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Ring-Opening Fluorination of Isoxazoles
Masaaki Komatsuda1, Hugo Ohki1, Hiroki Kondo1
1Department of Applied Chemistry, Waseda University, 513 Wasedatsurumakicho, Shinjuku, Tokyo 162-0041, Japan.
Organic Letters
|April 26, 2022
Summary
A novel ring-opening fluorination of isoxazoles was developed using Selectfluor. This method efficiently produces tertiary fluorinated carbonyl compounds under mild conditions, offering a versatile route to diverse fluorinated molecules.
Area of Science:
- Organic Chemistry
- Fluorination Chemistry
- Heterocyclic Chemistry
Background:
- Isoxazoles are important heterocyclic compounds.
- Fluorinated organic compounds possess unique properties and find applications in pharmaceuticals and materials science.
- Developing efficient methods for introducing fluorine into organic molecules is crucial.
Purpose of the Study:
- To develop a novel ring-opening fluorination reaction for isoxazoles.
- To synthesize tertiary fluorinated carbonyl compounds.
- To explore the synthetic utility of the resulting fluorinated intermediates.
Main Methods:
- Treatment of isoxazoles with an electrophilic fluorinating agent, Selectfluor.
- Fluorination followed by deprotonation.
- Subsequent transformations of α-fluorocyanoketones.
Main Results:
- Successful development of a ring-opening fluorination of isoxazoles.
- Efficient synthesis of tertiary fluorinated carbonyl compounds.
- Demonstration of diverse transformations of α-fluorocyanoketones, yielding various fluorinated compounds.
- The reaction proceeds under mild conditions with good functional group tolerance and a simple procedure.
Conclusions:
- A new and efficient method for the synthesis of fluorinated carbonyl compounds from isoxazoles has been established.
- The developed methodology offers a valuable tool for accessing diverse fluorinated molecules.
- The reaction's mild conditions and broad functional group tolerance make it attractive for synthetic applications.
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