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Utilization of the Thorpe-Ingold Effect in the Synthesis of Cyclooctanoid Ring Systems via Anionic 6-exo-dig Cyclization/Claisen Rearrangement Sequence.

ABSTRACT: We demonstrate a facile approach for the synthesis of gem-disubstituted cyclooctanoids, a motif found in several biologically active compounds. Appropriately substituted 1-alkenyl-5-pentyn-1-ols bearing gem-dialkyl substituents at either the C2, C3, or C4 position serve as useful precursors to a number of cyclooct-4-enone derivatives via a tandem, microwave-assisted oxyanionic 6-exo-dig cyclization/Claisen rearrangement reaction. gem-Dialkyl activation is necessary for these reactions to occur, as unactivated 1-alkenyl-5-pentyn-1-ols fail to undergo 6-exo-dig cyclization under the conditions employed. Further application of the methodology to the corresponding gem-dialkoxy system was also explored to facilitate access to more complex carbocycles.

SUBMITTER: DeLomba WC

PROVIDER: S-EPMC8588887 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Synthesis of seven-membered carbocyclic rings via a microwave-assisted tandem oxyanionic 5-exo dig cyclization-claisen rearrangement process.

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Alkene Isomerization Revitalizes the Coates-Claisen Rearrangement.

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