• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.287-292
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• 1992

The rate constants of the nucleophilic addition reaction of amines (piperidine and diethylamine) to phenylvinylketone in various solvents have been determined by UV spectrophotometry at $25^{\circ}C$. On the basis of the high sensitivity of the rate to the polarity of the medium, it may be concluded that the reaction intermediate has zwitterionic character. The effect of the solvents on the rate of the bimolecular nucleophilic addition reaction is described well by the Kirkwood equation: The transition state of the reaction has a cyclic structure formed through an intramolecular hydrogen bond. The addition reaction of primary and secondary amines to phenylvinylketone in all solvents take place considerably faster than that of tertiary amine and this results also can be explained by the intermediate products in the reaction have a cyclic structure formed through an intramolecular hydrogen bond for the primary and secondary amines but not for the tertiary amine.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.105-107
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• 1998

• Resources Recycling
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• v.26 no.2
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• pp.3-10
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• 2017

Rare earth elements with high purity are demanded for the manufacture of advanced materials. Light rare earth elements are contained in domestic monazite and Ni-MH batteries. In this paper, solvent extraction to separate the light rare earth elements from hydrochloric acid leaching solutions of these resources was discussed. A mixture of cationic and tertiary amine shows synergistic effect on the extraction of LREEs and the extent of pH decrease during extraction is reduced. The effect of solution pH on the extraction and synergism was reviewed. Acquisition of the operation data with mixer-settler on the separation of LREEs by this mixture is necessary to develop a process.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.11
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• pp.607-612
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• 2017

The effect of carbonic anhydrase on $CO_2$ absorption rates and the heat of reaction were evaluated in various amine solutions for post combustion $CO_2$ capture process. The $CO_2$ absorption rate was analyzed in 30 wt% MEA, AMP, DMEA, MDEA aqueous solutions with and without carbonic anhydrase (250 mg/L) from bovine erythrocyte. $CO_2$ absorption rates were increased in all solutions with carbonic anhydrase. The effect of carbonic anhydrase on absorption rates was more in tertiary amine (DMEA and MDEA) solutions than in primary amine (MEA) and hindered amine (AMP) solutions. The heat of reaction of MEA, DMEA, MDEA aqueous solutions with and without carbonic anhydrase were measured using reaction calorimeter. Carbonic anhydrase decreased the heat of absorption in all solutions. The results suggested that tertiary amines that have the excellent desorption ability were suitable for applying carbonic anhydrase to the post combustion $CO_2$ capture process and the effect of carbonic anhydrase was best in MDEA solution.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.743-748
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• 1994

Photochemical reactions of saccharin with tertiary amines were explored. Saccharin was found to undergo an acid-base reaction with N-trimethylsilylmethyl-N,N-diethyl amine to form N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin salt which is in equilibrium with free saccharin and N-trimethylsilylmethyl-N,N-diethyl amine insolution. Photoreaction of N-trimethylsilylmethyl-N,N-diethyl ammonium saccharin in $CH_3OH\;or\;CH_3CN$ results in the generation of desilylmethylated product, N,N-diethyl ammonium saccharin mainly along with benzamide. Photoreaction of N-methylsaccharin with N-trimethylsilylmethyl-N,N-diethyl amine in $CH_3OH$ leads to the production of o-(N-methylcarbamoyl)-N-ethylbenzenesulfonamid e as the major product along with N-methylbenzamide as the minor product. On the other hand, photoreaction of N,N,N-triethyl ammonium saccharin, generated from saccharin and triethylamine, produces N-methylbenzamide as the exclusive product. These photoreactions are quenched by oxygen indicating that triplets of saccharin and N-methylsaccharin are the reactive excited states. Based on the consideration of the redox potentials of saccharin and N-trimethylsilylmethyl-N,N-diethyl amine, and the nature of photoproducts, pathways involving initial triplet state single electron transfer are proposed for photoreactions of the saccharins with the ${\alpha}$-silylamine.

• Journal of the Korean Chemical Society
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• v.6 no.2
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• pp.148-154
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• 1962

The reactions between organic halides$(CCl_4,\;C_6H_5Br,\;C_6H_5Cl,\;C_6H_5I)$ and amines $(C_6H_5NH_2,\;R_2NH,\;R_3N,\;(CH_2)_5NH,\;pyridine)$ were studied under mixed u.v. irradiation. The modes of reactions were examined by means of gas chromatography and product-reactant ratio determination. The reaction of $CCl_4$ with amines give chloroform and hexachloroethanes, and the reaction of aromatic halides with amines gave biphenyl and benzene. In each series of reaction there obtained mainly corresponding amine hydrohalides, but no amination products. The reactivity was in the order of the basicity of amines and of the reactivity of organic hahides, except in the case of cyclic tertiary amine. The result was interpreted as a non-chain photodecomposition process. A competitive proton abstraction reaction path via the formation of a change transfer complex was proposed as the reaction mechanism.

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.406-409
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• 1997

The various cobalt(Ⅱ) complexes were synthesized and characterized using tris-(2-benzimidazolylmethyl)amine (ntb) as a ligand where the ntb plays as a tripodal tetradentate ligand to form complexes with a trigonal pyramidal geometry. The complexes have 5 and 6 coordinate cobalt(Ⅱ) ions depending on the additional ligand used. In each complex the additional ligand, chloride anion, or acetate anion occupies the "open" site trans to the apical tertiary nitrogen atom of ntb ligand. Complex 1, [Co(Ⅱ)(ntb)Cl]Cl has a trigonal bipyramidal geometry. This geometry was easily constructed using ntb as a tetradentate ligand and chloride as a monodentate ligand. The complex is isostructural to the corresponding manganese(Ⅱ) complex. Crystal data are as follows: [Co(Ⅱ)(ntb)Cl]Cl·MeOH, 1. triclinic space group P1; a=13.524(2) Å, b=14.037(2) Å, c=17.275(1) Å; α=78.798(9), β=84.159(8)°, γ=65.504(9)°; V=2929.6(6) Å3; Z=4; R1=0.0715, wR2=0.1461 for reflections of I > 2σ(I). Six coordinate complex 2 [Co(ntb)(OAc)](OAc) was synthesized using ntb as a tetradentate ligand and acetate as a bidentate chelating ligand.

• Korean Journal of Pharmacognosy
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• v.1 no.3
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• pp.93-99
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• 1970

There have been reported by several workers for the isolation and determination of the amine derivatives as Metbylephedrine Hydrochloride and Ephedrine Hydrochloride adopting neutralization method, steam distillation method, non-aqous titration method, ion-exchange resin method, titration method after acetylation, colorimetric method, gravimetric method, iodine titration method and gas chromatography. Those methods mentioned in above, can be practically applied for the sample which is not mixed one mith the other amine compounds. Presently, it has not shown on the isolative determination of the mixed sample of amine derivatives. In this paper, it is discussed on the isolative determination of Methylephedrine Hydrochloride as the tertiary amine compound and Ephedrine Hydrochloride as the secondary amine compound. According to the results of the experiment, it could be summarized as follows: 1. There is no time-variation on the color reaction of Methylephedrine Hydrochloride and Ephedrine Hydrochloride with the color reagent, bromcresolgreen. And Methylephedrine Hydrochloride and Ephedrine Hydrochloride, respectively, can be determined spectrophotometrically by means oft his color reaction. 2. For the isolation of Methylephedrine Hydrochloride and Ephedrine Hydrochloride from the mixed sample, Methylephedrine Hydrochloride can be eluted by chloroform, while Ephedrine Hydrochloride by the mixed solvent of chloroform and ethylalcohol (2:1), from the celite column adsorbed at pH6.4 followed by extraction with ether undersodium hydroxide alkali re action. 3. When the sample is mixed with quinine hydrochloride, dihydrocodeine bitartate, and noscapine, these mixed compounds can be eliminated by means of stram distillation. 4. When the sample is mixed with chlorpheniramine maleate, dextromethorphan hydrobromide and diphenhydramine hydrochloride, the mixed compounds can be eliminated by means of steam distillation and celite adsorption column chromatography, In conclusion, the isolative determination method for Methylephedrine Hydrochloride and Ephedrine Hydrochloride studied in this paper, indicates with the excellent reproducibility and accuracy.

• Journal of Hydrogen and New Energy
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• v.28 no.5
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• pp.561-569
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• 2017

In this study, a synthetic amine made using the ethylene oxide-ammonia reaction was used as an absorbent to remove carbon dioxide. Existing absorbents were used in a mix in order to improve performance; however, because the ethylene oxide-ammonia reaction generates primary, secondary, and tertiary amines simultaneously, it has the merit that separate mixing of the absorbents was not needed. The performance of carbon dioxide absorption with the synthetic amine was compared to that of MEA. As a result of an experiment, it was determined that the $CO_2$ loading was 1.15 times better than that of MEA (a commonly used amine), while the cyclic capacity was 2.28 times higher. Because the heat of reaction was 1.10 times lower than for MEA, the synthetic amine showed superior performance in terms of absorption and regeneration.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.121-126
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• 1994

To elucidate the effect on the reactive extraction of acetic acid, various carriers and modifiers were investigated. Carriers used were secondary and tertiary amines and solvation extractant. Diluent was n-butylacetate. Modifiers were 4-nonylphenol, TBP(Tti-n-butyl phospate) and isodecanol. Besides the effect of temperature and pH in aqueous phase were studied. The mixture of 50% tri-n-octyl/n-decylamine tertiary amine, gave higher degree of extraction and selectivity than other extractants in the extraction of acetic acid. It was found that 4-nonylphenol as modifier fairly good. The degree of extraction was higher with decreasing the pH in aquous phase and the temperature of extraction system.