title: Platinum-Catalyzed α,β-Unsaturated Carbene Formation in the Formal Syntheses of Frondosin B and Liphagal.
abstract: Formal syntheses of tetracyclic terpenoids frondosin B and liphagal are described. Both synthetic routes rely on the use of platinum-catalyzed α,β-unsaturated carbene formation for the key C-C bond forming transformations. The successful route toward frondosin B utilizes a formal (4 + 3) cycloaddition, while the liphagal synthesis features the vinylogous addition of an enol nucleophile as a key step. Both synthetic routes are discussed, revealing insights into structural requirements in the catalytic α,β-unsaturated carbene reaction manifold.
authors.affiliation: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Khoi Q
authors.initials: KQ
authors.lastname: Huynh
authors.affiliation: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Curtis A
authors.initials: CA
authors.lastname: Seizert
authors.affiliation: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Tarik J
authors.initials: TJ
authors.lastname: Ozumerzifon
authors.affiliation: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Allegretti
authors.affiliation: Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States.
authors.forename: Eric M
authors.identifier: 0000-0001-9412-0713
authors.initials: EM
authors.lastname: Ferreira
mesh_terms: D002384:Catalysis; D061565:Cycloaddition Reaction; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010636:Phenols / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D013237:Stereoisomerism; D013729:Terpenes / Q000138:chemical synthesis*
chemical_list: D006576:Heterocyclic Compounds, 4 or More Rings; D010636:Phenols; D013729:Terpenes; C421322:frondosin B; C513880:liphagal; C030011:carbene; D010984:Platinum; D008697:Methane