A new family of phosphine ligands bearing a bulky carbazolyl scaffold is described. With the combination of ligand 2a and Pd(OAc)2, difficult tri-ortho-substituted biaryl couplings are accomplished smoothly. In particular, the catalyst loading as low as 0.02 mol% of Pd for non-activated 2,6-disubstituted aryl chloride coupling can be achieved.
描述了一类新型
膦配体,这些
配体含有一个庞大的咔唲基骨架。通过结合
配体2a和Pd(OAc)2,成功实现了难以进行的三邻位取代
联苯偶联反应。特别是,对于非活化的2,6-二取代芳基
氯偶联反应,可以实现低至0.02mol%的
钯催化剂负载量。