Copper(I) Acetate-Catalyzed Cycloaddition between Azomethine Imines and Propiolates under Additive-Free Conditions
作者:Changwei Shao、Qun Zhang、Guolin Cheng、Chuanjie Cheng、Xinyan Wang、Yuefei Hu
DOI:10.1002/ejoc.201300753
日期:2013.10
Because propiolates easily undergo base-catalyzed self-Michael addition, most popular catalytic systems in CuAAC cannot be used in the cycloaddition between azomethine imines and propiolates, because such reactions usually require the use of tertiary amines as additives (as base and/or ligand). We found that this problem can be resolved simply by using copper(I) acetate as catalyst, in which the acetate
由于丙炔化物容易进行碱催化自迈克尔加成,CuAAC 中最流行的催化体系不能用于偶氮甲亚胺和丙炔化物之间的环加成,因为此类反应通常需要使用叔胺作为添加剂(作为碱和/或配体) . 我们发现这个问题可以简单地通过使用乙酸铜(I)作为催化剂来解决,其中乙酸作为配体并在反应过程中转化为乙酸。因此,乙酸铜 (I) 催化的环加成反应实际上是在无添加剂的条件下(没有外源配体)有效地得到 6,7-二氢吡唑并[1,2-a] 吡唑啉酮衍生物,其中由碱性引起的副反应和副产物完全避免添加剂。