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Radical/Polar Annulation Reactions (RPARs) Enable the Modular Construction of Cyclopropanes.

ABSTRACT: An annulation process for the construction of 1,1-disubstituted cyclopropanes via a radical/polar crossover process is described. The cyclopropanation proceeds by the addition of a photocatalytically generated radical to a homoallylic tosylate. Reduction of the intermediate radical alkylation adduct (via single electron transfer) furnishes an anion that undergoes an intramolecular substitution. The process displays excellent functional group tolerance, characteristic of proceeding through odd-electron intermediates, and occurs under mild conditions with visible light irradiation.

SUBMITTER: Milligan JA

PROVIDER: S-EPMC6218941 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Radical/Polar Annulation Reactions (RPARs) Enable the Modular Construction of Cyclopropanes.

Milligan John A JA Phelan James P JP Polites Viktor C VC Kelly Christopher B CB Molander Gary A GA

Organic letters 20181015 21

An annulation process for the construction of 1,1-disubstituted cyclopropanes via a radical/polar crossover process is described. The cyclopropanation proceeds by the addition of a photocatalytically generated radical to a homoallylic tosylate. Reduction of the intermediate radical alkylation adduct (via single electron transfer) furnishes an anion that undergoes an intramolecular substitution. The process displays excellent functional group tolerance, characteristic of proceeding through odd-el ...[more]

PMID: 30350660

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