Practical Highly Enantioselective Synthesis of Propargylamines through a Copper-Catalyzed One-Pot Three-Component Condensation Reaction
作者:Nina Gommermann、Paul Knochel
DOI:10.1002/chem.200501233
日期:2006.5.24
The one-potthree-componentreaction of terminal alkynes, aldehydes and secondary amines in the presence of copper(I) bromide/quinap is reported. The reaction scope has been determined and a broad variety of all three components has been used, which afforded the corresponding propargylamines in good to excellent yields and moderate to very good enantioselectivities. The reaction showed a strong positive
Readily Available Biaryl P,N Ligands for Asymmetric Catalysis
作者:Thomas F. Knöpfel、Patrick Aschwanden、Takashi Ichikawa、Takumi Watanabe、Erick M. Carreira
DOI:10.1002/anie.200461286
日期:2004.11.12
Diastereofacial π-Stacking as an Approach To Access an Axially Chiral P,N-Ligand for Asymmetric Catalysis
作者:Balaji V. Rokade、Patrick J. Guiry
DOI:10.1021/acscatal.6b03427
日期:2017.4.7
A phosphino-imidazoline (PHIM) ligand possessing axial chirality is prepared in a straightforward five-step synthesis. Configurational stability around the chiral axis is achieved by the diastereofacial pi-stacking between the pentafluorophenyl and the naphthalene rings. In particular, access to enantiopure ligand (S,S,R-a)-2a was realized by fractional crystallization of the corresponding similar to 3:1 atropdiastereomeric mixture. The preliminary application of ligand (S,S,R-a)-UCD-PHIM showed excellent activities in the enantioselective copper-catalyzed A3 coupling (ee's up to 98.1% and yields up to 98%).