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Catalytic β C-H amination via an imidate radical relay
Leah M Stateman1, Ethan A Wappes1, Kohki M Nakafuku1
1The Ohio State University , Department of Chemistry and Biochemistry , Columbus , OH 43210 , USA .
Chemical Science
|April 19, 2019
Summary
A new catalytic method uses imidate radicals for C-H functionalization via an iodine-catalyzed radical relay. This efficient approach broadens functional group tolerance for β C-H amination of alcohols.
Area of Science:
- Organic Chemistry
- Catalysis
- Radical Chemistry
Background:
- C-H functionalization is crucial for synthesizing complex organic molecules.
- Radical relay mechanisms offer unique synthetic pathways.
- Previous methods for imidate radical functionalization were stoichiometric.
Purpose of the Study:
- To develop the first catalytic strategy for imidate radical-mediated C-H functionalization.
- To enable β C-H amination of alcohols using a catalytic radical relay.
- To improve efficiency and functional group tolerance compared to prior methods.
Main Methods:
- Iodine-catalyzed reaction.
- Imidate-mediated radical relay mechanism.
- Investigation of chemo-, regio-, and stereo-selectivity.
- Mechanistic studies including H-atom transfer analysis.
Main Results:
- Developed the first catalytic strategy for imidate radical C-H functionalization.
- Achieved efficient β C-H amination of alcohols.
- Demonstrated broader functional group tolerance with lower oxidant concentration.
- Provided mechanistic insights into the radical relay and H-atom transfer.
Conclusions:
- The developed catalytic system is a significant advancement in imidate radical chemistry.
- This method offers a more efficient and versatile approach to C-H functionalization.
- The findings open new avenues for synthesizing functionalized organic compounds.
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