Highly Enantioselective Benzoin Condensation Reactions Involving a Bifunctional Protic Pentafluorophenyl-Substituted Triazolium Precatalyst

Improved catalyst design by incorporating a hydrogen bond donating substituent to improve enantiocontrol together with an acidifying pentafluorophenyl substituent to enhance catalyst efficiency results in a triazolium ion precatalyst that promotes the asymmetric archetypal benzoin condensation with excellent efficiency and unprecedented enantioselectivity.