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Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication.

ABSTRACT: Visible-light photocatalysis and electrocatalysis are two powerful strategies for the promotion of chemical reactions. Here, these two modalities are combined in an electrophotocatalytic oxidation platform. This chemistry employs a trisaminocyclopropenium (TAC) ion catalyst, which is electrochemically oxidized to form a cyclopropenium radical dication intermediate. The radical dication undergoes photoexcitation with visible light to produce an excited-state species with oxidizing power (3.33?V vs. SCE) sufficient to oxidize benzene and halogenated benzenes via single-electron transfer (SET), resulting in C-H/N-H coupling with azoles. A rationale for the strongly oxidizing behavior of the photoexcited species is provided, while the stability of the catalyst is rationalized by a particular conformation of the cis-2,6-dimethylpiperidine moieties.

SUBMITTER: Huang H

PROVIDER: S-EPMC7168342 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication.

Huang He H Strater Zack M ZM Rauch Michael M Shee James J Sisto Thomas J TJ Nuckolls Colin C Lambert Tristan H TH

Angewandte Chemie (International ed. in English) 20190802 38

Visible-light photocatalysis and electrocatalysis are two powerful strategies for the promotion of chemical reactions. Here, these two modalities are combined in an electrophotocatalytic oxidation platform. This chemistry employs a trisaminocyclopropenium (TAC) ion catalyst, which is electrochemically oxidized to form a cyclopropenium radical dication intermediate. The radical dication undergoes photoexcitation with visible light to produce an excited-state species with oxidizing power (3.33 V v ...[more]

PMID: 31306561

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