Silver-Enabled General Radical Difluoromethylation Reaction with TMSCF2 H
Jun Yang1, Shengqing Zhu1, Fang Wang1
1State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology, Center for Advanced Low-Dimension Materials, Donghua University, Shanghai, 201620, China.
Angewandte Chemie (International Ed. in English)
|November 16, 2020
Summary
Researchers developed a new silver-catalyzed reaction to add the difluoromethyl group (CF2H) to alkenes. This efficient method provides a versatile route to valuable difluoromethylated compounds from readily available starting materials.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Difluoromethyl (CF2H) containing compounds are important in pharmaceuticals and agrochemicals.
- Existing methods for introducing the CF2H group can be limited in scope or require harsh conditions.
Purpose of the Study:
- To develop a novel, efficient, and versatile method for the difluoromethylation of alkenes.
- To establish a direct route to CF2H-alkenes using readily available starting materials.
Main Methods:
- Silver-mediated oxidative difluoromethylation reaction.
- Utilized styrenes and vinyl trifluoroborates as substrates.
- Employed trimethyl(difluoromethyl)silane (TMSCF2H) as the difluoromethyl source.
Main Results:
- Successfully achieved the direct difluoromethylation of styrenes and vinyl trifluoroborates.
- Demonstrated excellent functional-group compatibility of the developed method.
- Showcased the protocol's ability to serve as a platform for various radical difluoromethylation reactions.
Conclusions:
- The reported silver-catalyzed reaction provides a facile and direct method for synthesizing CF2H-alkenes.
- This protocol offers a valuable and complementary approach for constructing diverse carbon-difluoromethyl bonds.
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