作者:Ting Ma、Xiao Fu、Choon Wee Kee、Lili Zong、Yuanhang Pan、Kuo-Wei Huang、Choon-Hong Tan
DOI:10.1021/ja1098353
日期:2011.3.9
A new chiral entity, pentanidium, has been shown to be an excellent chiralphase-transfercatalyst. The enantioselective Michaeladdition reactions of tert-butyl glycinate-benzophenone Schiff base with various α,β-unsaturated acceptors provide adducts with high enantioselectivities. A successful gram-scale experiment at a low catalyst loading of 0.05 mol % indicates the potential for practical applications
Transforming Racemic Compounds into Two New Enantioenriched Chiral Products via Intermediate Kinetic Resolution
作者:Jian Zhang、Mingyang Song、Weijun Tang、Dong Xue、Jianliang Xiao、Huaming Sun、Chao Wang
DOI:10.1021/acscatal.3c04599
日期:2023.12.1
Converting racemic compounds to enantioenriched products is an important and economic approach for accessing enantioenriched chiral molecules. A common method is kineticresolution. Herein, we present a mode of kineticresolution that transforms racemic compounds into enantioenriched products, in which the kineticresolution of reaction intermediates is the key. Catalyzed by a single Ru complex, racemic
将外消旋化合物转化为对映体富集的产物是获得对映体富集的手性分子的重要且经济的方法。一种常见的方法是动力学拆分。在此,我们提出了一种将外消旋化合物转化为对映体富集产物的动力学拆分模式,其中反应中间体的动力学拆分是关键。在单一 Ru 配合物的催化下,外消旋烯丙醇与甘氨酸衍生的席夫碱反应,生成两种手性化合物,即 δ-羰基产物和 δ-羟基变体,具有良好的产率和立体选择性(高达 >20: 1 dr,99% ee,920 s 因子)。机理研究表明,反应中存在多个氢转移事件:脱氢偶联过程,产生一对外消旋中间体,以及转移氢化驱动的动力学拆分过程,分解中间体,同时在催化剂上释放 H 2 。
NOVEL PHASE TRANSFER CATALYSTS
申请人:National University of Singapore
公开号:EP2632917B1
公开(公告)日:2016-04-20
A powerful synergistic effect for highly efficient diastereo- and enantioselective phase-transfer catalyzed conjugate additions
作者:Ming-Qing Hua、Lian Wang、Han-Feng Cui、Jing Nie、Xiao-Ling Zhang、Jun-An Ma
DOI:10.1039/c0cc04321d
日期:——
An efficient, catalytic, diastereo- and enantioselective conjugate addition of N-(diphenylmethylene)glycine tert-butyl ester to β-aryl substituted enones was realized in the presence of 1 mol% of newly desired dinuclear N-spiro-ammonium salts, affording functionalized α-amino acid derivatives in 57–98% yields with high diastereoselectivity (up to 99 : 1 dr) and enantioselectivity (up to 96.5 : 3.5 er).