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09:58
Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
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Visible-light mediated directed perfluoroalkylation of hydrazones
Heng Ji1, Hui-Qiong Ni, Peng Zhi
1School of Chemical Engineering, Anhui University of Science and Technology, Huainan, P. R. China.
Organic & Biomolecular Chemistry
|July 6, 2017
Summary
Visible light photoredox reactions enable efficient perfluoroalkylation of hydrazones. This novel method expands substrate scope, including previously unreactive compounds, for synthesizing valuable fluorinated molecules.
Area of Science:
- Organic Chemistry
- Fluorine Chemistry
- Photochemistry
Background:
- Perfluoroalkylation introduces unique properties to organic molecules.
- Previous methods for hydrazone perfluoroalkylation had limited substrate scope and efficiency.
Purpose of the Study:
- To develop a novel, efficient, and versatile method for perfluoroalkylation of N-alkylhydrazones.
- To expand the scope of hydrazone perfluoroalkylation to include previously unreactive substrates.
Main Methods:
- Visible light mediated photoredox catalysis.
- Reaction of N-alkylhydrazones with perfluoroalkyl iodides (RfI).
- Utilized Stern-Volmer quenching and spin-trapping experiments to elucidate the reaction mechanism.
Main Results:
- Achieved efficient perfluoroalkylation of aromatic and aliphatic aldehyde hydrazones.
- Successfully perfluoroalkylated N-monosubstituted hydrazones, which were previously unreactive.
- Demonstrated tolerance for a wide range of functional groups on the aromatic ring.
- Utilized perfluoroalkyl iodides with up to eight carbon atoms.
Conclusions:
- Visible light photoredox catalysis offers a convenient and efficient route to perfluoroalkylated hydrazones.
- The developed protocol significantly broadens the applicability of hydrazone perfluoroalkylation.
- The reaction proceeds via a free radical mechanism involving radical addition to the azomethine atom.
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