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Combined Photoredox and Carbene Catalysis for the Synthesis of γ-Aryloxy Ketones.

ABSTRACT: N-heterocyclic carbenes (NHCs) have emerged as catalysts for the construction of C-C bonds in the synthesis of substituted ketones under single-electron processes. Despite these recent reports, there still remains a need to increase the utility and practicality of these reactions by exploring new radical coupling partners. Herein, we report the synthesis of γ-aryloxyketones via combined NHC/photoredox catalysis. In this reaction, an α-aryloxymethyl radical is generated via oxidation of an aryloxymethyl potassium trifluoroborate salt, which is then added into styrene derivatives to provide a stabilized benzylic radical. Subsequent radical-radical coupling reaction with an azolium radical affords the γ-aryloxy ketone products.

SUBMITTER: Wang P

PROVIDER: S-EPMC9012476 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Combined Photoredox and Carbene Catalysis for the Synthesis of γ-Aryloxy Ketones.

Wang Pengzhi P Fitzpatrick Keegan P KP Scheidt Karl A KA

Advanced synthesis & catalysis 20211201 3

<i>N</i>-heterocyclic carbenes (NHCs) have emerged as catalysts for the construction of C-C bonds in the synthesis of substituted ketones under single-electron processes. Despite these recent reports, there still remains a need to increase the utility and practicality of these reactions by exploring new radical coupling partners. Herein, we report the synthesis of γ-aryloxyketones via combined NHC/photoredox catalysis. In this reaction, an α-aryloxymethyl radical is generated via oxidation of an ...[more]

PMID: 35431717

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