13918-47-3Relevant academic research and scientific papers
An Improved Synthesis of Homochiral Octalones from (-)-Carvone
Tenius, Beatriz S. M.,Oliveira, Eduardo R. de,Ferraz, Helena M. C.
, p. 633 - 636 (2007/10/02)
A novel diastereoselective route to octalones 3 and 4 has been developed.The key step involves an asymmetric Michael addition of the corresponding chiral imine, derived from R-(+)-dihydrocarvone, to methyl vinyl ketone.
THE CONVERSION OF (-)- AND (+)-DIHYDROCARVONE INTO CHIRAL INTERMEDIATES FOR THE SYNTHESIS OF (-)-POLYGODIAL, (-)-WARBURGANAL AND (-)-MUZIGADIAL
Jansen, Ben. J. M.,Kreuger, Jacoba A.,Groot, Aede De
, p. 1447 - 1452 (2007/10/02)
(-)-Dihydrocarvone was converted into (-)-(4aR,8aR)-3,4,4a,5,6,7,8,8a-octahydro-4a,8,8,trimethylnaphthalene-2(H)-one (1) via an efficient route in which a Wolff-Kishner reduction, accompanied with a double bond isomerisation brought on a major simplification.Ketone 1 is a suitable intermediate for the syntheses of the insectantifeedants (-)-polygodial and (-)-warburganal. (+)-Dihydrocarvone was converted into (+)-(4aR,7S,8aR)-4a,7-dimethyl-8-methylene-3,4,4a,5,6,7,8,8a-octahydronaphthalene-2(1H)-one (2), an intermediate ketone for synthesis of (-)-muzigadial.
Conformation of Epi-α-cyperone and Related Enones
Huffman, John W.,Swain, William E.,Jacobus, John,McPhail, Andrew T.
, p. 3088 - 3096 (2007/10/02)
The conformations of epi-α-cyperone (10-epieudesma-4,11-dien-3-one, 2) and its dihydro and 14-nor analogues (4 and 15, respectively) have been investigated by a combination of lanthanide induced shift reagent 1H NMR, 13C NMR, and high field 1H NMR techniques.Comparison of these spectral data with those of the normal eudesmane derivatives, α-cyperone (1), dihydro-α-cyperone (3), and 14-noreudesm-4-en-3-one (14) clearly shows that the conformations of all six enones are similar with a half-chair conformation for ring A and a chair conformation for ring B.11-Methyl-10-epieudesm-4-en-3-one (5) was prepared either from 5α-hydroxy-10-epieudesm-11-en-3-one (6) or by the Robinson annulation of 2-methyl-5-tert-butylcyclohexanone with ethyl vinyl ketone. 14-Nor-11-methyl-10-epieidesm-4-en-3-one (15) was prepared by the annulation of 2-methyl-5-tert-butylcyclohexanone with methyl vinyl ketone.The 13C lanthanide induced shift and high-field 1H NMR spectra of enones 5 and 13 indicate that these molecules are not conformationally homogeneous.An X-ray structure determination of the oxime of enone 5 showed that in the solid state ring A exists in a envelope conformation and ring B in a twist conformation with a ψ-equatorial tert-butyl group.Crystals of the oxime of 5 belong to the triclinic system, space group P1, with a = 6.290(3) Angstroem, b = 12.010(5) Angstroem, c = 10.341(5) Angstroem, α = 85.20(2) deg, β = 95.56(2) deg, γ = 101.09(2) deg, and Z=2.Atomic positional and thermal parameters were refined by least-squares calculation to R = 0.068 over 1609 observed reflections measured by a diffractometer.
