Article ID Journal Published Year Pages File Type
1349885 Tetrahedron: Asymmetry 2005 5 Pages PDF
Abstract

An enantiospecific approach to a functionalised carbon framework of the sesquiterpenes, cyperanes, starting from the monoterpene (R)-carvone has been accomplished. A combination of a Claisen rearrangement, intramolecular diazo ketone cyclopropanation and regiospecific cyclopropane ring cleavage has been exploited for the stereo and regiospecific generation of the vicinal stereogenic quaternary carbon atoms.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide

(5S)-3-Ethyl-5-isopropenyl-2-methylcyclohex-2-enoneC12H18O[α]D25=+5 (c 1, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (5S)

(1S,5S)-3-Ethyl-5-isopropenyl-2-methylcyclohex-2-enolC12H20O[α]D24=+31.5 (c 2, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,5S)

Ethyl-2-[(1S,5R)-1-ethyl-5-isopropenyl-2-methylcyclohex-2-enyl]acetateC16H26O2[α]D25=+10 (c 1, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,5R)

(1R,2R,4R,6S,9S)-6-Ethyl-4-isopropenyl-1-methyltricyclo[4.3.0.02,9]nonan-8-oneC15H20O[α]D23=+81.5 (c 2, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,2R,4R,6S,9S)

(1S,3R,6R)-1-Ethyl-3-isopropenyl-6-methylbicyclo[4.3.0]nonan-8-oneC15H24O[α]D28=-47.5 (c 1.2, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,3R,6R)

(5S)-3-Benzyl-5-isopropenyl-2-methylcyclohex-2-enoneC17H20O[α]D26=+37.1 (c 3.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (5S)

(1S,5S)-3-Benzyl-5-isopropenyl-2-methylcyclohex-2-enolC17H22O[α]D25=+20.9 (c 5.5, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,5S)

Ethyl (1R,5R)-1-benzyl-5-isopropenyl-2-methylcyclohex-2-enylacetateC21H28O2[α]D25=-10.0 (c 0.4, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,5R)

(1R,2R,4R,6R,9S)-6-Benzyl-4-isopropenyl-1-methyltricyclo[4.3.0.02,9]nonan-8-oneC20H24O[α]D22=+64.5 (c 1.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,2R,4R,6R,9S)

(1R,3R,6R)-1-Benzyl-3-isopropenyl-6-methylbicyclo[4.3.0]nonan-8-oneC20H26O[α]D22=-55 (c 1.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,3R,6R)

(1R,3R,6R)-1-Benzyl-3-isopropyl-6-methylbicyclo[4.3.0]nonan-8-oneC20H28O[α]D26=-42.5 (c 1.6, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,3R,6R)

Methyl [(1S,3R,6R)-3-isopropyl-6-methyl-8-oxobicyclo[4.3.0]non-1-yl]acetateC16H26O[α]D24=-40 (c 0.5, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,3R,6R)

(1R,5S)-3-Benzyl-5-isopropenyl-2-methylcyclohex-2-enyl benzoateC24H26O2[α]D23=+124 (c 1.4, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,5S)

(1R,5S)-3-Benzyl-5-isopropenyl-2-methylcyclohex-2-enolC27H22O[α]D23=+90.2 (c 0.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,5S)

Ethyl 2-[(1S,5R)-1-benzyl-5-isopropenyl-2-methylcyclohex-2-enyl]acetateC21H28O2[α]D27=+18 (c 0.5, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,5R)

(1S,2S,4R,6S,9R)-6-Benzyl-4-isopropenyl-1-methyltricyclo[4.3.0.02,9]nonan-8-oneC20H24O[α]D22=-54.5 (c 1.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,2S,4R,6S,9R)

(1S,3R,6S)-1-Benzyl-3-isopropenyl-6-methylbicyclo[4.3.0]nonan-8-oneC20H26O[α]D26=-62.5 (c 0.8, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,3R,6S)

(1S,3R,6S)-1-Benzyl-3-isopropyl-6-methylbicyclo[4.3.0]nonan-8-oneC20H28O[α]D25=-70 (c 0.5, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1S,3R,6S)

Methyl [(1R,3R,6S)-3-isopropenyl-6-methyl-8-oxobicyclo[4.3.0]non-1-yl]acetateC16H26O[α]D23=-57 (c 1, CHCl3)Source of chirality: (R)-carvoneAbsolute configuration: (1R,3R,6S)

Related Topics
Physical Sciences and Engineering Chemistry Inorganic Chemistry
Authors
, ,