• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.183-190
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• 1985

The elution behaviors of the rare earths was carried out in the iminodiacetic acid solution of various pH as eluent using ion exchange resin. The optimum eluent for the quantitative separation of $Eu^{3+},\;Pr^{3+},\;Ce^{3+}\;and\;La^{3+}$ were 0.0301M IMDA solution of pH 8.00 and 9.00 at 5cm column of the resin Dowex 50${\times}$8 (100-200 mesh). The elution order of the rare earth elements was in order of the atomic number of those elements. From the elution behavior of rare earth and u.v spectrum we found that the complexed rare earth species with IMDA changed according to pH of IMDA.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.434-443
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• 1987

The formation constants of the complexes between Ln-EDTA 1 : 1 complex and IMDA have been investigated by a potentiometric titration method at 20.0${\pm}$0.2 degree C and ${\mu}$ = 0.1 (KNO$_3$). Unusually large stability in Ln(EDTA) mixed ligand complexes was found. Trends in the formation constants vs. atomic number of the lanthanide metals were discussed on the basis of coordination number and ionic radius of the metals.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3254-3260
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• 2014

Intramolecular Diels-Alder (IMDA) reaction of vinylarenes bearing a Z-alkenyl tether, prepared from Morita-Baylis-Hillman (MBH) adducts, afforded arene-fused isoindoline derivatives in good yields. Vinylfurans, vinylthiophenes, and vinylnaphthalenes could be used successfully as dienes, while vinylbenzene failed under the same reaction conditions.

• Bulletin of the Korean Chemical Society
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• v.21 no.2
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• pp.159-160
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• 2000

• Archives of Pharmacal Research
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• v.17 no.2
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• pp.104-108
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• 1994

trans-Ethyl 1, 2, 3, 4a, 5, 6, 8a-cotahydro-2-benzyl-4-hydroxy-6-methyl-5-isoquinoline-carboxylate was prepared by intramolecular Diels-Alder reaction as a precusor of newly designed aza-analogue of mevinolin.

• Journal of the Korean Chemical Society
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• v.41 no.11
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• pp.612-638
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• 1997

The methods of separation and recovery of rare earth elements in monazite sand have been studied by the ion exchange chromatography. Both of cation and anion exchange resin were used as ion exchange resins and the solutions of EDTA, DTPA, IMDA and Ln-EDTA were used as eluents. The H+, Zn2+, Fe3+, Al3+, Cu2+, and NH4+ forms of cation exchange resin were used as retaining ions. Ln-EDTA solution was loaded on the EDTA form of anion exchange resin and separated. The Ln-EDTA solution was also used as an eluent for a selective separation of one element from the rare earth mixture solution. The size effects of resin column, the elution mechanism for the various elution types and the separation of a large amount of rare earths were studied.