Magnetic nanoparticles supported cinchona alkaloids for asymmetric Michael addition reaction of 1,3-dicarbonyls and maleimides
作者:Shi-Xuan Cao、Jia-Xi Wang、Zheng-Jie He
DOI:10.1016/j.cclet.2017.06.022
日期:2018.1
Abstract Magnetic nanoparticles Fe3O4@SiO2 supported cinchonaalkaloids (quinine and quinidine) were successfully synthesized as magnetically recoverable organocatalysts and characterized by FT-IR, XPS, SEM measurements, and elemental analysis. Their catalytic activity and stereoselectivity were preliminarily evaluated in the asymmetric Michael addition reaction of 1,3-dicarbonyls and maleimides. The
Construction of Adjacent Quaternary and Tertiary Stereocenters by Conjugate Addition Using Polymer-Supported Cinchona Alkaloids as Catalysts
作者:Yanyan Qin、Gengxu Yang、Lili Yang、Jia Li、Yuanchen Cui
DOI:10.1007/s10562-010-0509-7
日期:2011.3
alkaloids have been used as the catalysts for the asymmetric Michael reaction of 1,3-dicarbonyl compounds and N-benzylmaleimide. The corresponding asymmetric Michael addition product, the first example of adjacentquaternary and tertiarystereocenters synthesized in the presence of a polymer-bound catalyst, has a selectivity of up to 86% ee. Besides, immobilized alkaloid V retains stereochemical reactivity
已经制备了一系列聚合物结合的金鸡纳生物碱。所得聚合物结合的金鸡纳生物碱已用作 1,3-二羰基化合物和 N-苄基马来酰亚胺的不对称迈克尔反应的催化剂。相应的不对称迈克尔加成产物是在聚合物键合催化剂存在下合成的相邻季和叔立体中心的第一个例子,其选择性高达 86% ee。此外,固定化生物碱V在循环使用6次后仍保持立体化学反应活性。图文摘要制备了一系列聚合物结合的金鸡纳生物碱。所得聚合物结合的金鸡纳生物碱已用作 1,3-二羰基化合物和 N-苄基马来酰亚胺的不对称迈克尔反应的催化剂。相应的不对称迈克尔加成产物,在聚合物结合的催化剂存在下合成的相邻四级和三级立体中心的第一个例子具有高达 86% ee 的选择性。此外,固定化生物碱V即使在循环使用六次后仍保持立体化学反应性。
Chitosan-Based Heterogeneous Catalysts for Enantioselective Michael Reaction
作者:Yanyan Qin、Wenshan Zhao、Lili Yang、Xuan Zhang、Yuanchen Cui
DOI:10.1002/chir.22058
日期:2012.8
Novel chitosan‐supported cinchona alkaloids have been developed as heterogeneouscatalysts for enantioselectiveMichaelreaction. As‐synthesized products as organocatalysts for asymmetric Michaelreaction have a high efficiency, providing highly functionalized products (containing adjacent quaternary and tertiary stereocenters) with good stereoselectivity (up to 93% enantiomeric excess) in high yields
Carboxymethylcellulose Supported Cinchonine as a Recyclable Catalyst for Asymmetric Michael Reaction
作者:Lili Yang、Dapeng Zhou、Chengke Qu、Yuanchen Cui
DOI:10.1007/s10562-012-0915-0
日期:2012.11
A novel cinchonine catalyst supported by carboxymethylcellulose (CMC) has been prepared with a simple approach. As-prepared CMC-supported cinchonine catalyst was used to catalyze the asymmetric Michael addition of 1,3-dicarbonyl compounds to N-benzylmaleimide at a very low loading (3 mol%). It has been found that desired adducts containing adjacent quaternary and tertiary stereocenters can be obtained in high efficiency (yield 80 %) and stereoselectivity (dr 75:25, ee 78 %). Moreover, as-prepared catalyst possesses good recyclability (at least 4 times).
Catalytic Performance of Silica Supported Cinchona Alkaloids as Heterogeneous Catalysts for Asymmetric Michael Reaction
作者:Wenshan Zhao、Yanli Zhang、Chengke Qu、Lei Zhang、Jing Wang、Yuanchen Cui