A biocompatible hybrid system composed of graphene oxide (GO), chitosan (CS) and ionic liquid decorated cyclodextrin nanosponge (CDNS-IL) is synthesized and applied for the immobilization of Pd and Fe3O4 nanoparticles to furnish a magnetic catalyst, Fe3O4/Pd@Hybrid. The justification for designing this hybrid system was benefiting from the capability of CDNS for formation of inclusion complex with substrates and acting as phase transfer agent. Moreover, IL itself could exert catalytic activity and improve anchoring Pd, while magnetic nanoparticles could render the catalyst easily separable. Moreover, the functional groups on CS could contribute to Pd anchoring. The catalytic activity of Fe3O4/Pd@Hybrid for promoting hydrogenation of nitro arenes and two coupling reactions in aqueous media was investigated. The results established that the catalyst could efficiently promote all the reactions under mild reaction condition. The investigation of the catalyst recyclability confirmed that the catalyst could be recycled for three reaction runs.

Carbon nanotubes and cyclodextrin nanosponge were hybridized and used as a support for embedding Pd(0) nanoparticles and developing a novel and heterogeneous catalyst, Pd@CDNS-CNT, for promoting ligand and copper-free Sonogashira and Heck coupling reactions in aqueous media and mild reaction condition. Cyclodextrin nanosponge could contribute to catalysis through encapsulating the reagents and transferring them in the vicinity of Pd nanoparticles. The results established that the catalytic activity of Pd@CDNS-CNT was superior to those of Pd@CNT, Pd@CDNS and Pd@CNT + CDNS, indicating the synergism between the components of the hybrid system. Notably, various aryl halides including aryl iodide, bromide and chloride were useful substrates for the coupling reactions and affording the corresponding products in high to excellent yields in short reaction times. Moreover, the catalyst was recyclable up to six reaction runs with negligible Pd leaching.

A novel hybrid system composed of sepiolite clay and cyclodextrin nanosponge (CDNS) was prepared via reaction of Cl‐functionalized sepiolite with amine‐functionalized CDNS. CDNS–sepiolite was then applied for immobilization of Pd(0) nanoparticles. The resulting hybrid system, Pd@CDNS‐sepiolite, was characterized using various techniques and successfully used as an efficient and heterogeneous catalyst for ligand‐ and copper‐free Sonogashira and Heck coupling reactions under mild reaction conditions. Recycling experiments confirmed that Pd@CDNS‐sepiolite was recyclable and could be used for several consecutive reaction runs with slight Pd leaching and loss of catalytic activity.

For the first time a novel magnetic catalyst was prepared through hybridization of functionalized cyclodextrin nanosponges and octakis(3chloropropyl)octasilsesquioxane followed by incorporation of Pd and magnetic nanoparticles. The resulting composite, was utilized as an efficient heterogeneous catalyst for promoting Sonogashira and Heck reactions in the absence of any ligand and co-catalyst under mild reaction condition. Comparison of the catalytic activities of the control catalysts and the catalyst confirmed that cyclodextrin nanosponges was more efficient support that cyclodextrin. Moreover, the hybrid catalyst showed superior catalytic activity compared to those obtained from the individual components, indicating the contribution of both hybrid components to the catalysis. Furthermore, it was

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