Speaker
Thomas Puleo
Speaker's Institution
Colorado State University
Date
6/6/22
Time
4:00pm
Location
Chemistry A101
Mixer Time
3:45pm
Mixer Location
Chemistry B101E
Additional Information

About the Talk:

The trifluoromethoxy (-OCF3) substituent has emerged as a prominent functional group in the development of new pharmaceuticals, agrochemicals, and functional materials. A widely utilized approach to form carbon-OCF3 bonds is nucleophilic substitution of electrophiles with trifluoromethoxide. Despite significant developments in this area, facile decomposition of trifluoromethoxide into difluorocarbonyl and fluoride has prevented the development and commercialization of shelf-stable trifluoromethoxide salts. Instead, reagents have been developed that release trifluoromethoxide in situ upon treatment with a nucleophile or a base. Beyond practical limitations such as reagent volatility and cost, the electrophile scope of this approach is limited to alkyl halides and few aromatic compounds. Meanwhile, fluoride substitution is a significant competing side reaction, limiting reaction yields and complicating purification. The overall goal of this proposal is to invent new trifluoromethoxide reagents that address the practical limitations of modern reagents and expand the scope of electrophile coupling partners in trifluoromethoxide substitution reactions. Success within this work could be translated to the development of reagents that generate other unstable anions for nucleophilic substitution reactions.