Oberholzer Miriam, Frech Christian M
Institute of Inorganic Chemistry, University of Zürich.
Institute of Chemistry & Biological Chemistry, Zürich University of Applied Sciences;
J Vis Exp. 2014 Mar 20(85):51444. doi: 10.3791/51444.
Dichloro-bis(aminophosphine) complexes of palladium with the general formula of [(P{(NC5H10)3-n(C6H11)n})2Pd(Cl)2] (where n = 0-2), belong to a new family of easy accessible, very cheap, and air stable, but highly active and universally applicable C-C cross-coupling catalysts with an excellent functional group tolerance. Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium [(P(NC5H10)3)2Pd(Cl)2] (1), the least stable complex within this series towards protons; e.g. in the form of water, allows an eased nanoparticle formation and hence, proved to be the most active Heck catalyst within this series at 100 °C and is a very rare example of an effective and versatile catalyst system that efficiently operates under mild reaction conditions. Rapid and complete catalyst degradation under work-up conditions into phosphonates, piperidinium salts and other, palladium-containing decomposition products assure an easy separation of the coupling products from catalyst and ligands. The facile, cheap, and rapid synthesis of 1,1',1"-(phosphinetriyl)tripiperidine and 1 respectively, the simple and convenient use as well as its excellent catalytic performance in the Heck reaction at 100 °C make 1 to one of the most attractive and greenest Heck catalysts available. We provide here the visualized protocols for the ligand and catalyst syntheses as well as the reaction protocol for Heck reactions performed at 10 mmol scale at 100 °C and show that this catalyst is suitable for its use in organic syntheses.
通式为[(P{(NC5H10)3-n(C6H11)n})2Pd(Cl)2](其中n = 0 - 2)的钯二氯双(氨基膦)配合物,属于一类新型的易于获得、价格非常便宜且对空气稳定,但活性高且普遍适用的碳 - 碳交叉偶联催化剂,具有出色的官能团耐受性。二氯{双[1,1',1'' - (膦亚基)三哌啶]}钯[(P(NC5H10)3)2Pd(Cl)2](1),是该系列中对质子最不稳定的配合物;例如以水的形式,它能使纳米颗粒更容易形成,因此被证明是该系列中在100℃时最具活性的Heck催化剂,并且是在温和反应条件下有效运行的高效通用催化剂体系的非常罕见的例子。在后处理条件下催化剂迅速且完全降解为膦酸盐、哌啶鎓盐和其他含钯分解产物,确保了偶联产物与催化剂和配体的轻松分离。1,1',1'' - (膦亚基)三哌啶和1分别易于、廉价且快速地合成,使用简单方便,以及其在100℃的Heck反应中出色的催化性能,使1成为最具吸引力和最绿色的Heck催化剂之一。我们在此提供配体和催化剂合成的可视化方案以及在100℃下以10 mmol规模进行的Heck反应的反应方案,并表明该催化剂适用于有机合成。