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Photocatalytic Synthesis of Polycyclic Indolones.

ABSTRACT: In this work, a photocatalytic strategy for a rapid and modular access to polycyclic indolones starting from readily available indoles is reported. This strategy relies on the use of redox-active esters in combination with an iridium-based photocatalyst under visible-light irradiation. The generation of alkyl radicals through decarboxylative single electron reductions enables intramolecular homolytic aromatic substitutions with a pending indole moiety to afford pyrrolo- and pyridoindolone derivatives under mild conditions. Furthermore, it was demonstrated that these radicals could also be engaged into cascades consisting of an intermolecular Giese-type addition followed by an intramolecular homolytic aromatic substitution to rapidly assemble valuable azepinoindolones.

SUBMITTER: Saget T

PROVIDER: S-EPMC7317559 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Photocatalytic Synthesis of Polycyclic Indolones.

Saget Tanguy T König Burkhard B

Chemistry (Weinheim an der Bergstrasse, Germany) 20200514 31

In this work, a photocatalytic strategy for a rapid and modular access to polycyclic indolones starting from readily available indoles is reported. This strategy relies on the use of redox-active esters in combination with an iridium-based photocatalyst under visible-light irradiation. The generation of alkyl radicals through decarboxylative single electron reductions enables intramolecular homolytic aromatic substitutions with a pending indole moiety to afford pyrrolo- and pyridoindolone deriva ...[more]

PMID: 32267567

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