Palladium-Catalyzed α-Arylation of α,α-Difluoro-β-Carbonyl Trifluoromethyl gem-Diols

Base-mediated elimination of trifluoroacetic acid from this substrate enabled the in situ generation of highly nucleophilic difluoroenolate anions. The resulting active intermediates efficiently underwent intermolecular α-arylation with aryl bromides under palladium catalysis, affording a series of α,α-difluoroarylketones.

The experimental results confirmed that the α-arylation reaction proceeded smoothly using the Pd(OAc)2/BINAP catalytic ligand system with Cs2CO3 as the base additive, providing structurally diverse α,α-difluoro-α-aryl ketone derivatives in moderate isolated yields. Substrate scope investigations demonstrated that this synthetic protocol tolerates aryl bromides with various electronic properties and steric hindrance.