Palladium Nanoparticles Supported on Poly(N‐vinyl‐ imidazole‐co‐N‐vinylcaprolactam) as an Effective Recyclable Catalyst for the Suzuki Reaction

Abstract

A recyclable and effective polymer‐immobilized ligandless palladium catalyst for the Suzuki reaction has been investigated. Palladium nanoparticles are formed in situ and stabilized by poly(N‐vinylimidazole‐co‐N‐vinylcaprolactam). A series of aryl bromides have been studied in the reaction with phenylboronic acid under mild conditions with water–alcohol systems as a solvent that complies with “Green Chemistry” demands. The catalyst can be recycled eight times without appreciable loss in activity and a low degree of palladium leaching. Kinetic studies reveal unusual behavior of the reaction; this can be explained on the basis of the observation of changes to the sizes of the particles during recycling, as determined by TEM results. The suggested mechanism of the reaction is in accordance with the concept of the role of leaching in the process.

Long-Range Olefin Isomerization Catalyzed by Palladium(0) Nanoparticles

“…The formation of Pd(0) nanoparticles by the in situ reduction of Pd(II) with ethylene or vinyl compounds and their applications have been reported. 19 The SEM images also revealed changes in the morphology of the palladium, which gradually transformed from micrometer-scaled metal salts into nanometer-sized metal rods. The average size of the generated Pd(0) nanoparticles is 656 ± 176 nm, and a plot of their size distribution is shown in the Supporting Information.…”

Physicochemical aspects of inorganic nanoparticles stabilized in N-vinyl caprolactam based microgels for various applications

“…Pd nanoparticles stabilized polymer microgels are widely used as catalysts for Suzuki coupling reactions but only few reports are available on stabilization of Pd nanoparticles in VCL based polymer microgels for such kind of organic transformation. 57,86,87 Contin et al 57 reported catalytic ability of Pdclay-P(VCL-AAEM) hybrid microgels towards Suzuki coupling reactions using organic base, trimethylamine (NEt 3 ) in waterethanol (EtOH/H 2 O) medium at 80 C according to Scheme 1.…”

Green Synthesis of Stable Nanocomposites Containing Copper Nanoparticles Incorporated in Poly-N-vinylimidazole

“…This offers wide opportunities for polymer modification. Such polymers effectively sorb metal ions to afford the coordination complexes possessing catalytic activity [ 35 , 36 ]. The most important feature of N-vinylimidazole polymers is solubility in water, due to which they are widely used in medicine.…”