Electrochemical Nickel-Catalyzed Selective Defluorination for the Synthesis of α-Fluoroarylacetic Acid Derivatives

We report an electrochemical nickel-catalyzed reductive cross-coupling for the synthesis of α-aryl monofluorinated carboxylic acid derivatives from aryl iodides and 2-chloro-2,2-difluoroacetates. The reaction is conducted in an undivided cell, affording the corresponding phenanthrenyl derivative in a high yield (up to 80%). This protocol exhibits broad functional group tolerance and is applicable to a wide range of structurally complex molecules, as demonstrated by more than 50 examples. Key advantages of this strategy include: the use of electrons as a traceless reductant, which avoids the need for exogenous stoichiometric reagents; effective suppression of overdefluorination─a common challenge in photoredox Ni-catalysis─through FeCl₃ mediation; and the elimination of expensive photocatalysts, thereby offering a practical and scalable alternative. Mechanistic studies indicate the participation of radical intermediates and a Lewis-acid-mediated catalytic cycle.