A Novel Heterogeneous Pd -Immobilized Nano Catalyst Composed of Cyclodextrin Nanosponges and CNTs for Catalyzing Ligand and Copper Free C-C Coupling reactions

A hybrid of cyclodextrin nanosponge (CDNS) and CNT was used as a support to embed Pd nanoparticles. The obtained catalyst, Pd@CDNS-CNT could promote ligand and copper-free Sonogashira and Heck coupling reactions under mild reaction condition and aqueous media. Various ligand and copper free C-C coupling reactions with different kinds of aryl halides such as aryl iodide, bromide and chloride catalyzed by the above-mentioned catalyst resulted in high to excellent yields of the corresponding products in short reaction times. The role of CDNS in encapsulating of reagents and transferring them in the vicinity of Pd nanoparticles is significant for catalytic activity. The result of this study proved that the catalytic activity of Pd@CDNS- CNT was more than Pd@CNT, Pd@CDNS and Pd@CNT+CDNS due to the synergetic effect between the components of the hybrid system. In addition, the catalyst exhibited negligible Pd leaching after several reaction runs.

Keywords:

Carbon nanotubes , Cyclodextrin nanosponge , Pd nanoparticles , C-C coupling reactions