Study of a new rate increasing "Base effect" in the palladium-catalyzed amination of aryl iodides
Study of a new rate increasing "Base effect" in the palladium-catalyzed amination of aryl iodides
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DOI：
10.1021/jo049774e
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发表时间：
2004-09-03
影响因子：
3.6
通讯作者：
Dommisse, RA
中科院分区：
文献类型：
--
作者：
Meyers, C;Maes, BUW;Dommisse, RA
第一次获得了Pd（II）-胺络合物与弱碳酸盐碱的相间去质子化的证据。当在催化循环中涉及限速去质子化步骤时，控制所用碳酸酯碱的结构（颗粒的形状和尺寸）和/或摩尔过量可以显著增加Buchwald-Hartwig胺化的反应速率。通过考虑这种“碱效应”，基于标准Pd-BINAP催化剂，使用碳酸铯作为碱，已经开发了用于芳基碘与所有类型的胺的分子间胺化的通用方案。
Evidence for an interphase deprotonation of Pd(II)-amine complexes with weak carbonate base has been gained for the first time. When a rate-limiting deprotonation step is involved in the catalytic cycle, controlling the structure (shape and size of the particles) and/or molar excess of the carbonate base used can significantly increase the reaction rate of Buchwald-Hartwig aminations. By taking such a "base effect" into account a general protocol for the intermolecular amination of aryl iodides with all types of amines has been developed based on a standard Pd-BINAP catalyst, using cesium carbonate as the base.