Metallodendritic Grafted Core–Shell γ‐Fe₂O₃ Nanoparticles Used as Recoverable Catalysts in Suzuki CC Coupling Reactions

Abstract

The use of dendritic structures for the grafting of core-shell γ-Fe(2)O(3)/polymer 300 nm superparamagnetic nanoparticles (MNPs) has been performed with four metallodendrons that were functionalized with diphosphinopalladium complexes. The catalytic performance of these nanocatalysts was optimized for the Suzuki C-C cross-coupling reaction. These results demonstrated the importance of optimizing the catalytic efficiency of grafted MNPs by optimizing the dendritic structures and the nature of the peripheral phosphine ligands. All of these nanocatalysts showed remarkable reactivity towards bromoarenes and they were recovered and efficiently reused by magnetic separation with almost no loss of reactivity, even after 25 cycles.

Dendritic maleimide functionalization of core–shell (γ-Fe2O3/polymer) nanoparticles for efficient bio-immobilization

“…Therefore, in this work we aimed to ensure a high number of functional groups at the MNP surface by its functionalization with dendritic coupling agent. The efficiency of this approach was demonstrated in our previous results, which showed an increase of the surface functionalization [13][14][15] together with a dendritic effect on the intrinsic physico-chemical properties of the materials. 16 In this study, the maleimide functional group was chosen for its biocompatibility and for its high selectivity towards thiol group of cysteine residue, naturally present or articially introduced in biomolecules.…”

Pyrene‐Tagged Dendritic Catalysts Noncovalently Grafted onto Magnetic Co/C Nanoparticles: An Efficient and Recyclable System for Drug Synthesis

“…Covalently immobilized dendronized catalysts, which possess an anchoring site and branches terminating with active sites, represent another promising strategy for recoverable catalysts, as they were shown to afford enhanced surface functionalization [8] and better catalytic activity than corresponding monomeric catalysts. [8a,d] Combining both strategies, we planned to graft pyrene-tagged dendritic Pd-phosphine catalysts onto Co/C MNPs by p-p stacking, and to evaluate the activity and recyclability of the resulting composites in Suzuki reactions.…”

Obtaining a novel crystalline/amorphous core/shell structure in barium titanate nanocrystals by an innovative one-step approach

“…The results show that very fine BaTiO 3 core/shell nanocrystals (<11 nm) free from any by-products such as BaTi 2 O 5 and BaCO 3 are synthesized at 323 K (50 °C). As the great advance made by this work, our method of synthesis is able to obtain high-quality homogenous carbonate-free BTO nanocrystals at a low temperature of 323 K (50 °C).Core-shell nanostructures have recently received much attention for their enhanced properties and performances [24][25][26][27]. 3 significantly change its dielectric behavior and turn dielectric nature of BTO to semiconducting one [21].…”

“…Core-shell nanostructures have recently received much attention for their enhanced properties and performances [24][25][26][27]. Moreover, the core-shell structures are normally chosen believing that these can cause a better coupling between the two phases.…”