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 carboxylicesters 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 carboxylicesters substituted at the α position are less problematic substrates than originally anticipated and in some cases α‐substituted
asymmetric hydrogenation has emerged as a highly efficient method for the synthesis of enantiomerically pure compounds. This account summarizes our recent efforts in this field. We have developed a new type of P,O-ligand that was successfully applied to the asymmetric hydrogenation of alpha,beta-unsaturated carbonyl compounds. Furthermore we have demonstrated the potential of known iridium catalysts in the