Quinidine Thiourea-Catalyzed Aldol Reaction of Unactivated Ketones: Highly Enantioselective Synthesis of 3-Alkyl-3-hydroxyindolin-2-ones
作者:Qunsheng Guo、Mayur Bhanushali、Cong-Gui Zhao
DOI:10.1002/anie.201004161
日期:2010.12.3
New catalysis mechanism! The asymmetric aldol reaction of unactivated ketones and activated carbonyl compounds is realized with a quinidine‐derived thiourea catalyst (see scheme), and involves an enolate mechanism instead of the widely used enamine mechanism. With isatins as the substrate, the reaction can be applied to the enantioselective synthesis of biologically active 3‐hydroxyindolin‐2‐ones.
新的催化机制!未活化的酮和活化的羰基化合物的不对称醛醇反应是通过奎尼丁衍生的硫脲催化剂实现的(见方案),并且涉及烯醇机制而不是广泛使用的烯胺机制。以靛红为底物,该反应可用于对映选择性合成具有生物活性的 3-羟基吲哚-2-酮。