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Radical-Polar Crossover Annulation: A Platform for Accessing Polycyclic Cyclopropanes.

ABSTRACT: Photoredox-mediated radical/polar crossover (RPC) processes provide unique solutions to challenging annulations. Herein, we describe an approach to the cyclopropanation of olefins that are embedded within bicyclic scaffolds. Whereas these systems are notoriously recalcitrant toward classical cyclopropanation approaches, RPC cyclopropanation can be executed with ease, leading to polycarbocyclic and polyheterocyclic cyclopropanes. The cyclopropanation proceeds through a photoredox-enabled Giese-type radical addition followed by an intramolecular anionic substitution reaction on a neopentyl leaving group.

SUBMITTER: Milligan JA

PROVIDER: S-EPMC8172062 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Radical-Polar Crossover Annulation: A Platform for Accessing Polycyclic Cyclopropanes.

Milligan John A JA Burns Kevin L KL Le Anthony V AV Polites Viktor C VC Wang Zheng-Jun ZJ Molander Gary A GA Kelly Christopher B CB

Advanced synthesis & catalysis 20191108 1

Photoredox-mediated radical/polar crossover (RPC) processes provide unique solutions to challenging annulations. Herein, we describe an approach to the cyclopropanation of olefins that are embedded within bicyclic scaffolds. Whereas these systems are notoriously recalcitrant toward classical cyclopropanation approaches, RPC cyclopropanation can be executed with ease, leading to polycarbocyclic and polyheterocyclic cyclopropanes. The cyclopropanation proceeds through a photoredox-enabled Giese-ty ...[more]

PMID: 34084099

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