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Syntheses of Amorfrutins and Derivatives via Tandem Diels-Alder and Anionic Cascade Approaches.

ABSTRACT: We describe two complementary approaches based on a convergent [4+2] logic toward the synthesis of amorfrutins, cannabinoids, and related plant metabolites. An anionic cascade cyclization employing β-methoxycrotonates and β-chloro-α,β-unsaturated esters yielded amorfrutins in four linear steps and demonstrated utility of β-alkoxycrotonate-derived nucleophiles as functional equivalents of β-ketoester-derived dianions. Analogously, tandem Diels-Alder/retro-Diels-Alder cycloaddition of dimedone-derived bis(trimethylsiloxy)-dienes and α,β-alkynyl ester dienophiles provided facile access to resorcinol precursors of amorfrutins and cannabinoids, avoiding late-stage installation of prenyl or geranyl moieties as in previous approaches.

SUBMITTER: Curtis BJ

PROVIDER: S-EPMC8594413 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Syntheses of Amorfrutins and Derivatives via Tandem Diels-Alder and Anionic Cascade Approaches.

Curtis Brian J BJ Micikas Robert J RJ Burkhardt Russell N RN Smith Rubin A RA Pan Judy Y JY Jander Katrina K Schroeder Frank C FC

The Journal of organic chemistry 20210304 16

We describe two complementary approaches based on a convergent [4+2] logic toward the synthesis of amorfrutins, cannabinoids, and related plant metabolites. An anionic cascade cyclization employing β-methoxycrotonates and β-chloro-α,β-unsaturated esters yielded amorfrutins in four linear steps and demonstrated utility of β-alkoxycrotonate-derived nucleophiles as functional equivalents of β-ketoester-derived dianions. Analogously, tandem Diels-Alder/retro-Diels-Alder cycloaddition of dimedone-der ...[more]

PMID: 33661630

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