Palladium Catalyzed Radical Fluorination of Arylacetic Acid Equivalents via α-Carbonyl Radicals

A palladium catalyzed highly chemo- and site-selective radical benzylic fluorination of arylacetic acids with Selectfluor has been developed. The reaction gives an expedient access to fluorinated acetic acids with exceptional α-selectivity. The fluorination proceeds via a pyridine directed, SET-induced formation of α-carbonyl radicals followed by a fluorine atom transfer (FAT) process involving a PdI-intermediate. DFT studies corroborated the experimental results.