Copper(I)-Mediated Borofluorination of Alkynes

Area of Science:

• Organic Chemistry
• Organometallic Chemistry
• Fluorine Chemistry

Background:

• N-heterocyclic carbenes (NHCs) are versatile ligands in organometallic chemistry.
• Electrophilic fluorination is a key transformation for introducing fluorine into organic molecules.
• Developing selective methods for fluoroalkene synthesis remains an active area of research.

Purpose of the Study:

• To develop a novel synthetic route for fluoroalkenes.
• To achieve anti-Markovnikov fluorination of alkynes.
• To explore the utility of NHC-copper complexes in fluorination reactions.

Main Methods:

• Electrophilic fluorination of NHC copper(I) vinyls.
• In situ generation of (NHC)copper(I) boryl species.
• Reaction of alkynes with (NHC)copper(I) boryl and N-fluorobenzenesulfonimide (NFSI).
• Oxidation and Suzuki-Miyaura coupling of fluorinated intermediates.

Main Results:

• Fluoroalkene formation via electrophilic fluorination of NHC copper(I) vinyls.
• Synthesis of cis-(β-fluorovinyl)boronates from alkynes.
• Demonstration of anti-Markovnikov fluorination of terminal alkynes.
• Access to α-fluoroketones and tetrasubstituted monofluoroalkenes.

Conclusions:

• The developed method provides efficient access to valuable fluorinated organic compounds.
• This work expands the scope of NHC-copper catalysis in synthetic organic chemistry.
• The strategy offers a new pathway for anti-Markovnikov fluorination of alkynes.