Catalytic Asymmetric Hydrophosphinylation of α,β-Unsaturated <i>N</i>-Acylpyrroles: Application of Dialkyl Phosphine Oxides in Enantioselective Synthesis of Chiral Phosphine Oxides or Phosphines

Abstract

Dialkyl phosphine oxides were introduced in catalytic asymmetric transformations for the first time. An unprecedented phospha-Michael reaction of dialkyl phosphine oxide with alpha,beta-unsaturated N-acylpyrroles was disclosed. Excellent enantioselectivities (94-->99% ee) and chemical yields (up to 99%) were achieved with a broad substrate scope of the N-acylpyrroles. Importantly, pyridine was found to be critical to achieve good results for the present reaction.