The synthesis of α,α-difluoroacetamides via electrophilic fluorination in the mixed-solvent of water and PEG-400

Under mild conditions, a series of α,α-difluoro-β-ketoamides were synthesized with Selectfluor® as the F+ source in the presence of K2CO3 in the mixed-solvent of water and PEG-400 ( V H 2 O : V PEG-400 = 3 : 1 ) , without additional phase-transfer catalyst. By using this approach, most cases examined in this study proceeded in nearly quantitative conversions regardless of the electronic nature of the substituent pattern.