title: Pd-catalyzed arylation of silyl enol ethers of substituted alpha-fluoroketones.
abstract: Alpha-fluoro-alpha-aryl-ketones were synthesized by the Pd-catalyzed cross-coupling of aryl bromides with either alpha-fluoroketones or their corresponding silyl enol ethers. The direct arylation with an alpha-fluoroketone requires a strong base, such as potassium tert-butoxide, and under these conditions the presence of a base-sensitive functional group is not compatible. However, good functional tolerance was achieved when the anionic coupling moieties were generated from the silyl enol ethers obtained by reacting alpha-fluoroketones with tetrabutylammonium (tripheny1silyl)difluorosilicate (TBAT) as the fluoride source under nearly neutral conditions. The aryl halides with a carbmethoxy, nitro, cyano or carbonyl group were used. The reaction with nonfluorinated silyl enol ether 1h gave a cross-coupling product in low yield.
authors.affiliation: Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Guo
authors.forename: Brendan
authors.initials: B
authors.lastname: Twamley
authors.forename: Jean'ne M
authors.initials: JM
authors.lastname: Shreeve