AgBF4-catalyzed insertion of unactivated alkynes into C-F bonds of acyl fluorides
Tomoya Emmei1, Mamoru Tobisu1,2
1Department of Applied Chemistry, Graduate School of Engineering, The University of Osaka Osaka 565-0871 Japan tobisu@chem.eng.osaka-u.ac.jp.
Abstract:
We report an AgBF4-catalyzed intermolecular C-F insertion of unactivated alkynes into acyl fluorides, providing a general route to monofluoroalkenes. This transformation enables both C-F bond cleavage and reformation without activated coupling partners, driven by cooperative Ag+/BF4 - catalysis, where BF4 - functions as a fluoride shuttle. The reaction exhibits broad substrate scope, accommodating aromatic and aliphatic acyl fluorides with high Z-selectivity. Given that monofluoroalkenes are valuable amide bioisosteres, this method enables direct access to bio-relevant motifs from carboxylic acid derivatives and supports late-stage monofluoroalkene installation in complex molecules.
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