Chiral Ammonium Betaines: A Bifunctional Organic Base Catalyst for Asymmetric Mannich-Type Reaction of α-Nitrocarboxylates
作者:Daisuke Uraguchi、Kyohei Koshimoto、Takashi Ooi
DOI:10.1021/ja8041004
日期:2008.8.1
A chiral ammonium betaine, an intramolecular ion-pairing quaternary ammonium aryloxide 3, has been designed and its vast potential as an enantioselective organic base catalyst has been successfully demonstrated in the highly enantioselective direct Mannich-type reaction of alpha-substituted alpha-nitrocarboxylates 2 with various N-Boc imines 1. The present study provides a conceptually new approach
设计了一种手性铵甜菜碱,一种分子内离子对季铵芳氧化物 3,其作为对映选择性有机碱催化剂的巨大潜力已在 α 取代的 α-硝基羧酸盐 2 与各种 N-Boc 亚胺 1. 本研究为设计双功能手性季铵盐及其作为均相有机分子催化剂的用途提供了一种概念上的新方法。