A polystyrene-supported 9-amino(9-deoxy)epi quinine derivative for continuous flow asymmetric Michael reactions
作者:Javier Izquierdo、Carles Ayats、Andrea H. Henseler、Miquel A. Pericàs
DOI:10.1039/c5ob00325c
日期:——
derivative catalyzes Michael reactions affording excellent levels of conversion and enantioselectivity using different nucleophiles and structurally diverse enones. The highly recyclable, immobilized catalyst has been used to implement a single-pass, continuous flow process (residence time: 40 min) that can be operated for 21 hours without significant decrease in conversion and with improved enantioselectivity
Preliminary studies of the elementary steps involved in the reaction of a chiral methyl carbonyl bioxazoline Pd(II) complex with aromatic olefins and CO have allowed development of a new enantioselective catalytic carbonylation process, leading to γ-ketoester derivatives with high yield and good enantiomeric excess. The intermediate palladacycle complexes have been isolated and characterized by NMR
Enantioselective Synthesis of α-Stereogenic γ-Keto Esters via Formal Umpolung
作者:G. K. Surya Prakash、Fang Wang、Zhe Zhang、Chuanfa Ni、Ralf Haiges、George A. Olah
DOI:10.1021/ol301112m
日期:2012.7.6
feasible method has been developed for the enantioselective synthesis of α-stereogenic γ-keto esters. By employing nitro(phenylsulfonyl)methane as an acyl anion equivalent, the integrated Michael addition reaction-oxidative methanolysis protocol allows the preparation of various γ-keto esters with high optical purities.