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Interrupted carbonyl-olefin metathesis via oxygen atom transfer.

ABSTRACT: Some of the simplest and most powerful carbon-carbon bond forming strategies take advantage of readily accessible ubiquitous motifs: carbonyls and olefins. Here we report a fundamentally distinct mode of reactivity between carbonyls and olefins that differs from established acid-catalyzed carbonyl-ene, Prins, and carbonyl-olefin metathesis reaction paths. A range of epsilon, zeta-unsaturated ketones undergo Brønsted acid-catalyzed intramolecular cyclization to provide tetrahydrofluorene products via the formation of two new carbon-carbon bonds. Theoretical calculations and accompanying mechanistic studies suggest that this carbocyclization reaction proceeds through the intermediacy of a transient oxetane formed by oxygen atom transfer. The complex polycyclic frameworks in this product class appear as common substructures in organic materials, bioactive natural products, and recently developed pharmaceuticals.

SUBMITTER: Ludwig JR

PROVIDER: S-EPMC6983304 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Interrupted carbonyl-olefin metathesis via oxygen atom transfer.

Ludwig Jacob R JR Watson Rebecca B RB Nasrallah Daniel J DJ Gianino Joseph B JB Zimmerman Paul M PM Wiscons Ren A RA Schindler Corinna S CS

Science (New York, N.Y.) 20180901 6409

Some of the simplest and most powerful carbon-carbon bond forming strategies take advantage of readily accessible ubiquitous motifs: carbonyls and olefins. Here we report a fundamentally distinct mode of reactivity between carbonyls and olefins that differs from established acid-catalyzed carbonyl-ene, Prins, and carbonyl-olefin metathesis reaction paths. A range of epsilon, zeta-unsaturated ketones undergo Brønsted acid-catalyzed intramolecular cyclization to provide tetrahydrofluorene products ...[more]

PMID: 30262500

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