Syntheses of (±)-Z-Geissoschizol, (±)-3-epi-Z-Geissoschizol, (±)-Corynantheidol, (±)-Dihydrocorynantheol, (±)-3-epi-Dihydrocorynantheol and the Corresponding Corynan-17-oic Acid Methyl Esters
作者:Mauri Lounasmaa、Reija Jokela、Birgit Tirkkonen、Jari Miettinen、Minna Halonen
DOI:10.3987/com-91-5922
日期:——
The utility of the Claisen rearrangement using carefully separated, diastereoisomeric allylic alcohols (1a) and (1b) in the preparation of (+/-)-Z-geissoschizol (4a), (+/-)-3-epi-Z-geissoschizol (4b), (+/-)-corynantheidol (7a), (+/-)-dihydrocorynantheol (8a), (+/-)-3-epi-dihydrocorynantheol (8b) and the corresponding corynan-17-oic acid methyl esters (3a, 3b, 5a, 6a and 6b) is shown. Special attention is paid to the stereochemical outcome of catalytic (PtO2) hydrogenation of the C(20) Z-ethylidene side chain.