<i>N</i>,2,3,4-Tetrasubstituted Pyrrolidines through Tandem Lithium Amide Conjugate Addition/Radical Cyclization/Oxygenation Reactions
作者:František Kafka、Radek Pohl、Ivana Císařová、Richard Mackman、Gina Bahador、Ullrich Jahn
DOI:10.1002/ejoc.201600621
日期:2016.8
Enantioselective syntheses of densely functionalized pyrrolidines deriving their chirality from (R)-1-(phenyl)ethylamine are reported. Allylic amines and β-substituted-α,β-unsaturated esters are used as the building blocks in this one-pot reaction. Single electron transfer (SET) oxidation served to merge the reactivities of anionic enolate and radical intermediates. Ferrocenium hexafluorophosphate
报告了从 (R)-1-(苯基) 乙胺衍生其手性的密集官能化吡咯烷的对映选择性合成。烯丙胺和 β-取代-α,β-不饱和酯用作该一锅反应的构建单元。单电子转移 (SET) 氧化有助于合并阴离子烯醇化物和自由基中间体的反应性。易于制备、储存和处理的二茂铁六氟磷酸被用作 SET 氧化剂,持久性自由基 TEMPO 用作氧化剂,引入受保护的羟基官能团,这被证明有利于进一步衍生。在目标四取代吡咯烷中实现了独有的 2,3-反式和高达 6:1 的 3,4-顺式/反式非对映选择性。