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
Proline-Glycine Dipeptidic Derivatives of Chiral Phosphoramides as Organocatalysts for the Enantiodivergent Aldol Reaction of Aryl Aldehydes and Isatins with Cyclohexanone in the Presence of Water
(S)-proline-glycine dipeptides and incorporating a chiral phosphoramide fragment was accomplished. These chiral compounds catalyze the enantioselective aldol addition reaction of cyclohexanone to prochiral aryl aldehydes and isatins in the presence of water. These chiral organocatalysts represent some of the few proline-derived compounds capable to catalyze aldol-type addition of cyclohexanone to isatins, a C–C
Synthesis of a new chiral organocatalyst derived from (S)-proline containing a 1,2,4-triazolyl moiety and its application in the asymmetric aldol reaction. Importance of one molecule of water generated in situ
作者:Omar Sánchez-Antonio、Eusebio Juaristi
DOI:10.1016/j.tetlet.2019.151128
日期:2019.10
yield. Our triazolyl-containing heterocycle was evaluated as organocatalyst (10 mol% load, under neat reaction conditions) in the enantioselective aldolreaction between four different types of ketones and a variety of aryl aldehydes. Good results in terms of enantioselectivity and chemical yield were observed under solvent-free reaction conditions and in the absence of any additive. Evidence is provided
Evaluation of Amino Nitriles and an Amino Imidate as Organocatalysts in Aldol Reactions
作者:Nikolaos Vagkidis、Alexander J. Brown、Paul A. Clarke
DOI:10.1055/s-0039-1690150
日期:2019.11
and a tert-butyl l-proline imidate as organocatalysts for the aldolreaction have been evaluated. l-Valine nitrile was found to be a syn-selective catalyst, while l-proline nitrile was found to be anti-selective, and gave products in modest to good enantioselectivities. tert-Butyl l-proline imidate was found to be a very efficient catalyst in terms of conversion of starting reagents to products, and
Highly modular dipeptide-like organocatalysts for direct asymmetric aldol reactions in brine
作者:Xiao-Mu Hu、Dong-Xu Zhang、Sheng-Yong Zhang、Ping-An Wang
DOI:10.1039/c5ra07019h
日期:——
dipeptide-like organocatalysts derived from proline, amino acids and primaryamines have been prepared for directasymmetricaldolreactions between various aromatic aldehydes and acetone to afford aldol products in good yields (up to 82%) and moderate enantioselectivities (up to 67% ee) with only 1 mol% of catalyst-loading in brine. Under the same conditions, the directasymmetricaldolreactions of aromatic