Direct Regioselective para-Fluorination via I(I)/I(III) Catalysis
Christoph Roblick1, Julian D Bendix1, Timothy A Hilton1
1Institute for Organic Chemistry, University of Münster, Münster, Germany.
Angewandte Chemie (International Ed. in English)
|July 9, 2026
Summary
Researchers developed a direct para-selective fluorination method using iodine catalysis. This strategy efficiently introduces fluorine into drug molecules, aiding the exploration of organo-fluorine chemical space.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Catalysis
Background:
- Fluorine scanning is crucial for enhancing drug properties.
- The para-fluorophenyl motif is a key structure in many drugs.
- Efficient synthesis of para-fluorinated compounds is needed.
Purpose of the Study:
- To develop a direct, para-selective fluorination method.
- To enable synthesis without pre-functionalization of substrates.
- To explore organo-fluorine chemical space for drug discovery.
Main Methods:
- Utilized I(I)/I(III) catalysis for direct fluorination.
- Employed a strategy leveraging the Leonard link for spirocyclization and para-selective activation.
- Applied the method to phenylpropanoates, phenylpropanamides, amino acids, and dipeptides.
Main Results:
- Achieved direct, para-selective fluorination.
- Demonstrated high yields (up to 94%) for various substrates.
- X-ray crystallography revealed specific intermolecular interactions involving the C-F bond.
Conclusions:
- Developed an organocatalytic platform for direct para-fluorination.
- This method facilitates the synthesis of valuable para-fluorinated drug intermediates.
- The approach expands the possibilities for exploring organo-fluorine chemistry in drug design.
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