Palladium methylacrylate

Liu et al. prepared palladium nanoparticles in water-dispersible poly(acrylic acid) (PAA)-lined channels of diblock copolymer microspheres [47]. The diblock microspheres (mean diameter 0.5 pm) were prepared using an oil-in-water emulsion process. The diblock used was poly(t-butylacrylate)-Wock-poly(2-cinna-moyloxyethyl) methacrylate (PtBA-b-PCEMA). Synthesis of the nanoparticles inside the PAA-lined channels of the microspheres was achieved using hydrazine for the reduction of PdCl2, and the nanoparticle formation was confirmed from TEM analysis and electron diffraction study (Fig. 9.1). The Pd-loaded microspheres catalyzed the hydrogenation of methylacrylate to methyl-propionate. The catalytic reactions were carried out in methanol as solvent under dihydro-... 

In the second series of experiments, O. Nuyken et al. investigated the Heck reaction of iodobenzene with styrene as a model for the numerous palladium-catalyzed coupling reactions (Scheme 6.6) [54]. In the literature only a few Heck coupling reactions of hydrophobic substrates in aqueous solution are known. The most detailed study has been performed by Jeffery et al. on the model reaction of iodobenzene with methylacrylate in the presence of tetrabutylammonia salts. Product yield was at least 95% after 2 h reaction time at 50 °C in pure aqueous solution [55], however more... 

Palladium catalysts are used for the copolymerization of ethylene and methylacrylate (281). The copolymers contain both alkyl and ester side chains. 

An immobilized version of a Heck reaction catalyzed by Pd nanoparticles has been very recently described by Kaiimi and Enders [289]. The nanoparticles were obtained as a result of the covalent anchoring of a N-heterocyclic carbene palladium/ionic liquid matrix on a silica surfece and their nature was confirmed by TEM coupled with EDX analysis. The catalyst showed high thermal stability (up to 280 °C) and could be recycled four times for the reaction of bromobenzene with methylacrylate achieving a total turnover number of 36600. After carrying out a hot filtration process, the authors could not detect any Pd in the filtrate. The filtrate also showed no further reaction progress. Erom these findings the authors concluded that the reaction was, in their case, indeed catalyzed by the heterogeneous Pd particles and not from monomolecular Pd-complexes leached from the sur ce. 

Palladium can also be supported on different metal oxides. In 1995, Augustine and coworkers used Pd/Si02 as catalyst for the reaction of aryl chlorides and alkylenolethers [80], The group of Aral studied the reaction of iodobenzene and methylacrylate in the presence of several bases. They presented evidence that leached soluble Pd species were the tme catalysts [81],... 

The reduction of palladium(ii) complexes (often with Li2(COT)) in the absence of other ligands is an experimentally demanding but convenient and fairly general method for the preparation of palladium(O) complexes with olefins, and was used to prepare a complex with methylacrylate (MA), Pd(dppf)( 7 -MA), from PdCl2(dppf), Li2(COT), and MA. ... 

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