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Constructing the OCF2O moiety using BrF3
1School of Chemistry, Tel-Aviv University, Tel-Aviv 69978, Israel.
The Journal of Organic Chemistry
|August 13, 2008
Summary
A new method prepares difluoromethylenedioxy compounds from alcohols using thiophosgene and bromine trifluoride. This efficient fluorination occurs rapidly under mild conditions, yielding moderate to high amounts of the desired derivatives.
Area of Science:
- Organic Chemistry
- Fluorine Chemistry
Background:
- Difluoromethylenedioxy groups are important structural motifs in medicinal chemistry and materials science.
- Existing synthetic routes to these compounds can be limited in scope or require harsh conditions.
Purpose of the Study:
- To develop a general and efficient method for synthesizing aromatic and aliphatic difluoromethylenedioxy derivatives.
- To explore the use of bromine trifluoride (BrF3) in the preparation of these compounds.
Main Methods:
- Reaction of alcohols with thiophosgene to form thiocarbonates.
- Subsequent fluorination of thiocarbonates using bromine trifluoride (BrF3).
Main Results:
- The method is applicable to a wide range of alcohols, including aromatic, aliphatic, cyclic, linear, symmetric, and asymmetric substrates.
- Fluorination with BrF3 is rapid (seconds) and proceeds with moderate to high yields.
- The reaction conditions are mild, making the process suitable for sensitive substrates.
Conclusions:
- A versatile and efficient synthetic strategy for difluoromethylenedioxy derivatives has been established.
- The use of BrF3 offers a rapid and effective fluorination step under mild conditions.
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