This thesis describes the total syntheses of the sesterterpenoid (±)-palauolide (55) and the diterpenoids (±)-isolinaridiol (64) and (±)-isolinaridiol diacetate (61).
In the total synthesis of (±)-palauolide, the decalin substructure was constructed by a copper(I) bromide-dimethyl sulfide catalyzed addition of the Grignard reagent 40 to 3,6-dimethyl-2-cyclohexen-1-one (115), followed by intramolecular alkylation of the resultant chloro ketone 121. The resultant annulation product 114 was converted into the nitrile 112, which was stereoselectively alkylated with ICH₂CH₂CH₂OCH₂OCH₃ to provide the nitrile 173. The latter substance was transformed via a series of reactions into compound 175 which was converted
into the α β-unsaturated aldehyde 107. Julia olefination of 107 with the lithium salt of the sulfone 223 provided stereoselectively the triene 216, which was photooxygenated to provide (±)-palauolide (55).
In the total syntheses of (±)-isolinaridiol (64) and (±)-isolinaridiol
diacetate (61), the bicyclic substance 276 was prepared by following the chemistry developed in the synthesis of (±)-palauolide (55). Conversion of 276 into the aldehyde 234, followed by treatment of this material, under carefully defined conditions, with the anion of the Z-lactone phosphonate 261, provided the Z lactone 279 as the major product. Diisobutylaluminum hydride reduction of 279 yielded (±)-isolinaridiol
(64). Bis-acetylation of the latter material provided (±) -isolinaridiol diacetate (61). [Formula Omitted] / Science, Faculty of / Chemistry, Department of / Graduate
| Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/29446 |
| Date | January 1988 |
| Creators | Wai, John Sui Man |
| Publisher | University of British Columbia |
| Source Sets | University of British Columbia |
| Language | English |
| Detected Language | English |
| Type | Text, Thesis/Dissertation |
| Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
Page generated in 0.0019 seconds