Tandem Organocatalyzed Knoevenagel Condensation/1,3-Dipolar Cycloaddition towards Highly Functionalized Fused 1,2,3-Triazoles
作者:Jubi John、Joice Thomas、Nikita Parekh、Wim Dehaen
DOI:10.1002/ejoc.201500459
日期:2015.8
Facile synthesis of fused 1,2,3-triazoles by a proline-catalyzed reaction of an azido aldehyde and a nitroalkane is elaborated. The present tandem protocol proceeds via an organocatalytic Knoevenagel condensation of the azido aldehyde and nitroalkane followed by intramolecular azide–nitroalkene cycloaddition. The functionalized bicyclic triazole is obtained by elimination of HNO2 from the cycloadduct
详细阐述了通过叠氮醛和硝基烷烃的脯氨酸催化反应轻松合成稠合 1,2,3-三唑。本串联方案通过叠氮醛和硝基烷烃的有机催化 Knoevenagel 缩合,然后进行分子内叠氮化物-硝基烯烃环加成反应进行。通过从环加合物中消除 HNO2 获得官能化的双环三唑。这种策略的应用使我们能够合成一系列功能化的 5-7 元环稠合三唑。该反应需要温和的条件,提供高产率,并产生良好的区域特异性,同时显示出优异的底物范围。