Axially chiral P-N ligands for the copper catalyzed β-borylation of α,β-unsaturated esters
作者:William J. Fleming、Helge Müller-Bunz、Vanesa Lillo、Elena Fernández、Patrick J. Guiry
DOI:10.1039/b900741e
日期:——
The synthesis and resolution of a new axially chiral Quinazolinap ligand are reported. The application of this and other related P-N ligands to the copper catalyzed β-borylation of α,β-unsaturated esters resulted in conversions of up to 100% and ee values of up to 79%. A diastereomerically pure palladacycle of the new ligand was characterised by X-ray crystallography.
Synthesis and Post-Resolution Modification of New Axially Chiral Ligands for Asymmetric Catalysis
作者:William J. Fleming、Helge Müller-Bunz、Patrick J. Guiry
DOI:10.1002/ejoc.201000794
日期:2010.11
The synthesis of four new members of the Quinazolinap series of ligands is described. Three of these ligands were prepared by post-resolutionmodification of the known ligand (R)-7-chloro-2-isopropyl-Quinazolinap, a new approach which offers an expedient route to a range of enantiopure ligands as it precludes the need for resolution of each ligand prepared. The remaining ligand, 7-chloro-2-methyl-Quinazolinap