Asymmetric Aldol Reaction Catalyzed by the Anion of an Ionic Liquid
作者:Vincent Gauchot、Andreea R. Schmitzer
DOI:10.1021/jo300737u
日期:2012.6.1
its applications as a catalyst for the asymmetric aldolreaction. By performing the aldolreaction in [Bmim]NTf2 as a solvent, we report excellent isolated yields of the aldol product (up to 99%), as well as modest to excellent selectivities (dr superior to 99:1. ee up to 89%). Mechanistic insights and the origins of the selectivity of the aldolreaction are discussed on the basis of the results obtained
Novel Axially Unfixed Biaryl-Based Water-Compatible Organocatalysts: Design, Synthesis and Their Asymmetric Catalysis in Direct Aldol Reactions in Water
作者:Hong-Wu Zhao、Yuan-Yuan Yue、Hai-Long Li、Xiu-Qing Song、Zhi-Hui Sheng、Zhao Yang、Wei Meng、Ze Yang
DOI:10.1055/s-0033-1339497
日期:——
A family of novelaxiallyunfixedbiaryl-based, water-compatiblebifunctionalorganocatalysts were designed and synthesized for asymmetric catalytic direct aldol reactions in water. These organocatalysts are comprised of prolinamide, aromatic sulfonamide and biaryl motifs. Under the optimal reaction conditions, one organocatalyst in particular delivered excellent stereocontrol (up to 99% ee and 99:1
设计并合成了一系列新型轴向未固定联芳基、水相容的双功能有机催化剂,用于在水中进行不对称催化直接醛醇反应。这些有机催化剂由脯氨酰胺、芳族磺酰胺和联芳基基序组成。在最佳反应条件下,特别是一种有机催化剂在环己酮与水中多种芳香醛的直接醛醇反应中提供了出色的立体控制(高达 99% ee 和 99:1 dr)。
Different bio/Lewis acid-catalyzed stereoselective aldol reactions in various mediums
作者:Tülay Yıldız、Hasniye Yaşa、Belma Hasdemir、Ayşe S. Yusufoğlu
DOI:10.1007/s00706-017-1967-z
日期:2017.8
Brønsted acids were used for asymmetric aldol reactions of aromatic, heteroaromatic, cyclic, and acyclic six ketones and eleven aldehydes. Optimum reaction conditions were determined by changing temperature and enzyme, ketone, aldehyde, solvent, cofactors types, amounts, and ratios. PPL (porcine pancreatic lipase) of animal and AL-AN (amano lipase A from Aspergillus niger) of fungal origins were the
Direct asymmetric aldol reactions between aldehydes and ketones catalyzed by l-tryptophan in the presence of water
作者:Zhaoqin Jiang、Hui Yang、Xiao Han、Jie Luo、Ming Wah Wong、Yixin Lu
DOI:10.1039/b921460g
日期:——
Primary amino acids and their derivatives were investigated as catalysts for the direct asymmetric aldol reactionsbetween ketones and aldehydes in the presence of water, and L-tryptophan was shown to be the best catalyst. Solvent effects, substrate scope and the influence of water on the reactions were investigated. Quantum chemical calculations were performed to understand the origin of the observed
(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