Enantioselective Organocatalytic α-Fluorination of Cyclic Ketones

The first highly enantioselective alpha-fluorination of ketones using organocatalysis has been accomplished. The long-standing problem of enantioselective ketone alpha-fluorination via enamine activation has been overcome via high-throughput evaluation of a new library of amine catalysts. The optimal system, a primary amine functionalized Cinchona alkaloid, allows the direct and asymmetric a-fluorination of a variety of carbo- and heterocyclic substrates. Furthermore, this protocol also provides diastereo-, regio-, and chemoselective catalyst control in fluorinations involving complex carbonyl systems.