<scp>l</scp>-Piperazine-2-carboxylic Acid Derived <i>N</i>-Formamide as a Highly Enantioselective Lewis Basic Catalyst for Hydrosilylation of <i>N</i>-Aryl Imines with an Unprecedented Substrate Profile
作者:Zhouyu Wang、Mounuo Cheng、Pengcheng Wu、Siyu Wei、Jian Sun
DOI:10.1021/ol060984i
日期:2006.7.1
l-Piperazine-2-carboxylic acid derived N-formamides have been developed as highlyenantioselectiveLewis basic catalysts for the hydrosilylation of N-aryl imines with trichlorosilane. The arene sulfonyl group on N4 was found to be critical for the high enantioselectivity of the catalyst. High isolated yields (up to 99%) and enantioselectivities (up to 97%) were obtained for a broad range of substrates, including
Synthesis of novel carbohydrate-based valine-derived formamide organocatalysts by CuAAC click chemistry and their application in asymmetric reduction of imines with trichlorosilane
作者:Xin Ge、Chao Qian、Xinzhi Chen
DOI:10.1016/j.tetasy.2014.10.003
日期:2014.11
organocatalysts combining carbohydrate and N-formyl-l-valine derivatives were prepared by CuII-catalyzed diazotransfer and CuI-catalyzed azide–alkyne 1,3-dipolar cycloaddition CuAACclickchemistry. It was found that the carbohydrate-based valine-derived formamide organocatalyst had high catalytic activity for the asymmetric reduction of imines with trichlorosilane. The reduction can proceed at room
Novel Amido-Complexes for the Efficient Asymmetric Hydrogenation of Imines
作者:Kathrin Kutlescha、Torsten Irrgang、Rhett Kempe
DOI:10.1002/adsc.201000733
日期:2010.12.17
Novel N,N,P ligand stabilized rhodium complexes exhibiting high activities and enantioselectivities in the asymmetrichydrogenation of N-aryl imines are introduced. The ligands were synthesized from inexpensive starting materials and their modular design allows for the introduction of a broad variety of substitution patterns. Additionally, a rather low catalyst loading could be employed.
Chiral N-heterocyclic carbene-iridium complexes for asymmetric reduction of prochiral ketimines
作者:Lakshay Kathuria、Ashoka G. Samuelson
DOI:10.1016/j.poly.2020.114976
日期:2021.2
phenylglycine derived chiral NHC was shown to give the best Ir catalyst and it also gave the maximum ee compared to catalysts prepared from other NHCs in this series. The opposite enantiomer of the reduction product was always obtained while using the Ir complex bearing a valine based NHC. The yields were consistently high with a variety of imine substrates having different steric and electronic demands
An efficient proline-based homogeneous organocatalyst with recyclability
作者:Qiang Li、Yuan Li、Jingdong Wang、Yingjie Lin、Zhonglin Wei、Haifeng Duan、Qingbiao Yang、Fuquan Bai、Yaoxian Li
DOI:10.1039/c7nj03912c
日期:——
organocatalyst was developed for the asymmetric reduction of imines. This catalyst could be separated by cyclodextrin-modified Fe3O4@SiO2 magnetic nanoparticles and then released back into a fresh reaction for use more than seven times. Furthermore, a new catalytic mechanism was proposed and investigated through theoretical calculations.
在这项工作中,开发了均相有机催化剂用于亚胺的不对称还原。该催化剂可通过环糊精改性的Fe 3 O 4 @SiO 2磁性纳米颗粒分离,然后释放回新鲜反应中使用七次以上。此外,提出了一种新的催化机理,并通过理论计算进行了研究。