Synthesis and Characterization of Monosaccharide Derivatives and Application of Sugar-Based Prolinamides in Asymmetric Synthesis
作者:Jyoti Agarwal、Rama Krishna Peddinti
DOI:10.1002/ejoc.201200522
日期:2012.11
were converted into the corresponding prolinamide organocatalysts (i.e., 1a, 2a, 3a, and 3b) in high yields. The catalytic activity of these sugar-based prolinamide organocatalysts was demonstrated in asymmetric aldol reactions in various solvents and at different temperatures. The oraganocatalyst 3a was shown to be an efficient and powerful organocatalyst for the enantioselective aldol reaction of various
Dipeptide-catalyzed direct asymmetric aldol reactions in the presence of water
作者:Meng Lei、Lanxiang Shi、Gong Li、Shilv Chen、Weihai Fang、Zemei Ge、Tieming Cheng、Runtao Li
DOI:10.1016/j.tet.2007.05.077
日期:2007.8
dipeptide has been discovered and developed as an efficient catalyst for the directasymmetricaldolreactions of unmodified ketones with various aldehydes including aromatic, aliphatic, heteroaromatic, and unsaturated aldehydes in the presence of water at 0 °C. The resulted methodology and optimal conditions led to the corresponding aldol products with high yields (up to 94%) and good enantioselectivities
Enzyme-catalyzed synthesis reactions are of crucial importance for a wide range of applications. An accurate and rapid selection of optimal synthesis conditions is crucial and challenging for both human knowledge and computer predictions. In this work, a new scenario, which combines a data-driven machinelearning (ML) model with reactivity descriptors, is developed to predict the optimal enzyme-catalyzed
New Simple Hydrophobic Proline Derivatives as Highly Active and Stereoselective Catalysts for the Direct Asymmetric Aldol Reaction in Aqueous Medium
作者:Francesco Giacalone、Michelangelo Gruttadauria、Paolo Lo Meo、Serena Riela、Renato Noto
DOI:10.1002/adsc.200800555
日期:——
different hydrophobic properties of the acyl group were easily synthesized and used as catalysts in the direct asymmetric aldolreaction between cyclic ketones (cyclohexanone and cyclopentanone) and several substituted benzaldehydes. Reactions were carried out using water, this being the best reaction medium examined. Screening of these catalysts showed that compounds bearing the most hydrophobic acyl
A Highly Efficient, Large-Scale, Asymmetric Direct Aldol Reaction Employing Simple Threonine Derivatives as Recoverable Organocatalysts in the Presence of Water
作者:Chuanlong Wu、Xiangkai Fu、Shi Li
DOI:10.1002/ejoc.201001396
日期:2011.3
A one-step O-acylation of threonine resulted in a simple and readily available threonine-surfactant organocatalyst that could efficiently catalyze the direct asymmetric aldol reactions of cyclic and acyclic ketones with a series of aromatic aldehydes in the presence of water at room temperature with good yields (up to 99 %), diastereoselectivities (up to 99:1), and enantiomeric excesses (>99 %). The