Preparation and Odor Evaluation of Both Enantiomers of 3,4,4aα,5,6,7,8,8aβ‐Octahydro‐5,5,8aβ‐trimethyl‐2(1 H )‐naphthalenone and 1,2α,3,4,4aβ,5,6,7,8,8aβ‐Decahydro‐5,5,8aβ‐trimethyl‐2β‐naphthalenyl Acetate, Four Woody Odorants

The enantiomeric decahydro‐2‐naphthalenols (+)‐ 5 and (−)‐5 were prepared by enantioselective hydrolysis of the racemic chloroacetate (±)‐ 2 catalyzed by porcine pancreatic lipase, and converted to the corresponding acetates (+)‐ 1 and (−)‐ 1 and ketones (+)‐ 6 and (−)‐ 6 . The absolute configurations of the ketones, alcohols, and acetates were established by chemical correlation with natural manool ((+)‐ 7 ) by making use of a retro ‐ene cleavage reaction of the known manool degradation product 8 to (−)‐ 6 . A distinct odour difference between the two enantiomers of each pair (+)‐ 1 /(−)‐ 1 and (+)‐ 6 /(−)‐ 6 has been found.