CaCl2, Bisoxazoline, and Malonate: A Protocol for an Asymmetric Michael Reaction
摘要:
A mild protocol for the asymmetric Michael addition of dimethyl malonate to various alpha,beta-unsaturated carbonyl compounds was developed. The salient feature of this methodology is that a cheap and environmentally friendly Lewis acid, CaCl2, was used as a catalyst. An aminoindanol- and pyridine-derived ligand provided in the presence of CaCl2 Michael adducts in moderate to high enantioselectivities. The scope of the reaction was demonstrated.
used as an aza-Michael donor in organocatalyticasymmetricreactions with symmetric and nonsymmetric unsaturated 1,4-diketones. After hydrolysis (in situ), the N-substituted isatins were obtained in high yields (up to >95%) with high enantioselectivity (up to 95%). Isatin was activated by derivatization to a Schiff base with aniline and used as an aza-Michael donor in organocatalyticasymmetric reactions
Umsetzungen mit Nitroenaminen, XI. Synthese von gesättigten und ungesättigten 1,4‐Dicarbonyl‐verbindungen
作者:Theodor Severin、Dieter König
DOI:10.1002/cber.19741070510
日期:1974.5
Ketone mit α-ständiger Methyl- oder Methylengruppe lassen sich mit 1-Dimethylamino-2-nitro-1-propen in Gegenwart von Basen zu aci-Nitropropyliden-Derivaten umsetzen (5 + 6 7). Diese aci-Nitro-Ketone werden auf Kieselgel in die entsprechenden 1,4-Dicarbonylverbindungen 9 umgewandelt. Andere Methoden zur Darstellung von 9 aus 7 wie Oxidation mit Peroxodisulfat oder Reduktion mit Ascorbinsäure bringen
Organocatalytic Enantioselective Direct Vinylogous Michael Addition of α,β-Unsaturated γ-Butyrolactam to β-Acyl Acrylates and 1,2-Diacylethylenes
作者:Yi-Ru Chen、Utpal Das、Meng-Hsien Liu、Wenwei Lin
DOI:10.1021/jo5027047
日期:2015.2.6
A highly efficient Michaeladdition of α,β-unsaturated γ-butyrolactam to various β-acyl acrylates and ene-diones to provide synthetically useful compounds was developed. The products were obtained with high diastereo- and enantioselectivities (up to >25:1 dr and 99% ee) containing adjacent tertiary stereocenters.
Design, Synthesis and Application of Multifunctional Chiral Aminophosphine Catalyst for Asymmetric Intermolecular Cross
<scp>Rauhut‐Currier</scp>
Reaction
作者:Wu‐Wei Dong、Kui Tian、Xiu‐Qin Dong、Chun‐Jiang Wang
DOI:10.1002/cjoc.202200205
日期:2022.9
novel multifunctional chiral aminophosphine catalysts were developed through a concise synthetic strategy from easily available starting materials. The highly enantioselective intermolecular cross Rauhut-Currier reactions of vinyl ketones with 3-acyl acrylates and 2-ene-1,4-diones catalyzed by (S,S)-5a were well realized, generating a wide range of the structurally important chiral multicarbonyl products
一系列结构新颖的多功能手性氨基膦催化剂是通过简单的合成策略从容易获得的起始材料中开发出来的。( S , S )-5a催化的乙烯基酮与 3-酰基丙烯酸酯和 2-ene-1,4-二酮的高度对映选择性分子间交叉 Rauhut-Currier 反应得到了很好的实现,产生了结构上重要的手性多羰基化合物具有高立体控制(高达 97% 的产率,99% ee)的产品。此外,还进行了一系列31 P NMR 实验以进一步研究催化过程。