A practical enantioselective synthesis of .alpha.,.alpha.-diaryl-2-pyrrolidinemethanol. Preparation and chemistry of the corresponding oxazaborolidines
摘要:
A practical two-step enantioselective synthesis of alpha,alpha-diaryl-2-pyrrolidinemethanols (1) from proline, based on the addition of aryl Grignard reagents to proline-N-carboxanhydride (3), is reported. An investigation into the chemistry of the corresponding B-alkyl- and B-aryloxazaborolidines (2) led to the development of a reliable procedure for their preparation.