| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1350764 | Tetrahedron: Asymmetry | 2006 | 5 Pages |
The synthesis of the trans-p-menthan-5-ol (±)-1 was carried out by Diels–Alder cycloaddition of 3-keto-1-butenyl-acetate 3 with isoprene followed by Wittig methylenation. PS lipase resolution of the alcohol afforded acetate (−)-5 with 98% ee, which was hydrolysed to give (−)-1. Alternatively, enzymatic hydrolysis of a keto ester followed by Wittig methylenation and hydrolysis afforded the same alcohol with an ee of 86%. The cis-p-menthan-5-ol (−)-2 was obtained by Swern oxidation of (−)-1, followed by diastereoselective reduction with L-Selectride without lost of enantiomeric excess.
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1-((1R,6R)-6-Hydroxy-4-methylcyclohex-3-enyl)ethanoneC9H14O2[α]D20=-158.4Source of chirality: enzymatic resolutionEe = 86%Absolute configuration: 1R,6R
(1R,6R)-6-Acetyl-3-methylcyclohex-3-enyl acetateC11H16O3[α]D20=131.8Source of chirality: enzymatic resolutionEe = 86%Absolute configuration: 1R,6R
(1R,6S)-3-Methyl-6-(prop-1-en-2-yl)cyclohex-3-enyl acetateC12H18O2[α]D20=-29.3Ee = 98%Source of chirality: enzymatic resolutionAbsolute configuration: 1R,6S
(1R,6S)-3-Methyl-6-(prop-1-en-2-yl)cyclohex-3-enolC10H16O[α]D20=-53.0Source of chirality: enzymatic resolutionEe = 98%Absolute configuration: 1R,6S
(S)-3-Methyl-6-(prop-1-en-2-yl)cyclohex-3-enoneC10H14O[α]D20=-127.2Source of chirality: enzymatic resolutionEe = 98%Absolute configuration: 1S
(1S,6S)-3-Methyl-6-(prop-1-en-2-yl)cyclohex-3-enolC10H16O[α]D20=-5.1Source of chirality: enzymatic resolutionEe = 98%Absolute configuration: 1S,6S
