• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.715-720
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• 2006

Metalhydrides such as $Cp(CO)_{2}(L)MH$ (L = t-butylisocyanide and 2,6-dimethylphenylisocyanide M = Mo and W) have been synthesized and used for ionic hydrogenation of the carbonyl groups in the presence of triflic acid. When these complexes have also used as catalyst precursors for hydrogenation of 3-pentanone under mild conditions ($23^{\circ}C,\;<4.1\;atm H_{2}$). The turnover rates were very slow, with the fastest initial rate of about 2 turnovers per 1 day for the [$Cp(CO)_{2}(ArNC)Mo][BA_{r}^{F}_{4}$] system.

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.249-253
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• 2014

Palladium on carbon catalysts for hexafluoropropylene hydrogenation were prepared using imidazolium hexafluorophosphate with various cation parts. The morphology of palladium was relatively affected by the cation parts of the ionic liquid. With increasing alkyl chains of the ionic liquid cation, the shape of palladium particle changed from spherical to cylindrical due to the effect of steric stabilization. After calcination at $500^{\circ}C$, all catalysts possessed the comparable crystal structure. Under the identical reaction conditions, the catalyst prepared using the ionic liquid with hexyl chain in cation parts showed the most effective reactivity.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1289-1292
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• 2005

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.412-415
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• 2013

Palladium on carbon powder was prepared using 1-hexyl-3-methylimidazolium tetrafluoroborate, one of room temperature ionic liquids. The synthesized particles were tested as a hexafluoropropylene hydrogenation catalyst. Moreover, the hydrogenation was performed under various reaction conditions to develop an optimum reaction process. The catalyst prepared by more than 3 wt% of palladium and the unity mole ratio of ionic liquid to palladium precursor showed higher catalytic activity. For reaction conditions, the complete hexafluoropropylene (HFP) conversion was achieved at these conditions; the volume flow ratio of hydrogen to HFP was higher than 1.25 and $GHSV_{HFP}$ was lower than 50000 mL/g-h.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.3105-3108
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• 2011

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.524-528
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• 1995

The reaction of [IrCl(cod)]2 with ppol ligand, Ph2PCH2CH2CH2P(Ph)CH2CH2CH=CH2, in ethanol gives an iridium complex, whose structure is converted from an ionic form, [Ir(cod)(ppol)]Cl·2C2H5OH (1),in polar solvents (ethanol, methanol and acetonitrile), to a molecular form, [IrCl(cod)(ppol)], in non-polar solvents (benzene and toluene). The cationic complexes, [Ir(cod)(ppol)]AsF6·1/2C2H5OH and [Ir(cod)(ppol)]PF6·1/2CH3CN, were prepared to compare with the ionic form by 31P NMR spectroscopy. When carbon monoxide is introduced to 1, cod is replaced by CO to give the 5-coordinated complex, [IrCl(CO)(ppol)]. Hydrogenation of 1-octene was not successful in the presence of 1. In order to verify the reason for 1 not behaving as a good catalyst for hydrogenation, electrophilic reactions with HCl, I2 and HBF4·etherate were performed, which yielded the oxidative addition product, [IrHCl2(ppol)], the substitution product, [IrI(cod)(ppol)], and another cationic product, [Ir(cod)(ppol)]BF4, respectively. Thus, the iridium complex is not sufficiently basic to activate hydrogen atoms or the olefin of the ppol ligand.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4069-4073
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• 2012

Metallacyclodimeric complexes of $[(Me_4en)Pd(L)]_2(ClO_4)_4$ ($Me_4en$ = N,N,N',N'-tetramethylethylenediamine; L = dimethylbis(4-pyridyl)silane (dmps), methylvinylbis(4-pyridyl)silane (mvps)) have been synthesized, and their structures have been characterized by X-ray single crystallography. The skeletal structures consist of one 20-membered metallamacrocycle, two 5-membered metallacycles, and four pyridyl groups. The local geometry around the palladium(II) ion approximates to a typical square planar arrangement with four nitrogen donors. Delicate difference in catalytic effects on hydrogenation was investigated based on the structure of catalyst and substrates.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2195-2200
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• 2010

The reaction of $PdCl_2$ dispersed in tetra-n-butylammonium bromide with tributyl amine at $120^{\circ}C$ under argon leads to stable isolable nanometric particles. X-ray diffraction analysis of the material indicated that it is constituted of Pd(0). Transmission electron microscopy analysis of the particles dispersed in acetone shows the mean particle size distribution ($4{\pm}1\;nm$). The isolated palladium nanoparticles can be dispersed in an ionic liquid or in methanol or used in solventless condition for selective hydrogenation of 2-hexyne under mild reaction conditions(0.2 MPa and $20^{\circ}C$). The commercial variety of the Lindlar catalyst was also studied for comparative investigations.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.531-542
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• 2012

The thesis covers the trend of research on bio-based polyurethane which is made from polyols derived mainly from plant oils and isocyanates. Castor oil is a triglyceride of ricinoleic acid containing hydroxyl group. Hydroxylation is done on the unsaturated bonds of the oils by the reactions of epoxidation/ring opening, hydroformylation/hydrogenation, ozonolysis/hydrogenation, and thiol-ene reaction. Polyols from hyperbranch, primary alcohol, polysaccharide have been studied to control the reactivity of the polyol and morphology of the microdomains. Besides, researches cover biodegradable polylactic acid polyol for medical use, fatty acid dimer polyol for the prevention of hydrolysis, and polyol with ionic group for water-borne polyurethane. Bio-based polyurethanes are being used in flexible and rigid foams, coatings, sealants, and elastomers.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1127-1130
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• 2013

Formation of the monodisperse submicrospheres consisting of ionic palladium(II) complexes, $[(Me_4en)Pd(L)]_2(X)_4$($Me_4en$ = N,N,N',N'-tetramethylethylenediamine; L = bis(4-(4-pyridylcarboxyl)phenyl)methane; $X^-=BF_4{^-}$ and $ClO_4{^-}$), has been carried out without any templates or additives. The submicrospheres were coated with silicates, and then calcined in air at $550^{\circ}C$ for 1 h, to efficiently form hollow-spherical $SiO_2$ submicro-reactors dotted with palladium(0) nanoparticles (PdNPs). That is, the submicrospheres act as both a template and a source of the palladium metal nanoparticles. The submicro-reactors containing nano-catalysts have been characterized by means of SEM, TEM, and XPS. Notably, the reactors were proved to be very effective for Suzuki-Miyaura cross-coupling and hydrogenation reactions.