Catalytic defluorinative ketyl-olefin coupling by halogen-atom transfer

Area of Science:

• Organic Chemistry
• Synthetic Chemistry

Background:

• Ketyl-olefin coupling is crucial for synthesizing complex molecules.
• Catalytic versions were limited until recent advances in photoredox and electrosynthesis.
• Single-electron transfer mechanisms have opened new avenues.

Purpose of the Study:

• To develop a new catalytic ketyl-olefin coupling reaction.
• To provide efficient access to gem-difluorohomoallylic alcohols.
• To explore a halogen-atom transfer mechanism for this transformation.

Main Methods:

• Utilizing a halogen-atom transfer mechanism.
• Employing Lewis acid activation.
• Leveraging radical addition and subsequent transformations.

Main Results:

• Achieved catalytic ketyl-olefin coupling via halogen-atom transfer.
• Synthesized various gem-difluorohomoallylic alcohols.
• Demonstrated broad substrate scope and mild reaction conditions.

Conclusions:

• The developed method offers an innovative route to valuable fluorinated compounds.
• The reaction proceeds through a radical-to-polar crossover pathway.
• This work expands the toolkit for catalytic ketyl-olefin coupling.