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Total Synthesis of Terpenoids Employing a "Benzannulation of Carvone" Strategy: Synthesis of (-)-Crotogoudin.

ABSTRACT: Carvone is a sustainable and readily available starting material for organic synthesis. Herein, we present the syntheses of various natural product scaffolds that rely on a novel benzannulation involving the ?-methyl group (C-10) of carvone to afford a versatile tetralin. The utility of our synthetic approach is highlighted by its application to a short synthesis of the ent-3,4-seco-atisane diterpenoid (-)-crotogoudin. The 13-step enantiospecific synthesis features a regioselective double oxidative dearomatization, a Diels-Alder cycloaddition with ethylene gas (to construct the bicyclo[2.2.2]octane framework), and a final acid-mediated lactonization. The versatility of this benzannulation strategy is demonstrated by its utility in the preparation of the carbon skeleton of ent-3,4-seco-abietane diterpenoids using an intramolecular oxidative dearomatization.

SUBMITTER: Finkbeiner P

PROVIDER: S-EPMC6309435 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Total Synthesis of Terpenoids Employing a "Benzannulation of Carvone" Strategy: Synthesis of (-)-Crotogoudin.

Finkbeiner Peter P Murai Kenichi K Röpke Michael M Sarpong Richmond R

Journal of the American Chemical Society 20170815 33

Carvone is a sustainable and readily available starting material for organic synthesis. Herein, we present the syntheses of various natural product scaffolds that rely on a novel benzannulation involving the α-methyl group (C-10) of carvone to afford a versatile tetralin. The utility of our synthetic approach is highlighted by its application to a short synthesis of the ent-3,4-seco-atisane diterpenoid (-)-crotogoudin. The 13-step enantiospecific synthesis features a regioselective double oxidat ...[more]

PMID: 28763218

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