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

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ISSN: 2056-9890

1-(4a,8-Di­methyl-1,2,3,4,4a,5,6,8a-octa­hydro­naphthalen-2-yl)-3-phenyl­prop-2-en-1-one

aLaboratoire de Chimie Bioorganique et Analytique, URAC 22. BP 146, FSTM, Université Hassan II, Mohammedia-Casablanca 20810 Mohammedia, Morocco, bLaboratoire de Chimie Biomoleculaire, Substances Naturelles et Réactivite, URAC16, Université Cadi Ayyad, Faculté des Sciences Semlalia, BP 2390, Bd My Abdellah, 40000 Marrakech, Morocco, and cLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: makssira@yahoo.com

(Received 17 March 2011; accepted 20 March 2011; online 26 March 2011)

The title compound, C21H26O, was semisynthesized from isocostic acid, isolated from the aerial part of Inula Viscosa­ (L) Aiton [or Dittrichia Viscosa­ (L) Greuter]. The cyclo­hexene ring has a half-chair conformation, whereas the cyclo­hexane ring displays a chair conformation.

Related literature

For background to the medicinal inter­est in Inula Viscosa­ (L) Aiton [or Dittrichia Viscosa­ (L) Greuter], see: Shtacher & Kasshman (1970[Shtacher, G. & Kasshman, Y. (1970). J. Med. Chem. 13, 1221-1223.]); Bohlman & Gupta (1982[Bohlman, F. & Gupta, R. K. (1982). Phytochemistry, 21, 1443-1445.]); Azoulay et al. (1986[Azoulay, P., Reynier, J. P., Balansard, G., Gasquet, M. & Timon-David, P. (1986). Pharm. Acta Helv. 61, 345-352.]); Bohlmann et al. (1977[Bohlmann, F., Czerson, H. & Schoneweib, S. (1977). Chem. Ber. 110, 1330-1334.]); Ceccherelli et al. (1988[Ceccherelli, P., Curini, M. & Marcotullio, M. C. (1988). J. Nat. Prod. 51, 1006-1009.]). For the synthesis, see: Kutney & Singh (1984[Kutney, J. P. & Singh, A. (1984). Can. J. Chem. 62, 1407-1409.]). For conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C21H26O

  • Mr = 294.42

  • Orthorhombic, P 21 21 21

  • a = 9.5760 (8) Å

  • b = 11.3542 (11) Å

  • c = 15.7852 (13) Å

  • V = 1716.3 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 180 K

  • 0.37 × 0.16 × 0.16 mm

Data collection
  • Agilent Xcalibur Eos Gemini ultra diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010[Agilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.817, Tmax = 1.000

  • 10251 measured reflections

  • 3436 independent reflections

  • 3180 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.089

  • S = 1.05

  • 3436 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.15 e Å−3

Data collection: CrysAlis PRO (Agilent, 2010[Agilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Our work lies within the framework of the valorization of medicinals plants and concerning Inula Viscosa(L) Aiton or Dittrichia Viscosa (L) Greuter. This plant is widespread in Mediterranean area and extends to the Atlantic cost of Morocco. It is a well known medicinal plant (Shtacher & Kasshman, 1970; Bohlman & Gupta, 1982) and has some pharmacological activities (Azoulay et al., 1986). This plant has been the subject of chemical investigation in terms of isolating sesquiterpene lactones (Bohlmann et al., 1977), sesquiterpene acids (Ceccherelli et al., 1988). The isocostic acid is a major constituent of the dichloromethane extract of the Inula viscosa (L).The literature does not report any article on the transformation of this acid. In order to prepare products with high added value, we studied the reactivity of this acid. Thus, from this acid, we have prepared by reaction of Curtius the 1 - (4a, 8dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen-2-yl)- ethanone which was synthesized (Kutney et al.,1984). The Condensation of this ketone with benzaldehyde in the presence of sodium hydroxide allows us to obtain the title compound with a good yield of 85%. The structure of this new derivative of isocostic acid was established by NMR spectral analysis of 1H, 13 C and mass spectroscopy and confirmed by its single-crystal X-ray structure. The molecule is built up from two fused six-membered rings, substituted by 3-phenylpropenoyl. The molecular structure of (I), Fig.1, shows the cyclohexane ring to adopt a chair conformation, as indicated by the total puckering amplitude QT = 0.5674 (19)Å and spherical polar angle θ =4.83 (19)° with ϕ = 266 (2)°. While the cyclohexene ring has a half chair conformation with QT = 0.5005 (19) Å, θ =47.9 (2)°, ϕ = 13.7 (3)° (Cremer & Pople, 1975).

Related literature top

For background to the medicinal interest in Inula Viscosa (L) Aiton [or Dittrichia Viscosa (L) Greuter], see: Shtacher & Kasshman (1970); Bohlman & Gupta (1982); Azoulay et al. (1986); Bohlmann et al. (1977); Ceccherelli et al. (1988). For the synthesis, see: Kutney & Singh (1984). For conformational analysis, see: Cremer & Pople (1975).

Experimental top

In a flask was introduced a mixture of 500 mg (2.42 mmol), of 1 - (4a, 8-dimethyl-1, 2,3,4,4a,5,6,8a-octahydronaphthalen- 2-yl)-ethanone, 257 mg (2.42 mmol.) of benzaldehyde, 30 ml of anhydrous ethanol and 1 ml of a solution of sodium hydroxide(2 N). The mixture was stirred for three hours at room temperature. After neutralization followed by extraction three time with 20 ml of dichloromethane, the organic phase is dried over sodium sulfate, then evaporated under vacuum. Chromatography on a column of silica gel with hexane-ethyl acetate (97/3) as eluent of the residue allowed us to obtain 1-(4a, 8-dimethyl-1,2,3,4,4a, 5,6,8a-octahydronaphthalen-2-yl)-3-phenylprop-2-en-1-one with a yield of 85%. The title compound is recrystallized in hexane- ethyl acetate (80/20).

Refinement top

All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.97 Å (methylene), 0.98Å (methine) with Uiso(H) = 1.2Ueq (methylene, methine) or Uiso(H) = 1.5Ueq (methyl). In the absence of significant anomalous scattering, the absolute configuration could not be reliably determined and thus 1436 Friedel pairs were merged and any references to the Flack parameter were removed.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SHELXL97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. : Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability. level. H atoms are represented as small spheres of arbitrary radii.
1-(4a,8-Dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen-2-yl)- 3-phenylprop-2-en-1-one top
Crystal data top
C21H26OF(000) = 640
Mr = 294.42Dx = 1.139 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6842 reflections
a = 9.5760 (8) Åθ = 3.3–27.2°
b = 11.3542 (11) ŵ = 0.07 mm1
c = 15.7852 (13) ÅT = 180 K
V = 1716.3 (3) Å3Box, colorless
Z = 40.37 × 0.16 × 0.16 mm
Data collection top
Agilent Xcalibur Eos Gemini ultra
diffractometer
3436 independent reflections
Radiation source: Enhance (Mo) X-ray Source3180 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
Detector resolution: 16.1978 pixels mm-1θmax = 26.4°, θmin = 3.3°
ω scansh = 1111
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
k = 1414
Tmin = 0.817, Tmax = 1.000l = 1919
10251 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.089H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0379P)2 + 0.290P]
where P = (Fo2 + 2Fc2)/3
3436 reflections(Δ/σ)max < 0.001
201 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = 0.15 e Å3
Crystal data top
C21H26OV = 1716.3 (3) Å3
Mr = 294.42Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 9.5760 (8) ŵ = 0.07 mm1
b = 11.3542 (11) ÅT = 180 K
c = 15.7852 (13) Å0.37 × 0.16 × 0.16 mm
Data collection top
Agilent Xcalibur Eos Gemini ultra
diffractometer
3436 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
3180 reflections with I > 2σ(I)
Tmin = 0.817, Tmax = 1.000Rint = 0.022
10251 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.089H-atom parameters constrained
S = 1.05Δρmax = 0.15 e Å3
3436 reflectionsΔρmin = 0.15 e Å3
201 parameters
Special details top

Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. CrysAlisPro (Agilent Technologies, 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 > 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C8A0.19916 (15)0.40195 (13)0.37785 (8)0.0301 (3)
H10.24700.47770.37130.036*
C80.13546 (16)0.40428 (13)0.46570 (9)0.0336 (3)
C70.00699 (18)0.44778 (15)0.47799 (10)0.0451 (4)
H70.02530.45190.53350.054*
C60.08850 (18)0.49016 (17)0.40973 (10)0.0472 (4)
H6A0.12600.56640.42560.057*
H6B0.16610.43580.40430.057*
C50.01461 (17)0.50089 (15)0.32443 (9)0.0401 (4)
H5A0.03660.57460.32280.048*
H5B0.08400.50290.27970.048*
C4A0.08624 (15)0.39923 (13)0.30807 (9)0.0304 (3)
C40.15939 (18)0.41743 (16)0.22242 (9)0.0426 (4)
H4B0.09030.41320.17760.051*
H4A0.20020.49560.22120.051*
C30.27356 (17)0.32686 (17)0.20516 (9)0.0437 (4)
H3A0.32060.34660.15260.052*
H3B0.23140.24980.19830.052*
C20.38162 (15)0.32205 (13)0.27753 (9)0.0314 (3)
H20.43440.39600.27760.038*
C10.31110 (15)0.30807 (13)0.36395 (8)0.0313 (3)
H1B0.26880.23060.36760.038*
H1A0.38090.31410.40830.038*
C90.48216 (15)0.22168 (13)0.25939 (9)0.0332 (3)
C100.60358 (16)0.24005 (13)0.20307 (9)0.0348 (3)
H100.65670.17420.18940.042*
C110.64329 (14)0.34209 (13)0.17044 (9)0.0321 (3)
H110.59320.40830.18710.039*
C120.75915 (15)0.36131 (13)0.11029 (8)0.0309 (3)
C130.82643 (17)0.27048 (15)0.06720 (10)0.0391 (4)
H130.80030.19280.07690.047*
C140.93184 (17)0.29534 (16)0.01017 (11)0.0463 (4)
H140.97670.23420.01800.056*
C150.97102 (17)0.41042 (17)0.00528 (11)0.0471 (4)
H151.04150.42680.04400.056*
C160.90527 (16)0.50077 (16)0.03690 (10)0.0422 (4)
H160.93150.57840.02680.051*
C170.80018 (15)0.47621 (14)0.09437 (9)0.0343 (3)
H170.75640.53780.12270.041*
C200.00546 (18)0.28311 (15)0.30817 (11)0.0445 (4)
H20A0.03120.26870.36380.067*
H20B0.06690.22000.29250.067*
H20C0.07010.28770.26830.067*
C180.22086 (18)0.36189 (18)0.53939 (9)0.0472 (4)
H18C0.16870.37200.59080.071*
H18A0.30580.40650.54260.071*
H18B0.24270.28000.53190.071*
O10.46109 (12)0.12334 (9)0.28773 (7)0.0471 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C8A0.0304 (7)0.0322 (7)0.0277 (7)0.0013 (6)0.0012 (6)0.0015 (6)
C80.0352 (8)0.0357 (8)0.0298 (7)0.0045 (7)0.0025 (6)0.0017 (6)
C70.0428 (9)0.0567 (10)0.0358 (8)0.0089 (8)0.0101 (7)0.0016 (7)
C60.0403 (9)0.0534 (10)0.0480 (9)0.0150 (8)0.0076 (7)0.0009 (8)
C50.0392 (8)0.0421 (8)0.0389 (8)0.0102 (8)0.0017 (7)0.0046 (7)
C4A0.0282 (7)0.0349 (8)0.0280 (7)0.0027 (6)0.0013 (6)0.0010 (6)
C40.0414 (9)0.0582 (10)0.0283 (7)0.0103 (8)0.0008 (6)0.0086 (7)
C30.0424 (9)0.0620 (11)0.0266 (7)0.0095 (8)0.0022 (7)0.0010 (7)
C20.0293 (7)0.0345 (8)0.0305 (7)0.0002 (6)0.0044 (6)0.0019 (6)
C10.0300 (7)0.0363 (8)0.0275 (7)0.0027 (7)0.0001 (6)0.0024 (6)
C90.0319 (7)0.0373 (8)0.0305 (7)0.0004 (7)0.0008 (6)0.0010 (7)
C100.0328 (8)0.0348 (8)0.0367 (8)0.0064 (6)0.0035 (6)0.0037 (7)
C110.0289 (7)0.0380 (8)0.0294 (7)0.0036 (7)0.0000 (6)0.0026 (6)
C120.0258 (7)0.0393 (8)0.0277 (7)0.0007 (6)0.0042 (6)0.0005 (6)
C130.0385 (8)0.0403 (9)0.0384 (8)0.0007 (7)0.0038 (7)0.0042 (7)
C140.0401 (9)0.0569 (11)0.0420 (9)0.0041 (8)0.0081 (7)0.0113 (8)
C150.0338 (8)0.0683 (11)0.0392 (9)0.0040 (9)0.0088 (7)0.0015 (8)
C160.0334 (8)0.0469 (9)0.0463 (9)0.0051 (8)0.0005 (7)0.0083 (8)
C170.0273 (7)0.0386 (8)0.0368 (8)0.0036 (7)0.0016 (6)0.0006 (7)
C200.0351 (8)0.0450 (9)0.0535 (10)0.0043 (7)0.0060 (8)0.0080 (8)
C180.0429 (9)0.0710 (12)0.0278 (7)0.0021 (9)0.0022 (7)0.0029 (8)
O10.0494 (7)0.0350 (6)0.0568 (7)0.0033 (5)0.0149 (6)0.0062 (5)
Geometric parameters (Å, º) top
C8A—C81.5153 (19)C1—H1B0.9700
C8A—C11.528 (2)C1—H1A0.9700
C8A—C4A1.5439 (19)C9—O11.2197 (17)
C8A—H10.9800C9—C101.478 (2)
C8—C71.340 (2)C10—C111.324 (2)
C8—C181.501 (2)C10—H100.9300
C7—C61.493 (2)C11—C121.4765 (19)
C7—H70.9300C11—H110.9300
C6—C51.526 (2)C12—C171.385 (2)
C6—H6A0.9700C12—C131.393 (2)
C6—H6B0.9700C13—C141.382 (2)
C5—C4A1.527 (2)C13—H130.9300
C5—H5A0.9700C14—C151.381 (3)
C5—H5B0.9700C14—H140.9300
C4A—C201.529 (2)C15—C161.376 (2)
C4A—C41.537 (2)C15—H150.9300
C4—C31.525 (2)C16—C171.383 (2)
C4—H4B0.9700C16—H160.9300
C4—H4A0.9700C17—H170.9300
C3—C21.542 (2)C20—H20A0.9600
C3—H3A0.9700C20—H20B0.9600
C3—H3B0.9700C20—H20C0.9600
C2—C91.519 (2)C18—H18C0.9600
C2—C11.5304 (18)C18—H18A0.9600
C2—H20.9800C18—H18B0.9600
C8—C8A—C1115.22 (12)C3—C2—H2108.4
C8—C8A—C4A111.80 (11)C8A—C1—C2111.42 (11)
C1—C8A—C4A112.03 (11)C8A—C1—H1B109.3
C8—C8A—H1105.6C2—C1—H1B109.3
C1—C8A—H1105.6C8A—C1—H1A109.3
C4A—C8A—H1105.6C2—C1—H1A109.3
C7—C8—C18120.41 (14)H1B—C1—H1A108.0
C7—C8—C8A120.57 (14)O1—C9—C10118.67 (13)
C18—C8—C8A118.96 (13)O1—C9—C2120.85 (13)
C8—C7—C6125.23 (14)C10—C9—C2120.39 (12)
C8—C7—H7117.4C11—C10—C9125.69 (13)
C6—C7—H7117.4C11—C10—H10117.2
C7—C6—C5112.24 (13)C9—C10—H10117.2
C7—C6—H6A109.2C10—C11—C12126.55 (13)
C5—C6—H6A109.2C10—C11—H11116.7
C7—C6—H6B109.2C12—C11—H11116.7
C5—C6—H6B109.2C17—C12—C13118.51 (14)
H6A—C6—H6B107.9C17—C12—C11117.97 (13)
C6—C5—C4A112.47 (13)C13—C12—C11123.50 (14)
C6—C5—H5A109.1C14—C13—C12120.31 (16)
C4A—C5—H5A109.1C14—C13—H13119.8
C6—C5—H5B109.1C12—C13—H13119.8
C4A—C5—H5B109.1C15—C14—C13120.45 (16)
H5A—C5—H5B107.8C15—C14—H14119.8
C5—C4A—C20109.37 (12)C13—C14—H14119.8
C5—C4A—C4109.61 (12)C16—C15—C14119.72 (15)
C20—C4A—C4110.34 (13)C16—C15—H15120.1
C5—C4A—C8A107.89 (12)C14—C15—H15120.1
C20—C4A—C8A111.77 (12)C15—C16—C17120.01 (16)
C4—C4A—C8A107.80 (11)C15—C16—H16120.0
C3—C4—C4A113.16 (13)C17—C16—H16120.0
C3—C4—H4B108.9C16—C17—C12121.01 (15)
C4A—C4—H4B108.9C16—C17—H17119.5
C3—C4—H4A108.9C12—C17—H17119.5
C4A—C4—H4A108.9C4A—C20—H20A109.5
H4B—C4—H4A107.8C4A—C20—H20B109.5
C4—C3—C2111.86 (13)H20A—C20—H20B109.5
C4—C3—H3A109.2C4A—C20—H20C109.5
C2—C3—H3A109.2H20A—C20—H20C109.5
C4—C3—H3B109.2H20B—C20—H20C109.5
C2—C3—H3B109.2C8—C18—H18C109.5
H3A—C3—H3B107.9C8—C18—H18A109.5
C9—C2—C1111.70 (12)H18C—C18—H18A109.5
C9—C2—C3108.19 (12)C8—C18—H18B109.5
C1—C2—C3111.58 (12)H18C—C18—H18B109.5
C9—C2—H2108.4H18A—C18—H18B109.5
C1—C2—H2108.4

Experimental details

Crystal data
Chemical formulaC21H26O
Mr294.42
Crystal system, space groupOrthorhombic, P212121
Temperature (K)180
a, b, c (Å)9.5760 (8), 11.3542 (11), 15.7852 (13)
V3)1716.3 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.37 × 0.16 × 0.16
Data collection
DiffractometerAgilent Xcalibur Eos Gemini ultra
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.817, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
10251, 3436, 3180
Rint0.022
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.089, 1.05
No. of reflections3436
No. of parameters201
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.15, 0.15

Computer programs: CrysAlis PRO (Agilent, 2010), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

 

Acknowledgements

We thank the National Center of Scientific and Technological Research (CNRST) for supporting our scientific research.

References

First citationAgilent (2010). CrysAlis PRO . Agilent Technologies Ltd, Yarnton, England.  Google Scholar
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