• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.657-661
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• 1989

Symmetrical divinyl ketone or divinyl ${\alpha}$-diketone was synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylmercuric chlorides with carbon monoxide. In order to find out optimum synthetic reaction conditions, we examined the effect of catalysts, bases, solvents and reaction temperature when (E)-styrylmercuric chloride was used as a typical starting material. The best yield of divinyl ${\alpha}$-diketone was obtained in the reaction using 10 mol% of dichlorobis(triphenyl phosphine)palladium (II) as a catalyst, an equivalent of pyridine as a base, 10 mol% of iodine and acetonitrile at 50${\circ}$C under 10 atmospheric pressure of carbon monoxide. The yield of divinyl ${\alpha}$-diketone was decreased under atmospheric pressure of carbon monoxide.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.522-529
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• 1989

Symmetrical divinyl ketones and divinyl ${\alpha}$-diketones were synthesized in moderately good yields through palladium catalyzed carbonylative homocoupling reaction of vinylic halides. Divinyl ${\alpha}$-diketones were obtained in the highest yield in the presence of 10 atm of carbon monoxide, using 2 mol% ligand added to palladium(II) acetate as catalyst and three equivalents of tributylamine as base in polar solvent at $100^{\circ}C$. Divinyl ketones were synthesized mainly under atmospheric pressure of carbon monoxide. The reaction was also proceeded to several other vinylic halides under the above reaction condition. Thus, divinyl ketones and divinyl ${\alpha}$-diketones were synthesized selectively as expected.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.3
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• pp.264-269
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• 2016

A simple dry chemical approach was developed in order to load palladium (Pd) as a promoter on Pt/gas diffusion electrode (GDE) for polymer electrolyte membrane fuel cell (PEMFC). Palladium(II) bis (acetylacetonate), $Pd(acac)_2$ was sublimed, penetrated into Pt/GDE and then reduced to Pd nanoparticles simultaneously without any reducing agent and any solvent in a glass reactor of $N_2$ atmosphere at $180^{\circ}C$ for 3, 5 and 15 min. Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.3
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• pp.270-275
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• 2016

A simple solid state incorporation method was employed in order to incorporate Pd nanocatalyst into a Nafion film for polymer electrolyte membrane fuel cell (PEMFC) via the reduction of palladium (II) bis (acetylacetonate), $Pd(acac)_2$. It was sublimed, penetrated into Nafion film and then reduced to Pd nanoparticles simultaneously in a glass reactor of N2 atmosphere at $180^{\circ}C$ for 1, 3 and 5 min. This reaction was took place without any reducing agent and any solvent. The morphology of the Pd nanoparticles was observed by transmission electron microscopy (TEM), and Pd distribution was analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). And 23% modification of tensile strength of Pd/Nafion composite film was measured by universal testing machine and I-V curve was estimated by using a unit cell with $5{\times}5cm^2$ active area.

• Macromolecular Research
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• v.15 no.2
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• pp.185-190
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• 2007

Poly(norbornene dimethyl dicarboxylate)s, (PNDMD)s, were prepared by addition polymerization with palladium(II) catalyst from pure exo-monomers, and their structure and properties were compared with those of poly(norbornene dicarboxylic acid dialkyl ester)s, (PNDADA)s. Both polymer series exhibited good solubility in general organic solvents and excellent thermal stability up to $330^{\circ}C$. Wide-angle X-ray scattering (WAXS) study indicated the presence of nano-scale layer-like order in amorphous PNDADAs, while PNDMDs showed random amorphous structure. The glass transition temperatures and dielectric constants of solid polymers were found to decrease as the alkyl side-chain length increases for both polymer series. However, PNDMDs showed lower glass transition temperatures and higher dielectric constants, as compared with those of PNDADAs containing the same alkyl substituents. This difference, caused by the higher side-group mobility of PNDMDs, may be closely related to the nano-scale order in amorphous PNDADAs and its absence in PNDMDs.