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Enantioselective counter-anions in photoredox catalysis: the asymmetric cation radical Diels-Alder reaction.

ABSTRACT: Control of absolute stereochemistry in radical and ion radical transformations is a major challenge in synthetic chemistry. Herein, we report the design of a photoredox catalyst system comprised of an oxidizing pyrilium salt bearing a chiral N-triflyl phosphoramide anion. This class of chiral organic photoredox catalysts is able to catalyze the formation of cation radical-mediated Diels-Alder transformations in up to 75:25 e.r. in both intramolecular and intermolecular examples.

SUBMITTER: Morse PD

PROVIDER: S-EPMC6166882 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Enantioselective counter-anions in photoredox catalysis: the asymmetric cation radical Diels-Alder reaction.

Morse Peter D PD Nguyen Tien M TM Cruz Cole L CL Nicewicz David A DA

Tetrahedron 20180326 26

Control of absolute stereochemistry in radical and ion radical transformations is a major challenge in synthetic chemistry. Herein, we report the design of a photoredox catalyst system comprised of an oxidizing pyrilium salt bearing a chiral <i>N-</i>triflyl phosphoramide anion. This class of chiral organic photoredox catalysts is able to catalyze the formation of cation radical-mediated Diels-Alder transformations in up to 75:25 e.r. in both intramolecular and intermolecular examples. ...[more]

PMID: 30287974

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