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Metal-free photoredox-catalyzed direct α-oxygenation of N,N-dibenzylanilines to imides under visible light.

ABSTRACT: An efficient synthesis of imides using metal-free photoredox-catalyzed direct α-oxygenation of N,N'-disubstituted anilines in the presence of 9-mesityl-10-methylacridinium [Acr⁺-Mes]BF₄ as a photoredox catalyst and molecular oxygen as a green oxidant under visible light was developed. This photochemical approach offered operational simplicity, high atom economy with a low E-factor, and functional group tolerance under mild reaction conditions. Control and quenching experiments confirmed the occurrence of a radical pathway and superoxide radical anion α-oxygenation reactions, and also provided strong evidence for the reductive quenching of [Acr⁺-Mes]BF₄ based on a Stern-Volmer plot, which led to the proposed mechanism of this reaction.

SUBMITTER: Neerathilingam N

PROVIDER: S-EPMC8984950 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Metal-free photoredox-catalyzed direct α-oxygenation of N,N-dibenzylanilines to imides under visible light.

Neerathilingam Nalladhambi N Anandhan Ramasamy R

RSC advances 20220315 14

An efficient synthesis of imides using metal-free photoredox-catalyzed direct α-oxygenation of N,N'-disubstituted anilines in the presence of 9-mesityl-10-methylacridinium [Acr+-Mes]BF4 as a photoredox catalyst and molecular oxygen as a green oxidant under visible light was developed. This photochemical approach offered operational simplicity, high atom economy with a low E-factor, and functional group tolerance under mild reaction conditions. Control and quen ...[more]

PMID: 35424823

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