033 (5)0.0047 (4)0.0061 (5)
C50.0407 (7)0.0376 (9)0.0189 (6)0.0035 (6)0.0100 (5)0.0003 (6)
C60.0446 (7)0.0312 (8)0.0208 (7)0.0009 (6)0.0043 (5)0.0060 (6)
C70.0277 (5)0.0225 (7)0.0227 (6)0.0030 (5)0.0019 (4)0.0019 (5)
C80.0175 (4)0.0214 (6)0.0181 (5)0.0022 (4)0.0015 (4)0.0013 (5)
C90.0205 (5)0.0246 (7)0.0263 (6)0.0004 (5)0.0057 (4)0.0040 (5)
C100.0284 (6)0.0277 (7)0.0242 (6)0.0020 (5)0.0082 (5)0.0070 (5)
C110.0308 (6)0.0311 (8)0.0190 (6)0.0015 (5)0.0019 (4)0.0064 (5)
C120.0225 (5)0.0371 (8)0.0185 (6)0.0035 (5)0.0000 (4)0.0033 (5)
C130.0240 (5)0.0370 (9)0.0326 (7)0.0047 (5)0.0061 (5)0.0056 (6)
C140.0369 (7)0.0299 (8)0.0390 (8)0.0146 (6)0.0056 (6)0.0002 (6)
C150.0438 (8)0.0276 (8)0.0393 (8)0.0068 (6)0.0020 (6)0.0064 (7)
C160.0423 (7)0.0500 (11)0.0312 (8)0.0022 (7)0.0150 (6)0.0136 (7)
O10.0509 (6)0.0765 (11)0.0185 (5)0.0110 (7)0.0021 (4)0.0070 (6)
Geometric parameters (Å, º) top
C1—C31.5181 (18)C8—H81.0000
C1—C21.519 (2)C9—C101.336 (2)
C1—C121.5220 (18)C9—H90.9500
C1—C81.5255 (18)C10—C111.4796 (19)
C2—C31.5123 (17)C10—C161.5065 (19)
C2—H2A0.9900C11—O11.2192 (17)
C2—H2B0.9900C11—C121.5048 (18)
C3—C41.5186 (19)C12—H12A0.9900
C3—C131.5207 (17)C12—H12B0.9900
C4—C51.525 (2)C13—H13A0.9800
C4—H4A0.9900C13—H13B0.9800
C4—H4B0.9900C13—H13C0.9800
C5—C61.530 (2)C14—H14A0.9800
C5—H5A0.9900C14—H14B0.9800
C5—H5B0.9900C14—H14C0.9800
C6—C71.548 (2)C15—H15A0.9800
C6—H6A0.9900C15—H15B0.9800
C6—H6B0.9900C15—H15C0.9800
C7—C141.528 (2)C16—H16A0.9800
C7—C151.538 (2)C16—H16B0.9800
C7—C81.5733 (18)C16—H16C0.9800
C8—C91.5115 (17)
C3—C1—C259.73 (9)C1—C8—C7117.29 (9)
C3—C1—C12119.71 (10)C9—C8—H8105.6
C2—C1—C12114.38 (12)C1—C8—H8105.6
C3—C1—C8119.72 (11)C7—C8—H8105.6
C2—C1—C8117.19 (10)C10—C9—C8126.53 (12)
C12—C1—C8114.63 (11)C10—C9—H9116.7
C3—C2—C160.10 (9)C8—C9—H9116.7
C3—C2—H2A117.8C9—C10—C11120.23 (11)
C1—C2—H2A117.8C9—C10—C16122.86 (13)
C3—C2—H2B117.8C11—C10—C16116.91 (14)
C1—C2—H2B117.8O1—C11—C10121.43 (13)
H2A—C2—H2B114.9O1—C11—C12120.82 (13)
C2—C3—C160.17 (9)C10—C11—C12117.73 (12)
C2—C3—C4117.69 (11)C11—C12—C1112.55 (10)
C1—C3—C4117.95 (11)C11—C12—H12A109.1
C2—C3—C13118.74 (12)C1—C12—H12A109.1
C1—C3—C13119.42 (11)C11—C12—H12B109.1
C4—C3—C13113.19 (11)C1—C12—H12B109.1
C3—C4—C5113.60 (12)H12A—C12—H12B107.8
C3—C4—H4A108.8C3—C13—H13A109.5
C5—C4—H4A108.8C3—C13—H13B109.5
C3—C4—H4B108.8H13A—C13—H13B109.5
C5—C4—H4B108.8C3—C13—H13C109.5
H4A—C4—H4B107.7H13A—C13—H13C109.5
C4—C5—C6113.40 (11)H13B—C13—H13C109.5
C4—C5—H5A108.9C7—C14—H14A109.5
C6—C5—H5A108.9C7—C14—H14B109.5
C4—C5—H5B108.9H14A—C14—H14B109.5
C6—C5—H5B108.9C7—C14—H14C109.5
H5A—C5—H5B107.7H14A—C14—H14C109.5
C5—C6—C7119.33 (13)H14B—C14—H14C109.5
C5—C6—H6A107.5C7—C15—H15A109.5
C7—C6—H6A107.5C7—C15—H15B109.5
C5—C6—H6B107.5H15A—C15—H15B109.5
C7—C6—H6B107.5C7—C15—H15C109.5
H6A—C6—H6B107.0H15A—C15—H15C109.5
C14—C7—C15108.17 (13)H15B—C15—H15C109.5
C14—C7—C6110.16 (12)C10—C16—H16A109.5
C15—C7—C6105.63 (12)C10—C16—H16B109.5
C14—C7—C8112.60 (11)H16A—C16—H16B109.5
C15—C7—C8109.25 (11)C10—C16—H16C109.5
C6—C7—C8110.74 (12)H16A—C16—H16C109.5
C9—C8—C1109.11 (10)H16B—C16—H16C109.5
C9—C8—C7112.79 (12)
C12—C1—C2—C3111.44 (11)C3—C1—C8—C767.20 (16)
C8—C1—C2—C3110.21 (12)C2—C1—C8—C7136.14 (12)
C1—C2—C3—C4108.01 (14)C12—C1—C8—C785.61 (13)
C1—C2—C3—C13109.34 (14)C14—C7—C8—C980.64 (14)
C12—C1—C3—C2102.54 (14)C15—C7—C8—C939.58 (15)
C8—C1—C3—C2106.03 (12)C6—C7—C8—C9155.52 (11)
C2—C1—C3—C4107.58 (13)C14—C7—C8—C147.41 (16)
C12—C1—C3—C4149.87 (13)C15—C7—C8—C1167.63 (12)
C8—C1—C3—C41.55 (17)C6—C7—C8—C176.43 (14)
C2—C1—C3—C13108.24 (15)C1—C8—C9—C1017.09 (19)
C12—C1—C3—C135.7 (2)C7—C8—C9—C10115.13 (15)
C8—C1—C3—C13145.73 (13)C8—C9—C10—C114.7 (2)
C2—C3—C4—C5134.89 (13)C8—C9—C10—C16175.72 (16)
C1—C3—C4—C565.84 (15)C9—C10—C11—O1179.74 (16)
C13—C3—C4—C580.48 (16)C16—C10—C11—O10.1 (2)
C3—C4—C5—C684.92 (16)C9—C10—C11—C120.8 (2)
C4—C5—C6—C765.63 (18)C16—C10—C11—C12178.82 (15)
C5—C6—C7—C1466.50 (18)O1—C11—C12—C1153.30 (16)
C5—C6—C7—C15176.90 (14)C10—C11—C12—C127.8 (2)
C5—C6—C7—C858.73 (16)C3—C1—C12—C11156.43 (13)
C3—C1—C8—C9163.00 (11)C2—C1—C12—C1188.68 (15)
C2—C1—C8—C994.06 (13)C8—C1—C12—C1150.76 (17)
C12—C1—C8—C944.19 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2B···O1i0.992.603.541 (2)160
Symmetry code: (i) x+1, y+1/2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2B···O1i0.992.603.541 (2)159.8
Symmetry code: (i) x+1, y+1/2, z+1.
 

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Volume 70| Part 1| January 2014| Pages o81-o82
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