Asymmetric Michael addition of nitroalkanes to prochiral acceptors catalyzed by proline rubidium salts
作者:Masahiko Yamaguchi、Yoshihiro Igarashi、Ravinder S Reddy、Tai Shiraishi、Masahiro Hirama
DOI:10.1016/s0040-4020(97)00379-7
日期:1997.8
Proline rubidium salts catalyze the asymmetric Michael addition of nitroalkanes to prochiral acceptors. When (2S)-L-prolines were used, acyclic (E)-enones gave (S)-adducts and cyclic (Z)-enones gave (R)-adducts predominantly. Enantiomeric excesses exceeding 80% were attained in some reactions of secondary nitroalkanes. Primary nitroalkanes gave mixtures of diastereomers which possess the same configuration