LiBF4-Promoted Aromatic Fluorodetriazenation under Mild Conditions
Hongjin Zhang1,2, Jianbo Wu3,2, Xingxian Zhang3
1Academy of Medical Engineering and Translational Medicine (AMT), Tianjin University, Tianjin 300072, P.R. China.
The Journal of Organic Chemistry
|August 18, 2023
Summary
A new, mild fluorination method uses lithium tetrafluoroborate to convert triazenes into aryl fluorides efficiently. This process is fast, tolerates various functional groups, and offers good yields of valuable fluorinated compounds.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Fluorination Chemistry
Background:
- Aryl fluorides are important motifs in pharmaceuticals and agrochemicals.
- Developing efficient and mild fluorination methods remains a key challenge in organic synthesis.
Purpose of the Study:
- To develop a novel, mild, and efficient method for aromatic fluorodetriazenation.
- To synthesize aryl fluorides from readily available 3,3-dimethyl-1-aryltriazenes.
Main Methods:
- Utilized lithium tetrafluoroborate (LiBF4) as a promoter for the fluorodetriazenation reaction.
- Employed 3,3-dimethyl-1-aryltriazenes as substrates.
- Conducted reactions under mild conditions, avoiding protic or strong Lewis acids.
Main Results:
- Achieved efficient fluorination of aromatic triazenes.
- The reaction completed within 2 hours under mild conditions.
- Demonstrated tolerance to a wide range of functional groups.
- Obtained aryl fluoride products in moderate to excellent yields.
Conclusions:
- Developed a novel and efficient LiBF4-promoted aromatic fluorodetriazenation method.
- The method is mild, fast, and versatile, suitable for synthesizing diverse aryl fluorides.
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