Copper-catalyzed asymmetric allylic substitution with aryl and ethyl Grignard reagents
作者:Khalid B. Selim、Ken-ichi Yamada、Kiyoshi Tomioka
DOI:10.1039/b809140d
日期:——
Phenyl- and ethyl-magnesium bromides undergo regioselective asymmetricallylicsubstitution with high enantioselectivity under the catalysis of chiral amidophosphane-copper(I) complexes.
The asymmetricallylicsubstitution of allylphosphates with aryl‐ and alkenylboronates catalyzed by a copper/N‐heterocyclic carbene complex was developed and the γ‐substitution products were obtained with high enantioselectivity (see scheme). To account for the observed influence of the reaction parameters a possible catalytic cycle for this process was proposed.
作者:Damien Polet、Xavier Rathgeb、Caroline A. Falciola、Jean-Baptiste Langlois、Samir El Hajjaji、Alexandre Alexakis
DOI:10.1002/chem.200801879
日期:2009.1.19
We describe herein the development of the first iridium‐catalyzed allylic substitution using arylzinc nucleophiles. High enantioselectivities were obtained from the reactions, which used commercially available Grignardreagents as the starting materials. This methodology was also shown to be compatible with halogen/metal exchange reactions. Its synthetic potential is demonstrated by its application
Iridium-Catalyzed Asymmetric Allylic Substitution with Aryl Zinc Reagents
作者:Alexandre Alexakis、Samir El Hajjaji、Damien Polet、Xavier Rathgeb
DOI:10.1021/ol0713842
日期:2007.8.1
Thanks to iridium catalysis, arylzinc reagents undergo regioselective allylic substitution with very high enantioselectivity, when associated with phosphoramidite ligands.
作者:Khalid B. Selim、Yasumasa Matsumoto、Ken-ichi Yamada、Kiyoshi Tomioka
DOI:10.1002/anie.200904676
日期:2009.11.2
Gamma rules: The title reaction was achieved in a highly regioselective manner using aryl Grignardreagents with monodentate chiral N‐heterocyclic carbene–copper(I) catalyst to give diarylvinylmethanes with excellent enantiomeric excess in excellent yield (see scheme).