Organocatalytic Stereoselective Synthesis of 3-Alkyl-3-hydroxy-2-oxindoles Catalyzed by Novel Water-compatible Axially Unfixed Biaryl-based Bifunctional Organocatalysts
作者:Hongwu Zhao、Wei Meng、Zhao Yang、Ting Tian、Zhihui Sheng、Hailong Li、Xiuqing Song、Yutong Zhang、Sen Yang、Bo Li
DOI:10.1002/cjoc.201400166
日期:2014.5
In this work, six novel axially unfixed biaryl‐based water‐compatible bifunctional organocatalysts were designed and synthesized for the organocatalytic access to a variety of 3‐alkyl‐3‐hydroxy‐2‐oxindole derivatives via aldol reactions in water. Organocatalyzed by 5a, the direct aldol reactions of isatins with enolisable ketones underwent readily in water, furnishing the structurally diverse 3‐al
在这项工作中,设计并合成了六种新型的轴向不固定的基于联芳基的水相容性双官能团有机催化剂,用于通过水中的羟醛反应有机催化获得各种3-烷基-3-羟基-2-氧吲哚衍生物。在5a的有机催化下,靛红与可缩酮的直接醇醛缩合反应在水中容易发生,从而提供了结构多样的3-烷基-3-羟基-2-氧吲哚,具有不同的立体选择性(高达99%dr和> 99%ee)。此外,假设进行的醛醇缩合反应有可能的过渡态,以阐明所观察到的3-烷基-3-羟基-2-氧吲哚的立体选择性。