Enantioselective isothiourea-catalysed α-fluorination of C1-ammonium enolates generated from arylesters.

We herein report the chiral isothiourea-catalyzed α-fluorination of electron-deficient arylesters. This transformation proceeds via the in situ formation of chiral C1-ammonium enolates, which then undergo the α-fluorination with high levels of enantioselectivities, followed by addition of alcohols, such as MeOH, to give the final chiral α-F-esters.