Asymmetric Fluorination of Enamides: Access to α-Fluoroimines Using an Anionic Chiral Phase-Transfer Catalyst

The use of a BINOL-derived phosphate as a chiral anionic phase-transfer catalyst in a nonpolar solvent allows the enantioselective fluorination of enamides using Selectfluor as the fluorinating reagent. We demonstrate that a wide range of stable and synthetically versatile α-(fluoro)benzoylimines can be readily accessed with high enantioselectivity. These compounds have the potential to be readily elaborated into a range of highly stereodefined β-fluoroamines, compounds that constitute highly valuable building blocks of particular importance in the synthesis of pharmaceuticals.