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Updated: May 10, 2026
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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Catalytic ketyl-olefin cyclizations enabled by proton-coupled electron transfer
Kyle T Tarantino1, Peng Liu, Robert R Knowles
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Journal of the American Chemical Society
|June 26, 2013
Summary
Researchers developed a new catalytic method for ketyl-olefin coupling, utilizing concerted proton-coupled electron transfer for substrate activation. This mechanism, previously limited in organic synthesis, enables efficient ketyl formation and reaction prediction.
Area of Science:
- Organic Chemistry
- Catalysis
- Redox Chemistry
Background:
- Concerted proton-coupled electron transfer (CPET) is vital for biological redox catalysis but underexplored in organic synthesis.
- Substrate activation via CPET is a key challenge in developing novel synthetic methodologies.
Purpose of the Study:
- To develop a new catalytic protocol for ketyl-olefin coupling.
- To investigate and provide evidence for concerted proton-coupled electron transfer as the mechanism for ketyl formation in this reaction.
Main Methods:
- Development of a novel catalytic system for ketyl-olefin coupling.
- Spectroscopic and electrochemical analyses to support the proposed reaction mechanism.
- Thermodynamic modeling using oxidation potentials and pKa values to predict reaction outcomes.
Main Results:
- Successful implementation of a catalytic protocol for ketyl-olefin coupling.
- Evidence supporting concerted proton-coupled electron transfer as the key step in ketyl intermediate formation.
- Accurate prediction of reaction outcomes using a thermodynamic formalism for hydrogen atom donation.
Conclusions:
- Concerted proton-coupled electron transfer can be effectively applied to organic synthesis, specifically in ketyl-olefin coupling.
- The developed thermodynamic model provides a predictive tool for designing similar CPET-based catalytic systems.
- This work expands the synthetic utility of CPET beyond biological systems.
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