New electrophilic difluoromethylating reagent
G K Surya Prakash1, Csaba Weber, Sujith Chacko
1Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, CA 90089-1661, USA. gprakash@usc.edu
Organic Letters
|April 21, 2007
Summary
A novel S-(difluoromethyl)diarylsulfonium tetrafluoroborate reagent enables electrophilic difluoromethylation. This new method efficiently introduces the difluoromethyl group into various nucleophiles like sulfonic acids and amines.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Difluoromethylation is crucial for modifying molecular properties.
- Development of efficient electrophilic difluoromethylating reagents is ongoing.
Purpose of the Study:
- To develop a new electrophilic difluoromethylating reagent.
- To evaluate the reagent's scope and limitations.
Main Methods:
- Synthesis of S-(difluoromethyl)diarylsulfonium tetrafluoroborate.
- Testing the reagent with various nucleophiles (sulfonic acids, amines, imidazoles, phosphines, phenols, carbon nucleophiles).
Main Results:
- The reagent successfully difluoromethylated sulfonic acids, tertiary amines, imidazole derivatives, and phosphines.
- The reagent was ineffective for phenols, carbon nucleophiles, and primary/secondary amines.
Conclusions:
- S-(difluoromethyl)diarylsulfonium tetrafluoroborate is a useful reagent for specific electrophilic difluoromethylations.
- The reagent's reactivity is dependent on the nucleophile's electronic properties.
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