Sugar-based phosphite and phosphoroamidite ligands for the Cu-catalyzed asymmetric 1,4-addition to enones
作者:Eva Raluy、Oscar Pàmies、Montserrat Diéguez、Stephane Rosset、Alexander Alexakis
DOI:10.1016/j.tetasy.2009.09.002
日期:2009.9
A modular sugar-based phosphoroamidite L1–L5a–g and phosphite L6–L9a–g ligand library was tested in the asymmetric Cu-catalyzed 1,4-conjugate addition reactions of β-substituted (cyclic and linear) and β,β′-disubstituted (cyclic) enones. The selectivity depended strongly on the configuration of carbon atom C-3, the size of the sugar backbone ring, the flexibility of the ligand backbone, the substituents
在不对称的铜催化的β-取代的(环状和线性)与β,β'-的1,4-共轭加成反应中,测试了模块化糖基亚磷酰胺L1 - L5a - g和亚磷酸酯L6 - L9a - g配体库二取代(环状)烯酮。选择性很大程度上取决于碳原子C-3的构型,糖主链的大小,配体主链的柔韧性,联芳基亚磷酰胺部分a – g中的取代基和构型,是连接到配体主链和底物结构上的官能团的类型。因此,通过仔细选择配体参数,对环状底物的对映选择性高达60%,对于线性底物的对映选择性高达72%。