113538-80-0Relevant articles and documents
N-heterocyclic carbene coordinated heterogeneous Pd nanoparticles as catalysts for suzuki-miyaura coupling
Min, Hyemin,Miyamura, Hiroyuki,Kobayashi, Shu
supporting information, p. 837 - 839 (2016/07/16)
Palladium nanoparticle (Pd NP) catalysts immobilized in a polymer with an N-heterocyclic carbene (NHC) moiety (PICBNHC-Pd) have been developed, wherein the NHC moiety plays dual roles as a crosslinker and a ligand to activate the Pd NPs. The presence of both Pd NPs and NHC was confirmed by STEM/EDS and SR-MAS NMR analyses, respectively. This PICB-NHC-Pd catalyst showed excellent activity in the Suzuki-Miyaura coupling reaction without leaching of Pd. Excellent results were obtained in gram-scale synthesis, and catalyst recovery/reuse experiments were completed without loss of catalyst activity.
Preparation of polymer incarcerated gold nanocluster catalysts (PI-Au) and their application to aerobic oxidation reactions of boronic acids, alcohols, and silyl enol ethers
Miyamura, Hiroyuki,Yasukawa, Tomohiro,Kobayashi, Shu
, p. 6039 - 6049 (2015/03/30)
Heterogeneous gold nanocluster catalysts immobilized by the method known as polymer incarceration were prepared. Polystyrene-derived polymers with epoxide and alcohol moieties, which could be cross-linked under heating conditions, were employed as supports for their preparation. Cationic gold salts were reduced in a solution of NaBH4 and the polymers. Poor solvents for the polymers were added, and the polymers were precipitated and encapsulated gold nanoclusters with weak but multiple interactions between a gold nanocluster surface and the π electrons of benzene rings. The polymer capsules were heated under neat conditions to afford heterogeneous gold nanocluster catalysts; namely, polymer-incarcerated gold nanoclusters. The catalysts thus prepared could be applied to the aerobic oxidation of phenyl boronic acids, alcohols, and silyl enol ethers. We found that the choice of polymers, good and poor solvents for the polymers, metal loadings, heating conditions for cross-linking, and final activation were all crucial for obtaining high-activity catalysts.
Copolymer-incarcerated nickel nanoparticles with N-heterocyclic carbene precursors as active cross-linking agents for Corriu-Kumada-Tamao reaction
Soule, Jean-Francois,Miyamura, Hiroyuki,Kobayashi, Shu
supporting information, p. 10602 - 10605 (2013/08/23)
We have developed heterogeneous polymer-incarcerated nickel nanoparticles (NPs), which catalyze cross-coupling reactions. The matrix structure of these catalysts incorporates both N-heterocyclic carbenes (NHCs) as ligands and Ni-NPs, thanks to a new design of cross-linking agents in polymer supports. These embedded NHCs were detected by field gradient swollen-resin magic angle spinning NMR analysis. They were successfully applied to Corriu-Kumada-Tamao reactions with a broad substrate scope including functional group tolerance, and the catalyst could be recovered and reused several times without loss of activity.