| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345417 | Tetrahedron: Asymmetry | 2013 | 7 Pages |
The combined use of the Sharpless asymmetric epoxidation, a number of stereospecific chemical transformations, and the 3,5-hexadienoic acid benzannulation protocol allowed us to devise a new, divergent, and stereoselective approach to terpenes with a chiral tertiary hydroxyl group at the ortho-position of a phenol functional group. Accordingly, the natural occurring enantiomeric forms of the bisabolane sesquiterpenes (+)-curcutetraol, (+)-sydonol, (+)-sydonic acid, and (+)-7-O-methylsydonic acid were synthesized with high enantiomeric purity starting from geraniol. The latter two acids were prepared in enantioenriched form for the first time.
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(S)-4,8-Dimethylnon-7-en-2-yne-1,4-diolC11H18O2ee = 95%[α]D20=-11.9 (c 1.9, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S)-4,8-Dimethylnon-2-yne-1,4-diolC11H20O2ee = 95%[α]D20=+2.6 (c 1.2, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-4,8-Dimethylnona-2,7-diene-1,4-diolC11H20O2ee = 95%[α]D20=+4.4 (c 2, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-4,8-Dimethylnon-2-ene-1,4-diolC11H22O2ee = 95%[α]D20=+6.8 (c 4, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-4,8-Dimethyl-4-(triethylsilyloxy)nona-2,7-dien-1-olC17H34O2Siee = 95%[α]D20=-1.5 (c 2.1, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-4,8-Dimethyl-4-(triethylsilyloxy)non-2-en-1-olC17H36O2Siee = 95%[α]D20=-3.1 (c 2.6, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-tert-Butyl(4-methoxy-4,8-dimethylnon-2-enyloxy)diphenylsilaneC28H42O2Siee = 95%[α]D20=+2.5 (c 0.6, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,E)-4-Methoxy-4,8-dimethylnon-2-en-1-olC12H24O2ee = 95%[α]D20=-11.6 (c 2, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (4S)
(S,3E,5E)-3-(Ethoxycarbonyl)-7,11-dimethyl-7-(triethylsilyloxy)dodeca-3,5,10-trienoic acidC23H40O5Siee = 95%[α]D20=+5.4 (c 2.7, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (7S)
(S,3E,5E)-3-(Ethoxycarbonyl)-7,11-dimethyl-7-(triethylsilyloxy)dodeca-3,5-dienoic acidC23H42O5Siee = 95%[α]D20=+6.5 (c 2.1, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (7S)
(S,3E,5E)-3-(ethoxycarbonyl)-7-methoxy-7,11-dimethyldodeca-3,5-dienoic acidC18H30O5ee = 95%[α]D20=-7.6 (c 2.3, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (7S)
(S)-Ethyl 3-hydroxy-4-(6-methyl-2-(triethylsilyloxy)hept-5-en-2-yl)benzoateC23H38O4Siee = 95%[α]D20=+15.4 (c 1.8, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-Ethyl 3-hydroxy-4-(6-methyl-2-(triethylsilyloxy)heptan-2-yl)benzoateC23H40O4Siee = 95%[α]D20=+3.9 (c 2.3, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-Ethyl 3-hydroxy-4-(2-methoxy-6-methylheptan-2-yl)benzoateC18H28O4ee = 95%[α]D20=+15.7 (c 2.4, CHCl3)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-2-(2-Hydroxy-4-(hydroxymethyl)phenyl)-6-methylheptane-2,6-diolC15H24O4ee = 95%[α]D20=+6.3 (c 2.2, MeOH)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-2-(2-Hydroxy-6-methylheptan-2-yl)-5-(hydroxymethyl)phenolC15H24O3ee = 95%[α]D20=+5.8 (c 2, MeOH)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-3-Hydroxy-4-(2-hydroxy-6-methylheptan-2-yl)benzoic acidC15H22O4ee = 95%[α]D20=+1.5 (c 1.4, MeOH)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
(S)-3-Hydroxy-4-(2-methoxy-6-methylheptan-2-yl)benzoic acidC16H24O4ee = 95%[α]D20=+3.9 (c 1.9, MeOH)Source of chirality: Sharpless asymmetric epoxidationAbsolute configuration: (2S)
