• 대한화학회지
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• 제37권8호
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• pp.773-778
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• 1993

Tl$^+$이온 센서로서 크라운 에테르 B15C5와 DB18C6를 중성운반체로 한 PVC 액체막 이온 선택성 전극을 제작하였다. 막용매로는 DOA, NPPE 및 NPOE를 사용하였으며 친유성 염, KTClPB의 농도를 변화시킨 여러가지 조성의 막을 시험하였다. B15C5와 DB18C6 막 전극의 감응전위는 농도범위, 10$^{-1}$∼10$^{-5}$M에서 직선으로 나타났으며 최대 기울기는 전극에 따라서 40∼55 mV/decade였다. 선택계수는 분리용액법으로 결정하였으며 알카리금속 이온, 알칼리토금속 이온 및 일부 전이금속 이온에 대하여 좋은 선택성을 나타냈다. 제작된 액체막 전극은 Ph > 3 에서 안정한 감응전위를 보였다.

• KSBB Journal
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• 제27권4호
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• pp.199-206
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• 2012

Chiral crown ethers are synthetic macrocyclic polyethers that bind protonated chiral primary amines with high selectivity and affinity. They have been widely used to separate or distinguish the enantiomers of chiral compounds containing a primary amino moiety by high-performance liquid chromatography, capillary electrophoresis, and NMR spectroscopy. In this paper, two important chiral crown ethers including chiral binaphthyl unit and (18-crown-6)-2,3,11,12-tetracarboxylic acid as chiral selectors are focused. And several chiral resolution techniques and their applications in chirotechnology using these chiral crown ethers with related chiral recognition mechanism studies are reviewed. Especially, it was shown that the commercially available HPLC columns based on (18-crown-6)-2,3,11,12-tetracarboxylic acid have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• KSBB Journal
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• 제27권4호
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• pp.232-236
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• 2012

Comparative liquid chromatographic enantiomer separation of ${\alpha}$-amino acids, their esters and primary amino compounds was performed using two chiral stationary phases (CSPs) prepared by covalently bonding (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) of the same chiral selector. In general, the separation factors and resolution factors for these analytes on CSP 1 were greater than on CSP 2, while these capacity factors on CSP 2 were quite greater than on CSP 1. Except for leucine methyl ester and phenylalanine methyl ester, the elution orders of all analytes including ${\alpha}$-amino ${\alpha}$-alkyl acids and phenylglycine alkyl esters on CSP 1 are identical to those on CSP 2. This study showed that different connecting structures for these two CSPs might influence their ability to resolve the analytes depending on their structures related to the chiral recognition mechanism.

• 한국산업융합학회 논문집
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• 제6권1호
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• pp.73-80
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• 2003

We report herein synthetic results obtained six new types of bis-benzocrown ethers containing imine group. Bis crown ethers1~3 are aminobenzo-15-crown-5-ether linked with terephthalaldehyde, isophthalaldehyde, phthaldehyde respectively by imine reaction. Bis crown ethers1~3 are different distances in each crown ether rings. Bis crown ether 4 has large cavity in crown ethers. Functionalized crown ether 5 is synthesized amonobenzo-15-crown-5-ether and terephthaladehyde same ratio at one to one. Bis crown ether 6 has photosensitive linkage between crown ethers. Bis crown ether 7 is prepared by amonobenzo-15-crown-5-ether and triethyl ortho formate. 4'-Nitrobenzo-crown ethers and 3',4'-dinitrobenzo-crown ethers were prepared by nitration of benzo crown ethers, obtained from the reaction of catechol and oligoethylene glycol ditosylate. Crown ethers containing aldehyde group were synthesized from the reaction of 3,4-dihydroxybenzaldehyde and corresponding ditosylate respectively. The synthesized crown ethers were characterized respectively by IR, NMR, GC-Mass.

• 한국응용과학기술학회지
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• 제22권1호
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• pp.50-55
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• 2005

A comparison of alkali metal cation and alkaline earth cation solvent extraction was made for three additional monoionizable crown ethers and one diionizable crown ether. sym-(n-Octyldibenzo)-16-crown-5-oxyacetic acid $\underline{1}$ exhibited high efficiency and selecvity in solvent extraction of alkali metal cations with respect to that observed with alkaline earth cations. Sizes of $Na^+$ and $Ca^{2+}$ appropriately match with the cavity size of monoethyl sym-bis[4(5)-tert-butylbenzo]-16-crown-5-oxymethylphosphonic acid $\underline{3}$. As the result, $Na^+$ and $Ca^{2+}$ are the best extracted. sym-(n-Octyldibenzo)-16-crown-5-oxymethyldiphosphonic acid $\underline{4}$was found to be somewhat selective for $Na^+$ over $Li^+$ and other alkaline earth metal cations. In the complexation of alklaine earth cations by crown ether diphosphonic acid $\underline{4}$, $Ca^{2+}$ and $Sr^{2+}$ are the appropriate sizes, but lager $Ba^{2+}$ may be due to favorable formation of a sandwich type complex between the crown ether cavity and the dianion of the deprotonated crown ether phoaphonic acid moiety.

• 한국산업융합학회 논문집
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• 제6권2호
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• pp.109-113
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• 2003

We report herein synthetic results obtained new types of crown ethers containing coumarin group. Crown ethers containing coumarin group 1~3 are hydroxymethyl-15-crown-5-ether linked with 4-hydroxy coumarin-4-acetic acid by esterification reaction. Crown ethers containing coumarin group 1~3 have different cavity in each crown ether rings. The 12-crown-4 ether with coumarin 1 has the smallest cavity size. The 15-crown-5 ether with coumarine 2 has the medium cavity size. The 18-crown-6 ether with coumarin 3 has the largest cavity size. Therefore each crown ether with coumarin group will recognize different ionic radius meta. Because of different hole size in crown ethers, these crown ethers seem to be had different selectivity in luminescent sensors. The crown ethers with coumarine 1~3 synthesized hydroxymethyl-15-crown-5-ether and 4-hydroxy coumarin-4-acetic acid same ratio at one to one. The synthesized crown ethers were characterized respectively by IR, NMR. GC-Mass.

• 대한화학회지
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• 제40권2호
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• pp.117-121
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• 1996

Crown 고리 근방에 질소, 황원자 를 포함하는 새로운2종의 crown ether를 합성하였다. 4'-Benzothiazolylbenzo-12-crown-4 (1) 4'-Benzothiazolylbenzo-15-crown-5 (2)는 각각 4'-formylbenzo-12-crown-4 (3)및4'-formylbenzo-15-crown-5 (4)와 2-aminothiophenol과의 반응에 의해 합성하였다. (3)과(4)는 3, 4-dihydroxybenzaidehyde와 tri-및 tetraethyleneglycolditosylate와의 반응에 의해 합성하였다. Triethyleneglycolditosylate와 tetraethyleneglycol ditosylate는 NaOH 존재하에서 triethyleneglycol, tetraethyyleneglyco.과 p-toluenesulfonyl chloride의 반응에 의해 합성하였다.

• 대한화학회지
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• 제36권5호
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• pp.669-673
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• 1992

알칼리금속이온(Li^+, Na^+, K^+, Rb^+, and Cs^+)과 아미드기를 포함하는 피리디노아자 크라운 화합물인 DBPDA와 PDA의 착물형성에 대한 안정도상수, K를 전기 전도도법을 이용하여 여러 온도에서 측정하였다. 각 온도에서 K값은 DBPDA의 경우 Cs^+ > K^+ > Rb^+ > Li^+ > Na^+의 순서였으며, PDA의 경우는 Cs^+ > K^+ > Rb^+ > Li^+ > Na^+이었다. 또한 DBPDA가 PDA보다 이들 알칼리 금속 이온에서 더 큰 K값을 보여주었다. 넓은 의미를 갖는 "Hole-Size-Selectivity" 원리에 이들 착물은 적용되지 않는 것으로 나타났다. 온도 변화에 따른 K값으로부터 {\delta}H와 T{\delta}S를 각각 구했으며, 이들 반응들은 엔탈피 기여에 따르는 착물형성반응으로 나타났다. 그러나 PDA의 경우 부분적인 엔트로피 항의 증가도 착물의 형성에 기여함을 알았다.

• 대한화학회지
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• 제37권5호
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• pp.491-495
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• 1993

고분자물질로 지지된 아자크라운 에테르(polymer supported azacrown ether:DBPDA ion exchanger)를 합성하고, 이 이온교환체와 Li, Na, 그리고 K의 피크레이트염과의 이온결합등에 대하여 알아보았다. 그리고, DBPDA 이온교환체와 알칼리 피크린산염의 에테르형 용매내에서 알칼리 금속이온들의 결합상수(binding constant:Kb)를 분광광도법을 통하여 구하였다. 그 결과, 결합상수의 크기는 Li < Na < K 순으로 증가하였으며, 리간드와 1:1 착물을 형성한다는 것을 알 수 있었다. 또한 이들의 Kb값들은 용매 및 온도 등과 같은 것들에 의하여 변화하였으며, 그 값들은 $2{\times}10^3{\sim}4{\times}10^4M^{-1}$ 범위내에 있었다. 한편 이들 착물형성 과정에서의 엔탈피 및 엔트로피 변화, ${\Delta}$H 및 ${\Delta}$S는 10~40$^{\circ}C$ 온도 범위내에서 van't Hoff plot으로부터 구했으며, 이들의 값들은 각각, -2.71∼-3.79 kcal/mol과 -16.52∼-20.57 eu 범위내에 있었다.

• 대한화학회지
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• 제37권9호
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• pp.781-786
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• 1993

$Mg^{2+}$ 존재하에서 비이온성 계면활성제 $nonylphenol-(ethylene oxide)_n$[NP-nEO; n = 12, 40, 100]와 요오드간의 상호작용을 UV-visible spectrophotometer를 이용하여 수용액 중에서 조사하였다. CMC (Critical micelle concentration)는 $Mg^{2+}$ 농도 증가에 따라 감소하였으며, 그 감소폭은 EO(ethylene oxide) 수에 크게 의존하였다. CMC 이상에서 $Mg^{2+}$ 첨가에 따른 상호작용 피크와 강도는 증가하다가 감소하는 변곡점을 보였다. 상호작용 피크의 강도 증가는 $Mg^{2+}$ 존재하에서 미셀구조가 더욱 조밀해진데 따른 요오드와의 전자주게-받게 겹침증가로 볼 수 있다. 이러한 현상들은 비이온성 계면활성제 미셀표면에 노출된 EO 사슬이 유사크라운에테르 구조를 형성하여 $Mg^{2+}$ 의 착물을 형성할 수 있는 가능성을 보여준다.