“On Water” Catalytic Aldol Reaction between Isatins and Acetophenones: Interfacial Hydrogen Bonding and Enamine Mechanism
作者:Jinsong Han、Jin-Lei Zhang、Wei-Qiang Zhang、Ziwei Gao、Li-Wen Xu、Yajun Jian
DOI:10.1021/acs.joc.9b00441
日期:2019.6.21
“On water” catalytic aldol reaction catalyzed by polyetheramine (D230) has been developed for easy access to 3-substituted 3-hydroxyindolin-2-ones through the reaction between various substituted isatins and acetophenones/cyclic ketones in high yields under room temperature. Systematic mechanism investigation uncovers the secret for the on water catalytic aldol reaction: comparison of the heterogeneous
已经开发了通过聚醚胺(D230)催化的“水上”催化醛醇缩合反应,可通过在室温下高产率地使各种取代的靛红与乙酰苯/环酮之间的反应轻松获得3-取代的3-羟基吲哚-2-酮。系统的机理研究揭示了水催化醛醇缩合反应的奥秘:比较异构反应和均相反应的情况,产率分别为95%和20%,表明水上反应占主导。当将水添加到CDCl 3中时,基于C2和C3的13 C NMR信号的下场位移,测试了isatin与H 2 O之间的界面氢键靛红溶液;路易斯碱聚醚胺D230通过烯胺机制催化醛醇缩醛反应,该机制已通过原位NMR和ESI-MS分析验证。