SPION-A-Pd(EDTA) (superparamagnetic iron oxide nanoparticles-A-ethylendiamine tetraacetic acid) as a robust nanocatalyst for Buchwald-Hartwig C-N Coupling Reaction

Abstract

During thelast20-30 years, palladium-catalyzed reactions have witnessed tremendous advances in the industrial and organic reactions such as hydrogenation, coupling, cyanation and amination. Despite the wide utility of Pd-catalysts in these reactions, they suffer from a number of drawbacks such as recovery, reuse of catalyst and remain as a contaminant in the products at the end of the reaction.<br /> A powerful and convenient reaction procedure for the C-N coupling reaction (the Buchwld-Hartwig reaction), yielding products of N-arylanilines and N-arylamines in conventional heating has been reported. The protocol utilized an high stable Pd(EDTA)^2- salt by counter cation of N-methylimidazolium bounded to 1,3,5-triazine-tethered SPIONs (superparamagnetic iron oxide nanoparticles). The reaction products were produced under conventional heating at extremely low catalyst loading (as low as 0.003 mol% Pd).Finally, we also examined the reusability of the catalyst. It was found that the catalyst could be recovered by external magnetic field and be reused for five times without obvious loss in catalytic activity.