• Proceedings of the Petrological Society of Korea Conference
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• 2009.05a
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• pp.32-34
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• 2009

• Journal of the Korean Chemical Society
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• v.28 no.6
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• pp.433-435
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• 1984

• Journal of the Korean Chemical Society
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• v.39 no.11
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• pp.884-886
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• 1995

• Journal of the Korean Chemical Society
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• v.39 no.8
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• pp.598-603
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• 1995

Kinetics for the reaction of para-substituted benzyl bromides with 3-picoline have been studied with the changes of substituent, pressure and temperature. The activation parameters and the Hammett ρ-values were determined from the values of rate constants. The results of these studies showed that the positive charge developed in the reaction center and bond cleavage was greater than bond formation. The reaction rate and the ability of charge transfer were increased with elevating pressure. The effect of pressure for the charge transfer was more enhanced at low temperatures.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.167-171
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• 1999

An investigation of the interaction of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pb(II) and Ag(I) with two N,N'-dibenzylated nitrogen-oxygen mixed donor macrocyclic ligands, has been carried out. Tle log K values for the respective complexes in 95% methanol have been determined potentiometrically. Both ligands have formed stable complex with only Cu(II) and Ag(I) ion. Transport measurements in a bulk liquid membrane system exhibited a very high selectivity of Ag(I) ion over the other metal ions used.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.340-348
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• 1982

The presence of 10 mole percent triphenyl borate accelerated dramatically the rate of reduction of structurally different sulfoxides with borane in tetrahydrofuran at room temperature, compared to the slow reduction with borane itself. Tetramethylene sulfoxide underwent complete reduction in 5 min and diethyl sulfoxide, dibenzyl sulfoxide and benzylphenyl sulfoxide were reduced quantitatively within 1h, whereas the reduction of diphenyl sulfoxide was rather slow, giving diphenyl sulfide in 90% yield in 24h. Boron trifluoride etherate and triethyl borate were less effective than triphenyl borate. A possible mechanism is presented.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.425-429
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• 2014

Pd on charcoal particles were prepared by wet impregnation to develop commercial catalyst for aerobic benzyl alcohol oxidation. Especially, one of room temperature ionic liquids, [Hmim][$PF_6$], was used as an effective solvent in the synthesis to improve the metal dispersion of the catalysts. Among the Pd/Charcoal with various Pd concentrations, 7.5 wt% catalyst showed the higher catalytic activity and stability. Moreover, Ag was used as a promoter with various ratios in catalyst preparation. Under identical reaction conditions, the catalyst with 9 : 1 of Pd and Ag weight ratios was most active due to higher metal dispersion.

• Journal of the Korean Chemical Society
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• v.34 no.3
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• pp.227-231
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• 1990

Kinetic studies on the nucleophilic reactions of p-substituted benzylnitrates with substituted anilines have been conductometically carried out in 50-100% $CH_3CN-CH_3OH$ mixtures. From the kinetic data, Hammett ${\rho}_C$ and ${\rho}_N$ values, Bronsted $\beta$ values, and solvatochromic coefficients were determined in order to examine the transition state variations caused by changes in substituents and solvent properties. It is concluded that the reaction proceeds via a synchronous $S_N2$ mechanism in which bond formation is more advanced than bond cleavage.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.453-459
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• 1992

3-Aryl-3-bromopropanoyl chloride in either ether or carbon tetrachloride reacted with 2 equiv. of hydroxylamine in the absence of trimethylsilyl chloride at ambient temperature to give directly 2,5-diarylisoxazolidin-3-ones in good yields. However, when 3-benzylhydroxylamine at $0^{\circ}C$, N-benzyl-3-bromo-3-phenylpropanohydroxamic acid (72%) and N-benzyl-C-phenylnitrone (12%) were obtained. On the contrary, 3-phenylisoxazolidin-5-one (41%) and 2-benzyl-S-phenyl-isoxzolidin-3-one (38%) were obtained when 3 equiv. of benzylhydroxylamine was used under the same conditions.

• Journal of the Korean Chemical Society
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• v.34 no.1
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• pp.19-28
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• 1990

The rate of chlorine-exchange reaction of antimony trichloride with benzyl, $\alpha$-phenyl ethyl and diphenyl methyl chlorides in nitrobenzene have been determined. The results indicate that the chlorine-exchange reaction follows second-order kinetics with respect to antimony trichloride and first-order kinetics with respect to organic chlorides. Rate = $k_3[SbCl_3]^2$ [Org-Cl] The rate constants of chlorine-exchange of antimony trichloride with organic chloride increase in the following order of the organic chlorides. Benzyl chloride < $\alpha$-phenyl ethyl chloride < diphenyl methyl chloride The mechanism of the chlorine-exchange reactions has been proposed.