• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1272-1287
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• 2002

Sonochemical Reformatsky reaction of aldehydes or ketones with ethyl bromoacetate in the presence of indium afforded $\beta-hydroxyesters$ in good to excellent yields under mild conditions. 2- or 3-Hydroxybenzaldehyde that contains an acidic hydrogen r eacted with ethyl bromoacetate to provide the desired compounds with the same efficiency. In the case of ethyl 2-bromopropanoate and ethyl 2-bromo-2-methylpropanoate, the desired products were obtained in good yields. Reaction of aldehyde with indium reagent in the presence of ketone group proceeded chemoselectively.

• Bulletin of the Korean Chemical Society
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• v.1 no.1
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• pp.23-26
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• 1980

Direct photoisomerizations of benzalpyrrolinones yield the corresponding E-isomers via a singlet state, since no effect of oxygen on the reaction rates was observed. The Z-oxodipyrromethene was photoisomerized to the E-isomer in a degassed system. In an aerobic system the oxodipyrromethene 3 was photoisomerized at the early stage of the reaction and photooxygenated slowly at latter stage of the reaction. For bilirubin, other (possibly Z ${\to}$ E) than self-sensitizing $^1O_2$ reaction should have occurred because of the lack of a solvent effect on the self-sensitized photooxidation reaction rate at the early stage.

• Bulletin of the Korean Chemical Society
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• v.6 no.3
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• pp.124-127
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• 1985

The kinetic study on the bromine-exchange reaction of antimony tribromide with ${\alpha}$-phenylethyl bromide in nitrobenzene has been carried out, using Br-82 labelled antimony tribromide. The results show that the exchange reaction is first order with respect to ${\alpha}$-phenylethyl bromide, and either second or first order with respect to antimony tribromide depending on its concentration. It is also concluded that ${\alpha}$-phenylethyl bromide exchanges bromine atom with antimony tribromide much faster than other organic bromides previously examined. Reaction mechanisms for the exchange reaction are discussed.

• Bulletin of the Korean Chemical Society
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• v.3 no.4
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• pp.144-148
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• 1982

The kinetic study on the bromine-exchange reaction of antimony tribromide with t-butyl bromide in nitrobenzene or 1,2,4-trichlorobenzene has been carried out, using Br-82 labelled antimony tribromide. The results show that the exchange reaction is first order with respect to t-butyl bromide and 1.5th order with respect to antimony tribromide. It is assumed that the 1.5th order indicates the coexistance of first- and second-order kinetics. Reaction mechanisms for the exchange reaction are proposed.

• Bulletin of the Korean Chemical Society
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• v.21 no.12
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• pp.1213-1216
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• 2000

Localized structures with fronts connecting a Turing patterns and Hopf oscillations are found in discrete reaction-diffusion system. The Chorite-Iodide-Malonic Acid (CIMA) reaction model is used for a reaction scheme. Localized structures in discrete reaction-diffusion system have more diverse and interesting features than ones in continuous system. Various localized structures can be obtained when a single perturbation is applied with variation of coupling strength of two intermediates. Roles of perturbations are not so simple that perturbations are sources of both Turing patterns and Hopf oscillating domains, and spatial distribution of them is determined by strength of a perturbation applied initially.

• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.310-315
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• 1995

The heterobimetallic anion, (OC)5CrMn(CO)5-M+ (M+=Na+, PPN+), which has a donor-acceptor metal-metal bond1, was reacted with allyl bromide to yield BrCr(CO)5- and Mn(CO)5(CH2CHCH2). The reaction mechanism has been proposed in terms of the consecutive reaction pathway in which Cr(CO)5(THF) is an important intermediate leading to the corresponding product. Counterion effect on this reaction was also evaluated and the results were compared with those of the corresponding reaction of the mononuclear carbonyl anion, Mn(CO)5-.

• Korea-Australia Rheology Journal
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• v.17 no.4
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• pp.199-205
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• 2005

Carbon dioxide was absorbed into aqueous polyethylene oxide (PEO) solution containing AMP in a flat-stirred vessel to investigate the effect of non-Newtonian rheological behavior of PEO on the rate of chemical absorption of $CO_2$, where the reaction between $CO_2$ and AMP was assumed to be a first-order reaction with respect to the molar concentration of $CO_2$ and AMP respectively. The liquid-side mass transfer coefficient, which was obtained from the dimensionless empirical equation containing the properties of viscoelasticity of the non-Newtonian liquid, was used to estimate the enhancement factor due to chemical reaction. PEO with elastic property of non-Newtonian liquid made the rate of chemical absorption of $CO_2$ accelerate compared with Newtonian liquid based on the same viscosity of the solution.

• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.628-632
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• 2011

L-ribose has recently attracted interest as a starting material for antiviral drug. It could be obtained from L-arabinose by epimerization reaction. Epimerization reaction was carried out with molybdenium oxide or molybdic acid catalyst and methanol/water solution. Reaction temperature, methanol percentage, and catalyst kind were selected to find an optimum reaction condition. Ion exhange chromatography was used for separating epimerization reaction mixture, and then HPLC chromatogram of L-ribose fraction obtained to calculate the yield of the reaction. Shodex ion exchange HPLC column(Model SC1011) and Phenomenex Luna $NH_2$ HPLC column were compared to employ a convenient HPLC analysis. It was found that the usage of 20% methanol, $60^{\circ}C$, and 40 g/L molybdic acid gives the best reaction condition with a yield of 21%.

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.443-446
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• 2004

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3211-3212
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• 2011