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Platinum-Catalyzed ?,?-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 ?,?-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 ?,?-unsaturated carbene reaction manifold.

SUBMITTER: Huynh KQ

PROVIDER: S-EPMC5369019 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Platinum-Catalyzed α,β-Unsaturated Carbene Formation in the Formal Syntheses of Frondosin B and Liphagal.

Huynh Khoi Q KQ Seizert Curtis A CA Ozumerzifon Tarik J TJ Allegretti Paul A PA Ferreira Eric M EM Ferreira Eric M EM

Organic letters 20161220 1

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 cata ...[more]

PMID: 27997203

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