尽管人们越来越关注在催化中利用一种以上金属的协同效应,但除双金属体系外,人们所知甚少。该报告描述了直接进入空气稳定的Pd三聚体的方法,并提供了明确的反应性数据,该数据具有在多卤代芳烃的C-C键形成(芳构化和烷基化)中区分C-1与C-Br键的特权。0和Pd I -Pd I催化剂无法输送。给出了实验和计算反应性数据,包括三聚体激活键的过渡态的第一个位置,支持直接的三聚体反应性是可行的。
Carboxylic Acids as Traceless Directing Groups for Formal meta-Selective Direct Arylation
作者:Josep Cornella、Marika Righi、Igor Larrosa
DOI:10.1002/anie.201103720
日期:2011.9.26
Without a trace: The first meta‐selective direct CH arylation that uses iodoarenes as coupling partners is reported (see scheme, EWG=electron‐withdrawing group). This process utilizes carboxylicacid units as temporary directinggroups that are cleaved during the reaction, leaving no trace in the resulting biaryl products.