[reaction: see text] Readily tunable and bifunctional L-prolinamides as novel organocatalysts have been developed, and their catalytic activities were evaluated in the direct asymmetric Aldolreactions of various aromatic aldehydes and cyclohexanone. High isolated yields (up to 94%), enantioselectivities (up to 99% ee), and anti-diastereoselectivities (up to 99:1) were obtained under the optimal conditions
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
Monofunctional primary amine: A new class of organocatalyst for asymmetric Aldol reaction
作者:KHIANGTE VANLALDINPUIA、PORAG BORA、GHANASHYAM BEZ
DOI:10.1007/s12039-017-1237-y
日期:2017.3
organocatalysts involving a primaryamine as the only functional group is developed for catalytic asymmetric aldol reaction of cyclohexanone/cyclopentanone with various aryl aldehydes in the presence of benzoic acid as an additive at −10∘C. In an unexpected observation, the primaryamine catalyzed reactions gave excellent yield and good to excellent stereoselectivity, while secondary amines were found to have
Highly Enantioselective Direct Aldol Reactions Catalyzed by Proline Derivatives Based on a Calix[4]arene Scaffold in the Presence of Water
作者:Leyong Wang、Yi Pan、Zheng-Yi Li、Jia-Wen Chen
DOI:10.1055/s-0029-1217710
日期:2009.9
A series of proline-derived organocatalysts based on a calix[4]arene scaffold have been developed to catalyze direct aldol reactions in the presence of water. Under the optimal conditions, high yields (up to >99%), good enantioselectivities (up to >99% ee) and diastereoselectivities (up to 90:10) were obtained.
Simple and Facile l-Prolinamides Derived from Achiral Cycloalkylamines as Organocatalysts for the Highly Efficient Large-Scale Asymmetric Direct Aldol Reactions
simple catalyst can be efficiently used in large-scale reactions with the enantioselectivity being maintained at the same level, which offers great possibility for applications in industry.Graphical AbstractAll of the catalysts 1a–e synthesized fromachiral cycloalkylamines in a facile manner and their catalytic properties were studied in depth for the first time. All of the catalysts 1a–e exhibited great