Asymmetric [2,3]-Wittig Rearrangement Involving a Chiral Ester Enolate Terminus. A Chiral Synthesis of<i>erythro</i>-α-Hydroxy-β-alkyl Carboxylic Acid Derivatives
作者:Osamu Takahashi、Koichi Mikami、Takeshi Nakai
DOI:10.1246/cl.1987.69
日期:1987.1.5
The title rearrangement of the (E-2-alkenyloxy)acetic esters derived from (−)-8-phenylmenthol has been shown to afford the corresponding 3-alkyl-2-hydroxy-4-pentenoic ester with an extremely high level of diastereoface selection (95–97% de) along with a high erythro selectivity (90–93%).
The title rearrangement of the chiral (E-crotyloxy)acetamides derived from (S)-prolinol has been shown to provide a modest level of asymmetricinduction (52–60%) along with a high erythro-selectivity (95–98%). The influence of the metal centers (Li, K, and Zr) and the ligating substituents on the prolinol part has been discussed.