A novelbifunctional organocatalyst library combining both aminocatalysis and phosphonicacid activation was used for the first time as an efficient tool for the stereoselectiveMichaeladdition of aldehydes with several aromatic nitroalkenes with good selectivities up to 95:5 dr and 93:7 er. Due to their high water solubility, the catalysts were easilyrecyclable and could be reused over several cycles
Effective and recyclable dendritic catalysts for the direct asymmetric Michael addition of aldehydes to nitrostyrenes
作者:Yawen Li、Xin-Yuan Liu、Gang Zhao
DOI:10.1016/j.tetasy.2006.07.004
日期:2006.8
Direct catalytic enantio- and diastereoselective Michael addition reaction of aldehydes to nitrostyrenes is described using a series of recyclable chiral 2-trimethylsilanyloxy-methyl-pyrrolidine-based dendritic catalysts. Good yields (up to 82%), and high diastereoselectivities (up to syn/anti = 95/5) and enantioselectivities (up to 99% ee) have been obtained.
使用一系列可循环使用的手性2-三甲基甲硅烷基氧基-甲基-吡咯烷基树枝状催化剂描述了醛与硝基苯乙烯的直接催化对映和非对映选择性迈克尔加成反应。获得了良好的收率(高达82%),高的非对映选择性(高达syn / anti = 95/5)和对映选择性(高达99%ee)。
The Use ofN-Alkyl-2,2′-bipyrrolidine Derivatives as Organocatalysts for the Asymmetric Michael Addition of Ketones and Aldehydes to Nitroolefins
The direct Michaeladdition of aldehydes and ketones to nitroolefins, catalyzed by N-i-Pr-2,2′-bipyrrolidine, is described. The desired 1,4-adducts are obtained in excellent yields with enantioselectivities up to 95% ee and dr up to 95 : 5 of the syn aldehydeaddition product. An unexpected inversion of diastereoselectivity was observed for the addition of α-hydroxy ketones to β-arylnitroolefins with
Novel Octapeptide as an Asymmetric Catalyst for Michael Reaction in Aqueous Media
作者:Saadi Bayat、Emilia Abdulmalek、Bimo Ario Tejo、Abu Bakar Salleh、Yahaya M. Normi、Mohd Basyaruddin Abdul Rahman
DOI:10.1080/00397911.2012.762686
日期:2013.12.2
this work, three forms of a novel octapeptide have been evaluated as asymmetric catalysts for the Michaelreaction. Low quantity catalyst loading, ecofriendly solvents, and reusability of organocatalyst successfully applied to attain excellent yields and moderate enantioselectivities in the Michaelreaction. [Supplementary materials are available for this article. Go to the publisher's online edition
Asymmetric Organocatalytic Cascade Michael/Michael/Henry Reaction Sequence: Control of All Stereocenters in One Cyclohexane Skeleton
作者:Zhifeng Mao、Yaomei Jia、Zhaoqing Xu、Rui Wang
DOI:10.1002/adsc.201200008
日期:2012.5.21
The highly diastereo‐ and enantioselective relay cascade Michael/Michael/Henryreaction catalyzed by combination of readily available diphenylprolinolsilylether and the quinine thiourea in a one‐pot fashion has been developed. Up to 70% yield and up to >99% enantioselectivity of the single major isomer were obtained from the cascade reactions.
已经开发出了一种高非对映选择性和对映选择性中继级联Michael / Michael / Henry反应,该反应通过容易获得的二苯基脯氨醇甲硅烷基醚和奎宁硫脲的单锅法进行催化。从级联反应中获得了单一主要异构体的最高70%的收率和最高> 99%的对映选择性。