Immobilized Catalysts for Iridium-Catalyzed Allylic Amination: Rate Enhancement by Immobilization
作者:Chandi C. Malakar、Günter Helmchen
DOI:10.1002/chem.201500382
日期:2015.5.4
The first immobilizedcatalyst for Ir‐catalyzed asymmetric allylicaminations is described. The catalyst is a cationic (π‐allyl)Ir complex bound by cation exchange to an anionic silica gel support. Preparation of the catalyst is facile, and the supported catalyst displayed considerably enhanced activity compared with the parent homogeneous catalyst. Up to 43 consecutive amination runs were possible
Regio- and Enantioselective <i>N</i>-Allylations of Imidazole, Benzimidazole, and Purine Heterocycles Catalyzed by Single-Component Metallacyclic Iridium Complexes
作者:Levi M. Stanley、John F. Hartwig
DOI:10.1021/ja902243s
日期:2009.7.1
Kinetic studies on the allylation of benzimidazole catalyzed by metallacyclic iridium-phosphoramidite complexes, in combination with studies on the deactivation of these catalysts in the presence of heterocyclic nucleophiles, provide insight into the effects of the structures of the phosphoramidite ligands on the stability of the metallacyclic catalysts. The data obtained from these studies have led to