for the asymmetric Michael addition of aldehydes to nitroolefins with a catalytic system of organocatalyst 1 in combination with ionic-liquid-supported (ILS) benzoic acid in water has been developed. The Michael adducts of this system give excellent diastereo- and enantioselectivities. A notable feature of this organocatalytic system is that the catalyst can be recycled more than 12 times without significant
A highly efficient access to enantiopure tetrahydropyridines: dual-organocatalyst-promoted asymmetric cascade reaction
作者:Hua Lin、Yu Tan、Wen-Jie Liu、Zhi-Cheng Zhang、Xing-Wen Sun、Guo-Qiang Lin
DOI:10.1039/c3cc40690c
日期:——
A highly efficient cascade process of Michael–aza-Henry–hemiaminalization–dehydration was established for the construction of enantiopure tetrahydropyridines using the combination of prolinol trimethylsilyl ether and cinchona alkaloid catalysts. This new approach allowed for the application of aliphatic imines, generated in situ from aldehydes and amines. Good yields (up to 90%), high enantio- (up to >99% ee) and diastereoselectivities (>99 : 1 d.r. in all cases) were achieved for a broad spectrum of substrates under mild conditions.
Ionic Liquid-Supported (ILS) (S)-Pyrrolidine Sulfonamide for Asymmetric Michael Addition Reactions of Aldehydes with Nitroolefins
作者:Emmy M. Omar、Kritanjali Dhungana、Allan D. Headley、Mohd Basyaruddin Abdul Rahman
DOI:10.2174/157017811795038395
日期:2011.3.1
supported (ILS) (S)-pyrrolidine sulfonamide organocatalyst (1c), which was developed earlier in our lab, has been applied to a wider range of Michaeladditionreaction, involving various aryl-substituted nitroolefins and a series of aldehydes. Catalyst 1c catalyzes Michaeladditions in which only 2 equivalents of aldehydes to each equivalent of nitroolefin are required. With 10 mol% of ILS catalyst
Asymmetric Organocatalysis Accelerated via Self‐Assembled Minimal Structures
作者:Arianna Sinibaldi、Francesca Della Penna、Marco Ponzetti、Francesco Fini、Silvia Marchesan、Andrea Baschieri、Fabio Pesciaioli、Armando Carlone
DOI:10.1002/ejoc.202101042
日期:2021.10.21
Self-assembling minimalistic peptides embedded with an organocatalytic moiety were designed and tested in a Michael reaction as a proof of concept for acceleratedorganocatalysis.
嵌入有机催化部分的自组装简约肽在迈克尔反应中被设计和测试,作为加速有机催化的概念证明。
A Recyclable Fluorous (<i>S</i>)-Pyrrolidine Sulfonamide Promoted Direct, Highly Enantioselective Michael Addition of Ketones and Aldehydes to Nitroolefins in Water
作者:Liansuo Zu、Jian Wang、Hao Li、Wei Wang
DOI:10.1021/ol061053+
日期:2006.7.1
[reaction: see text] A recycle and reusable fluorous (S)-pyrrolidine sulfonamide organocatalyst has been developed for promoting highly enantio- and diastereoselective Michael addition reactions of ketones and aldehydes with nitroolefins in water. The organocatalyst is conveniently recovered from the reaction mixtures by fluorous solid-phase extraction and can be subsequently reused (up to six cycles) without