Rh compounds including Rh nanoparticles are among the most active catalysts for many reactions.Catalytically very reactive small Rh nanoparticles have been generated upon reduction of aqueous RhCl_(3) by cobaltocene,c...Rh compounds including Rh nanoparticles are among the most active catalysts for many reactions.Catalytically very reactive small Rh nanoparticles have been generated upon reduction of aqueous RhCl_(3) by cobaltocene,characterized,and shown to be very efficient for the test nitrophenol reduction(compared to other metal NPs),generation of hydrogen from ammonia borane hydrolysis,transfer hydrogenation,and benzene hydrogenation.This useful concept of cobalticinium chloride-stabilized NP catalysts could potentially be efficiently applicable to a variety of other aqueous catalytic systems.展开更多
The Ullmann coupling reaction of aromatic halides is the most challenging C–C coupling reaction.Both MOF-based and MOF-deriffed types of catalysts haffe recently proffided useful nanocatalysts for a ffariety of react...The Ullmann coupling reaction of aromatic halides is the most challenging C–C coupling reaction.Both MOF-based and MOF-deriffed types of catalysts haffe recently proffided useful nanocatalysts for a ffariety of reactions,but they haffe rarely been compared.Herein,the Ullmann-type aryl iodide homocoupling is effciently catalyzed by gold and palladium nanoparticles(NPs)loaded on ZIF-8 before(ZIF-8-based nanocatalyst:M@ZIF-8)and after calcination(ZIF-8-deriffed catalyst:M@CN).The nanocatalysts M@ZIF-8(M=Pd,Au)are found to be more effcient than the catalysts M@CN.Pd@ZIF-8 exhibits better perform ances than those of Au@ZIF-8 for a series of aryl iodides,but in the case of 4-nitro-iodobenzene,deshy droiodination was obserffed besides the coupling product.Mechanisms are proposed and discussed for both Au(0)and Pd(0)nanocatalysts.展开更多
Dendrimers have already been successfully used in nanoparticle(NP)catalysis for many years,particularly for Pd NP protection towards carbon-carbon coupling reactions.In this paper,assemblies between Pd nanoparticles a...Dendrimers have already been successfully used in nanoparticle(NP)catalysis for many years,particularly for Pd NP protection towards carbon-carbon coupling reactions.In this paper,assemblies between Pd nanoparticles and two generations of“click”dendrimers,with 27(dendrimer-1)and 81(dendrimer-2)triethylene glycol(TEG)termini,respectively,are examined for catalytic peroxidase-like oxidative activity.This catalysis is investigated with o-phenylenediamine(OPD)and H_(2)O_(2)as the substrates in water,displaying different colours.展开更多
基金China Scholarship Council of the People’s Republic of China(PhD grant to W.W.)。
文摘Rh compounds including Rh nanoparticles are among the most active catalysts for many reactions.Catalytically very reactive small Rh nanoparticles have been generated upon reduction of aqueous RhCl_(3) by cobaltocene,characterized,and shown to be very efficient for the test nitrophenol reduction(compared to other metal NPs),generation of hydrogen from ammonia borane hydrolysis,transfer hydrogenation,and benzene hydrogenation.This useful concept of cobalticinium chloride-stabilized NP catalysts could potentially be efficiently applicable to a variety of other aqueous catalytic systems.
基金the China Scholarship Council of the People’s Republic of China(PhD grant to W.W.),the National Science Center of Poland under the program OPUS(E.C.and S.M.:2019/33/B/ST5/01495)the University of Bordeaux,the Centre National de la Recherche Scientifique(CNRS)and CIC biomaGUNE is gratefully acknowledged.
文摘The Ullmann coupling reaction of aromatic halides is the most challenging C–C coupling reaction.Both MOF-based and MOF-deriffed types of catalysts haffe recently proffided useful nanocatalysts for a ffariety of reactions,but they haffe rarely been compared.Herein,the Ullmann-type aryl iodide homocoupling is effciently catalyzed by gold and palladium nanoparticles(NPs)loaded on ZIF-8 before(ZIF-8-based nanocatalyst:M@ZIF-8)and after calcination(ZIF-8-deriffed catalyst:M@CN).The nanocatalysts M@ZIF-8(M=Pd,Au)are found to be more effcient than the catalysts M@CN.Pd@ZIF-8 exhibits better perform ances than those of Au@ZIF-8 for a series of aryl iodides,but in the case of 4-nitro-iodobenzene,deshy droiodination was obserffed besides the coupling product.Mechanisms are proposed and discussed for both Au(0)and Pd(0)nanocatalysts.
基金support from the China Scholarship Council,CSC(YL),the CAPES/Brazil,Process:88881.337360/2019-01CNPq/FAPEMIG,agreement recorded in SICONV:793988/2013(RPL),the MAT2017-88752-R Retos Project from the Ministerio de Economía,Industria y Competitividad,gobierno de España(SM),the Universities of Bordeaux and Rennes 1 and the Centre National de la Recherche Scientifique(CNRS)is gratefully acknowledged.
文摘Dendrimers have already been successfully used in nanoparticle(NP)catalysis for many years,particularly for Pd NP protection towards carbon-carbon coupling reactions.In this paper,assemblies between Pd nanoparticles and two generations of“click”dendrimers,with 27(dendrimer-1)and 81(dendrimer-2)triethylene glycol(TEG)termini,respectively,are examined for catalytic peroxidase-like oxidative activity.This catalysis is investigated with o-phenylenediamine(OPD)and H_(2)O_(2)as the substrates in water,displaying different colours.
