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Photoredox ketone catalysis for the direct C-H imidation and acyloxylation of arenes.

ABSTRACT: The photoexcited aryl ketone-catalyzed C-H imidation of arenes and heteroarenes is reported. Using 3,6-dimethoxy-9H-thioxanthen-9-one as a catalyst in combination with a bench-stable imidating reagent, C-N bond formation proceeds with high efficiency and a broad substrate scope. A key part of this method is that the thioxanthone catalyst acts as an excited-state reductant, thus establishing an oxidative quenching cycle for radical aromatic substitution. The synthetic potential of this photoexcited ketone catalysis is further demonstrated by application to the direct C-H acyloxylation of arenes.

SUBMITTER: Tripathi CB

PROVIDER: S-EPMC5620997 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Photoredox ketone catalysis for the direct C-H imidation and acyloxylation of arenes.

Tripathi Chandra Bhushan CB Ohtani Tsuyoshi T Corbett Michael T MT Corbett Michael T MT Ooi Takashi T

Chemical science 20170605 8

The photoexcited aryl ketone-catalyzed C-H imidation of arenes and heteroarenes is reported. Using 3,6-dimethoxy-9<i>H</i>-thioxanthen-9-one as a catalyst in combination with a bench-stable imidating reagent, C-N bond formation proceeds with high efficiency and a broad substrate scope. A key part of this method is that the thioxanthone catalyst acts as an excited-state reductant, thus establishing an oxidative quenching cycle for radical aromatic substitution. The synthetic potential of this pho ...[more]

PMID: 28989599

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