S. Serra, Igor Nobile
Jul 15, 2011
Citations
0
Influential Citations
14
Citations
Journal
Tetrahedron-asymmetry
Abstract
Abstract A study on the preparation and synthetic exploitation of the isomeric forms of p -menth-1,5-dien-9-ol is reported. The latter alcohols were prepared in high enantiomeric purity from the easily available enantiomers of carvone. Thus, a chemoenzymatic procedure based on lipase-mediated acetylation, allowed the separation of their diastereoisomeric forms. Moreover, the purity of the chiral building blocks obtained was improved by fractional crystallisation of their 3,5-dinitrobenzoyl derivatives. A number of synthetic applications have also been described. The stereospecific cyclisation of the isomerically pure dienic alcohols gave the isomeric forms of the terpenes dill and epi -dill ether, which were hydrogenated diastereoselectively to the corresponding (1 R )- or (1 S )-derivatives depending on the catalyst used. The oxidation of the latter ethers turned out to be stereoselective, affording either the corresponding p -menthan-9-oic lactone or the keto-acid derivatives depending on the starting isomer used.