13834-71-4Relevant academic research and scientific papers
Chemoenzymatic preparation of the p-menth-1,5-dien-9-ol stereoisomers and their use in the enantiospecific synthesis of natural p-menthane monoterpenes
Serra, Stefano,Nobile, Igor
experimental part, p. 1455 - 1463 (2011/11/12)
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 (1R)- or (1S)-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.
Chemical Tranformation of Terpenoids. V. Acidic Conversions of 10-Hydroxygeraniol and 10-Hydroxynerol Derivatives Leading to Cyclic Monoterpenoids
Kitagawa, Isao,Tsujii, Shinji,Nishikawa, Fumiko,Shibuya, Hirotaka
, p. 2639 - 2651 (2007/10/02)
Acid treatment of 1-O-acetyl-10-hydroxygeraniol (5a), 1-O-methyl-10-hydroxygeraniol (5b), 1-O-acetyl-10-hydroxynerol (6a), and 1-O-methyl-10-hydroxynerol (6b) was investigated under various conditions.It was found that treatment of 5a and 6a with HCOOH gave menth-1-ene-8,9-diol (7), while treatment of 5a, 5b, 6a, or 6b with BF3-etherate in CH2Cl2 furnished two menthofuran-type compounds (9, 10) and two bicyclooct-2-ene derivatives (17, 24).Both 9 and 10 were successfully converted to menthofuran (16) and 17 was converted to a bicyclooctenone derivative (23) which was a key intermediate for a synthesis of juvabione (27).Keywords - geraniol; nerol; 10-hydroxygeraniol; 10-hydroxynerol; 10-hydroxygeraniol derivative; 10-hydroxynerol derivative; uroterpenol; menthofuran; bicyclooct-2-ene derivative
