Enantioselective 1,4-addition of diarylphosphine oxides to α,β-unsaturated ketones catalyzed by oxazaborolidines

Abstract

Classical proline-derived oxazaborolidines as powerful and versatile organocatalysts (CBS, Corey–Bakshi–Shibata) have significant applications in asymmetric catalysis, especially in enantioselective reduction of prochiral ketones and various asymmetric cycloaddition reactions. Despite having been well-studied, their new applications are still very attractive and challenging. Hence, in this research, we disclose a new strategy for the asymmetric carbon–phosphorus bond forming reaction by using CBS catalysts via non-covalent interactions. Notably, various α,β-unsaturated ketones as substrates showed remarkable tolerance to various diarylphosphine oxides.