Asymmetric dehydration of β-hydroxy esters and application to the syntheses of flavane derivatives
作者:Eui Ta Choi、Min Hee Lee、Yongtae Kim、Yong Sun Park
DOI:10.1016/j.tet.2007.11.026
日期:2008.2
Catalytic asymmetric dehydration of β-aryl or alkyl substituted β-hydroxy esters via kinetic resolution has been investigated. A brief survey of 10 different chiral ligands is conducted to examine the effects of chiral ligand structure on selectivity of the dehydration. The kinetic resolution of a variety of rac-β-hydroxy tert-butyl esters in the presence of prolinol chiral ligand 2 and BrZnCH2CO2-t-Bu
已经研究了通过动力学拆分对β-芳基或烷基取代的β-羟基酯进行催化不对称脱水的方法。简要调查了10种不同的手性配体,以研究手性配体结构对脱水选择性的影响。在脯氨醇手性配体2和BrZnCH 2 CO 2 - t -Bu存在下,多种rac -β-羟基叔丁酯的动力学拆分可提供高度对映体富集的β-羟基酯14 – 21,选择性因子为11至66.此外,这种不对称合成方法在制备对映体富集的黄烷衍生物中的应用演示了25 – 29。