Practical Synthesis of 2-Arylacetic Acid Esters via Palladium- Catalyzed Dealkoxycarbonylative Coupling of Malonates with Aryl Halides
作者:Bingrui Song、Felix Rudolphi、Thomas Himmler、Lukas J. Gooßen
DOI:10.1002/adsc.201100102
日期:2011.6
A new palladium‐based system was developed that catalyzes the coupling of aryl halides with diethyl malonates in the presence of mild bases. In the course of the reaction, the intermediately formed diethyl arylmalonate is directly converted into the arylacetic acid ester via liberation of carbon dioxide and an alkanol. This cross‐coupling/dealkoxycarbonylation process provides an efficient and high‐yielding
开发了一种新的基于钯的系统,该系统在弱碱存在下催化芳基卤化物与丙二酸二乙酯的偶联。在反应过程中,通过释放二氧化碳和链烷醇,将中间形成的芳基丙二酸二乙酯直接转化为芳酸酯。这种交叉偶联/脱烷氧羰基化工艺为各种功能化的芳基丙烯酸酯提供了高效且高产的合成入口。开发了两种互补的方案,其中一种对富电子的是最佳的,另一种对贫电子的芳基卤化物是最佳的。两者均使用低负载量的钯(0)双(二亚苄基丙酮)(0.5 mol%)/三叔-四氟硼酸叔丁基((1.1 mol%)作为催化剂,丙二酸二乙酯作为反应溶剂。新程序对于空间受阻的基材特别有效。