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Indium-Mediated 2-Oxonia Cope Rearrangement of 1,4-Dienols to 1,3-Dienols.

ABSTRACT: An indium-mediated isomerization of 1,4-dienols to 1,3-dienols is described. This procedure consists of the addition of pentadienylindium, in a protic solvent, to aldehydes giving the kinetic ?-allylation product in high yields. The subsequent conversion of this ?-allylation product to its thermodynamic 1,3-dienol ?-isomer can be achieved by its exposure to indium triflate in the presence of a substoichiometric amount of aldehyde at room temperature. This transformation exhibited moderate to good substrate scope and has been shown to proceed by a 2-oxonia Cope rearrangement.

SUBMITTER: Capel NJ

PROVIDER: S-EPMC6648455 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Indium-Mediated 2-Oxonia Cope Rearrangement of 1,4-Dienols to 1,3-Dienols.

Capel Natalie J NJ Lindley Martin R MR Pritchard Gareth J GJ Kimber Marc C MC

ACS omega 20190109 1

An indium-mediated isomerization of 1,4-dienols to 1,3-dienols is described. This procedure consists of the addition of pentadienylindium, in a protic solvent, to aldehydes giving the kinetic γ-allylation product in high yields. The subsequent conversion of this γ-allylation product to its thermodynamic 1,3-dienol α-isomer can be achieved by its exposure to indium triflate in the presence of a substoichiometric amount of aldehyde at room temperature. This transformation exhibited moderate to goo ...[more]

PMID: 31459359

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