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Redox-Neutral Photocatalytic Cyclopropanation via Radical/Polar Crossover.

ABSTRACT: A benchtop stable, bifunctional reagent for the redox-neutral cyclopropanation of olefins has been developed. Triethylammonium bis(catecholato)iodomethylsilicate can be readily prepared on multigram scale. Using this reagent in combination with an organic photocatalyst and visible light, cyclopropanation of an array of olefins, including trifluoromethyl- and pinacolatoboryl-substituted alkenes, can be accomplished in a matter of hours. The reaction is highly tolerant of traditionally reactive functional groups (carboxylic acids, basic heterocycles, alkyl halides, etc.) and permits the chemoselective cyclopropanation of polyolefinated compounds. Mechanistic interrogation revealed that the reaction proceeds via a rapid anionic 3- exo- tet ring closure, a pathway consistent with experimental and computational data.

SUBMITTER: Phelan JP

PROVIDER: S-EPMC6540794 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Redox-Neutral Photocatalytic Cyclopropanation via Radical/Polar Crossover.

Phelan James P JP Lang Simon B SB Compton Jordan S JS Kelly Christopher B CB Dykstra Ryan R Gutierrez Osvaldo O Molander Gary A GA

Journal of the American Chemical Society 20180619 25

A benchtop stable, bifunctional reagent for the redox-neutral cyclopropanation of olefins has been developed. Triethylammonium bis(catecholato)iodomethylsilicate can be readily prepared on multigram scale. Using this reagent in combination with an organic photocatalyst and visible light, cyclopropanation of an array of olefins, including trifluoromethyl- and pinacolatoboryl-substituted alkenes, can be accomplished in a matter of hours. The reaction is highly tolerant of traditionally reactive fu ...[more]

PMID: 29916711

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