Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication

Huang, He; Strater, Zack M.; Rauch, Michael; Shee, James; Sisto, Thomas J.; Nuckolls, Colin; Lambert, Tristan H.

doi:10.1002/ange.201906381

Title: Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication

Abstract

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.

Authors:

Huang, He ^[1]; Strater, Zack M. ^[2]; Rauch, Michael ^[2]; Shee, James ^[2]; Sisto, Thomas J. ^[2]; Nuckolls, Colin ^[2];

^[3]

Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA
Department of Chemistry Columbia University New York NY 10027 USA
Department of Chemistry and Chemical Biology Cornell University Ithaca NY 14853 USA, Department of Chemistry Columbia University New York NY 10027 USA

Publication Date:: Fri Aug 02 00:00:00 EDT 2019

Sponsoring Org.:: USDOE

OSTI Identifier:: 1546094

Resource Type:: Publisher's Accepted Manuscript

Journal Name:: Angewandte Chemie

Additional Journal Information:: Journal Name: Angewandte Chemie Journal Volume: 131 Journal Issue: 38; Journal ID: ISSN 0044-8249

Publisher:: Wiley Blackwell (John Wiley & Sons)

Country of Publication:: Germany

Language:: English

Citation Formats


                    Huang, He, Strater, Zack M., Rauch, Michael, Shee, James, Sisto, Thomas J., Nuckolls, Colin, and Lambert, Tristan H. Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication.  Germany: N. p., 2019. 
Web.  doi:10.1002/ange.201906381.

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                    Huang, He, Strater, Zack M., Rauch, Michael, Shee, James, Sisto, Thomas J., Nuckolls, Colin, & Lambert, Tristan H. Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication.  Germany.  https://doi.org/10.1002/ange.201906381

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                    Huang, He, Strater, Zack M., Rauch, Michael, Shee, James, Sisto, Thomas J., Nuckolls, Colin, and Lambert, Tristan H. Fri .  
"Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication".  Germany.  https://doi.org/10.1002/ange.201906381.

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@article{osti_1546094,

  title        = {Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication},

  author       = {Huang, He and Strater, Zack M. and Rauch, Michael and Shee, James and Sisto, Thomas J. and Nuckolls, Colin and Lambert, Tristan H.},

  abstractNote = {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.},

  doi          = {10.1002/ange.201906381},

  journal      = {Angewandte Chemie},

  number       = 38,

  volume       = 131,

  place        = {Germany},

  year         = {Fri Aug 02 00:00:00 EDT 2019},

  month        = {Fri Aug 02 00:00:00 EDT 2019}

}

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Title: Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication

Abstract

Citation Formats

Solar Synthesis: Prospects in Visible Light Photocatalysis journal, February 2014

Phenothiazine Radical Cation Excited States as Super-oxidants for Energy-Demanding Reactions journal, March 2018

Organic Photoredox Catalysis journal, June 2016

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Tris (dimethylamino)-cyclopropenium radical dication journal, January 1971

Direct Oxygenation of Benzene to Phenol Using Quinolinium Ions as Homogeneous Photocatalysts journal, August 2011

Phototochemistry of cation radicals in solution; photoinduced electron-transfer reactions between alcholos and the N,N,N′,N′,-tetraphenyl-p-phenylenediamine cation radical journal, January 1982

Merging Photochemistry with Electrochemistry: Functional‐Group Tolerant Electrochemical Amination of C(sp 3 )−H Bonds journal, February 2019

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Site-selective arene C-H amination via photoredox catalysis journal, September 2015

Direct Oxygenation of Benzene to Phenol Using Quinolinium Ions as Homogeneous Photocatalysts journal, August 2011

Photoelectrochemical C−H Alkylation of Heteroarenes with Organotrifluoroborates journal, January 2019

Photo-induced oxidant-free oxidative C–H/N–H cross-coupling between arenes and azoles journal, February 2017

Electrochemistry of heterosubstituted cyclopropenyl cations journal, February 1976

Photoredox Catalysis in Organic Chemistry journal, June 2016

Visible light photoredox catalysis: applications in organic synthesis journal, January 2011

Aminocyclopropenium Ions: Synthesis, Properties, and Applications journal, August 2013

Solar Synthesis: Prospects in Visible Light Photocatalysis
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Phenothiazine Radical Cation Excited States as Super-oxidants for Energy-Demanding Reactions
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Organic Photoredox Catalysis
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Accurate Oxidation Potentials of Benzene and Biphenyl Derivatives via Electron-Transfer Equilibria and Transient Kinetics
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Photoelectrochemical C−H Alkylation of Heteroarenes with Organotrifluoroborates
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Catalysis of Radical Reactions: A Radical Chemistry Perspective
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Direct Oxygenation of Benzene to Phenol Using Quinolinium Ions as Homogeneous Photocatalysts
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Phototochemistry of cation radicals in solution; photoinduced electron-transfer reactions between alcholos and the N,N,N′,N′,-tetraphenyl-p-phenylenediamine cation radical
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Merging Photochemistry with Electrochemistry: Functional‐Group Tolerant Electrochemical Amination of C(sp ³ )−H Bonds
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Visible-Light-Induced Oxygenation of Benzene by the Triplet Excited State of 2,3-Dichloro-5,6-dicyano- p -benzoquinone
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