Transition metal nanoparticles stabilized by ammonium salts of hyperbranched polystyrene: effect of metals on catalysis of the biphasic hydrogenation of alkenes and arenes

Abstract

a b s t r a c tHyperbranched polystyrene bearing ammonium salts (HPS-NR 3 þ Cl À ) behaves as an excellent stabilizer of ruthenium, rhodium, iridium, palladium, and platinum nanoparticles from 1 to 3 nm in size uniformly dispersed in the polymer matrix. The catalytic performance of the resulting metal-polymer composites, M@HPS-NR 3 þ Cl À , is dependent on the metal. This dependence was investigated by assessing the hydrogenation of alkenes and arenes. The utility of M@HPS-NR 3 þ Cl À as reusable catalysts in aqueous/organic biphasic systems was demonstrated by examining the catalysis of the hydrogenation of aromatic compounds containing various functional groups by Ru@HPS-NR 3 þ Cl À .

Effect of the Crystallographic Phase of Ruthenium Nanosponges on Arene and Substituted‐Arene Hydrogenation Activity

“…Among the many homogeneous and heterogeneous ruthenium catalysts, homogeneous small‐molecule‐based catalysts, the true nature of which (homogeneous or heterogeneous colloidal particles) is still under scrutiny, show poor activity . On the other hand, surfactant‐ and ionic‐liquid‐stabilized ruthenium nanoparticles and supported (MOFs, polymers, dendrimers, metal oxides) ruthenium nanoparticles were found to be catalytically active for arene hydrogenation reactions . Although, several heterogeneous ruthenium nanostructures were reported for hydrogenation of derivatives of benzene, yet the influence of the crystallographic phase of ruthenium on hydrogenation of arenes has not been explored.…”

Hyperbranched Polysiloxanes Based on Polyhedral Oligomeric Silsesquioxane Cages with Ultra-High Molecular Weight and Structural Tuneability

“…Dendritic polymers, either hyperbranched ones or dendrimers, have been proved useful in stabilizing transition nanoparticles [ 50 , 51 , 52 , 53 ], which are of high importance in organic catalysis. The presence of rigid POSS subunits are helpful for forming internal porosity to host such nanoparticle, especially with the assistance of polar phosphonate groups introduced in polymer 3 .…”

“…Refluxing polymer 2 with triethylphosphite resulted in around 59% incorporation of phosphonate groups (as shown in Figure 5, detailed analysis in Figure S7), and the obtained polymer 3 dissolves in various solvents very well, but still not in methanol, probably because the polar phosphonate groups are buried within the polymer, preventing effective interaction with the methanol solvent molecules. Dendritic polymers, either hyperbranched ones or dendrimers, have been proved useful in stabilizing transition nanoparticles [50][51][52][53], which are of high importance in organic catalysis. The presence of rigid POSS subunits are helpful for forming internal porosity to host such nanoparticle, especially with the assistance of polar phosphonate groups introduced in polymer 3.…”

Catalysis to discriminate single atoms from subnanometric ruthenium particles in ultra-high loading catalysts

“…74 Colloidal metallic NP (Rh, Ru, Pt), although less active (TOF = 160-320 h -1 ) are also efficient catalysts for this reaction under relatively mild conditions (room temperature to 75°C, 1-10 bar of H 2 ). 76,77 As far as supported catalysts are concerned (Rh, Co), much lower activities were reported (TOF = 2-10 h -1 ) under slightly harsher operating conditions (25 to 150°C, 5-40 bar). 78,79 Please do not adjust margins Please do not adjust margins reaction with the T 50 M 50 -Ru@C 60 catalyst is completed within 2 h. The calculated TOF at 20% conversion 470 h -1 is to the best of our knowledge the higher ever reported for supported metallic NP.…”