Organo-catalyzed highly diastereo- and enantio-selective direct aldol reactions in water
作者:Jun-Feng Zhao、Long He、Jun Jiang、Zhuo Tang、Lin-Feng Cun、Liu-Zhu Gong
DOI:10.1016/j.tetlet.2008.03.131
日期:2008.5
The asymmetric directaldolreactions of a wide scope of aromatic aldehydes, with unmodified ketones in the presence of 1 mol % of organocatalyst prepared from (2R,3R)-diethyl 2-amino-3-hydroxysuccinate and trans-4-hydroxy-l-proline, were performed in water, affording aldol products in high yields with excellent diastereoselectivities of up to >99:1 and enantioselectivities of up to 98%.
(1R,2R)-Bis[(S)-prolinamido]cyclohexane Modified with Ionic Groups: The First C2-Symmetric Immobilized Organocatalyst for Asymmetric Aldol Reactions in Aqueous Media
作者:Sergei V. Kochetkov、Alexandr S. Kucherenko、Sergei G. Zlotin
DOI:10.1002/ejoc.201100707
日期:2011.10
The first C2-symmetric immobilized organocatalyst for asymmetricaldolreactions containing the (1R,2R)-bis[(S)-prolinamido]cyclohexane unit tagged with two imidazolium+/PF6– ion pairs has been synthesized. In its presence, (hetero)aromatic aldehydes reacted with linear or cyclicketones in aqueous media to yield chiral aldols with high diastereo- and enantioselectivities and the catalyst could be
Combining prolinamides with 2-pyrrolidinone: Novel organocatalysts for the asymmetric aldol reaction
作者:Ismini Vlasserou、Maria Sfetsa、Dimitrios-Triantafyllos Gerokonstantis、Christoforos G. Kokotos、Panagiota Moutevelis-Minakakis
DOI:10.1016/j.tet.2018.03.054
日期:2018.5
identified as excellent organocatalysts for the aldolreaction. The combination of prolinamides with derivatives bearing the 2-pyrrolidinone scaffold, deriving from pyroglutamic acid, led to the identification of novel organocatalysts for the intermolecular asymmetricaldolreaction. The new hybrids were tested both in organic and aqueous media. Among the compounds tested, 22 afforded the best results in petroleum
New simple and recyclable O-acylation serine derivatives as highly enantioselective catalysts for the large-scale asymmetric direct aldol reactions in the presence of water
作者:Chuanlong Wu、Xiangkai Fu、Shi Li
DOI:10.1016/j.tet.2011.03.083
日期:2011.6
products in high yields (up to 99%) and enantioselectivities (up to 99% ee). The catalyst 1b can be easily recovered and reused, and without significant decrease of enantioselectivity was observed for five cycles. This novel catalyst can be efficiently used in large-scale reactions with the enantioselectivities being maintained at the same level, which offers a great possibility for application in industry
Novel prolinamide–ureas as organocatalysts for the asymmetric aldol reaction
作者:Panagiota Revelou、Christoforos G. Kokotos、Panagiota Moutevelis-Minakakis
DOI:10.1016/j.tet.2012.08.023
日期:2012.10
versions of the aldolreaction, the enantioselective reaction between cyclicketones and aldehydes constitutes a typical reaction model for the evaluation of novel organocatalysts. A multifunctional organocatalyst consisting of a prolinamide moiety, a gem diamine unit and a urea group was successfully employed in this asymmetric transformation. The products of the reaction between various ketones and aldehydes