Green Catalysts: Solid-Phase Peptide Carbene Ligands in Aqueous Transition-Metal Catalysis
作者:Kasper Worm-Leonhard、Morten Meldal
DOI:10.1002/ejoc.200800633
日期:2008.11
functionalized imidazolium ions containing a pyridine moiety and carboxylic acid functionality has been synthesized in solution. These compounds serve as N-heterocyclic carbene precursors and were attached to a dipeptide on solid support by means of standard peptide coupling techniques. Treatment with base generated the corresponding carbenes, which were directly complexed to palladium(II) and subsequently studied
已经在溶液中合成了一系列含有吡啶部分和羧酸官能团的官能化咪唑鎓离子。这些化合物用作 N-杂环卡宾前体,并通过标准肽偶联技术连接到固体支持物上的二肽上。用碱处理产生相应的卡宾,它们直接与钯 (II) 络合,随后通过质谱和核磁共振光谱进行研究。负载型单卡宾催化剂7成功应用于Sonogashira和Suzuki交叉偶联反应,并以优异的收率分离出交叉偶联产物。双(卡宾)催化剂 8 成功应用于高产铃木交叉偶联反应的溶液中。此外,该催化剂被证明在水性介质中是稳定的,这使得铃木交叉偶联反应可以在水中进行。当负载型催化剂 7 被回收并在水中进行 Suzuki 交叉偶联反应的重复循环时,没有观察到催化活性的损失。 (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)