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Biomimetic Total Synthesis of (±)-Griffipavixanthone via a Cationic Cycloaddition-Cyclization Cascade.

ABSTRACT: We report the concise, biomimetic total synthesis of the dimeric, Diels-Alder natural product griffipavixanthone from a readily accessible prenylated xanthone monomer. The key step utilizes a novel intermolecular [4+2] cycloaddition-cyclization cascade between a vinyl p-quinone methide and an in situ generated isomeric diene promoted by either Lewis or Brønsted acids. Experimental and computational studies of the reaction pathway suggest that a stepwise, cationic Diels-Alder cycloaddition is operative.

SUBMITTER: Reichl KD

PROVIDER: S-EPMC5718057 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Biomimetic Total Synthesis of (±)-Griffipavixanthone via a Cationic Cycloaddition-Cyclization Cascade.

Reichl Kyle D KD Smith Michael J MJ Song Min K MK Johnson Richard P RP Porco John A JA

Journal of the American Chemical Society 20171002 40

We report the concise, biomimetic total synthesis of the dimeric, Diels-Alder natural product griffipavixanthone from a readily accessible prenylated xanthone monomer. The key step utilizes a novel intermolecular [4+2] cycloaddition-cyclization cascade between a vinyl p-quinone methide and an in situ generated isomeric diene promoted by either Lewis or Brønsted acids. Experimental and computational studies of the reaction pathway suggest that a stepwise, cationic Diels-Alder cycloaddition is ope ...[more]

PMID: 28942643

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