Asymmetric Hydrogenation of α,β-Unsaturated Carboxylic Esters with Chiral Iridium N,P Ligand Complexes
作者:David H. Woodmansee、Marc-André Müller、Lars Tröndlin、Esther Hörmann、Andreas Pfaltz
DOI:10.1002/chem.201202397
日期:2012.10.22
Enantioselective conjugate reduction of a wide range of α,β‐unsaturated carboxylic esters was achieved using chiral Ir N,P complexes as hydrogenation catalysts. Depending on the substitution pattern of the substrate, different ligands perform best. α,β‐Unsaturated carboxylic esters substituted at the α position are less problematic substrates than originally anticipated and in some cases α‐substituted
使用手性Ir N,P配合物作为氢化催化剂,可以实现多种α,β-不饱和羧酸酯的对映选择性共轭还原。根据底物的取代方式,不同的配体表现最佳。在α位置被取代的α,β-不饱和羧酸酯的底物问题比最初预期的要少,并且在某些情况下,α-取代的底物实际上以比其β-取代的类似物更高的对映选择性进行反应。以高对映体纯度获得了在α或β位置具有立体异构中心的所得饱和酯。