• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.428-429
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• 2005

Novel fluoroionophore of dibenzothiazolyl-dibenzo-crown ethers were synthesized from diformal-dibenzo 18-crown-6 (24-crown-8) with 2-aminothiophenol, and they were characterizated by $^1H$-NMR, $^{13}C$-NMR, IR spectrum, Mass spectrum, elemental analyses, respectively. The fluorescent properties of the newly synthesized crown ether were examined with $Li^+$, $Na^+$, $K^+$, $Rb^+$, $Cs^+$, $NH_4^+$ and $CF_3COOH$, respectively. With protonation using $CF_3COOH$, the absorption bands of the new crown ethers are further blue shifted, the maximum emission wavelengths further red shifted.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.61-62
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• 1993

고분자 분리막의 투과성과 선택성을 향상시키기 위하여 IPN막, 고분자/액정 복합막을 다양한 기능을 가진 재료가 개발되고 있다. 본 연구에서는 알칼리메탈이온을 분리하기 위하여 고분자 지지체에 운반체로써 crown ether(macro-cyclic polyether)류를 분산시킨 고분자/운반체 복합박막을 제조하였다. 고분자/운반체 복합박막은 고분자와 운반체의 혼합용액을 수면에 전개시켜 제조하였다. 고분자는 PVC(M.W 60000, Aldrich), PS(M.W 280000, Aldrich)와 CA(M.W 30000, Sigma)를 사용하였고, 운반체로는 crown ether 중 $K^+$이온과 선택성을 가지는 18-Crown-6(Sigma)를 사용, 고분자와 18-Crown-6의 증량분을 달리하는 혼합용액을 제조하였다. 이때 용매는 Tetrahydrofuran를 사용하였다. 수면에 생성된 박막을 다공성 지지막에 적층시킨 후 감압 건조시켜 복합막을 제조하였다. 고분자와 운반체가 혼합되어 있는 용액의 점도와 표면장력을 각각 fluid spectrometer와 tensionmeter를 사용, 용액이 수면위에서 완전한 막을 형성하면서 분산될 수 있는지 조사하였으며, 고분자 지지체에 분산 고정된 운반체의 분산형태와 표면농도를 조사하기 위하여 ESCA를 이용하였다.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1553-1556
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• 2006

A diazatetrathia crown ether derivative that has two appended nitrobenzoxadiazolyl moieties showed selective OFF-ON type fluoroionophoric signaling properties toward Hg2+ ions over other transition metal ions. The compound also exhibited a pronounced chromogenic behavior toward Hg2+ ions by changing the solution color from light orange to yellow, which can easily be detected with naked-eye. The detection limit for the analysis of Hg2+ ions in 90% aqueous acetonitrile was found to be 4.8??10-6 M, which suggests that the compound may be used as a chemosensor for analyzing sub-millimolar Hg2+ ions in aqueous environments.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.567-570
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• 2008

A new pyrene appended diaza-18-crown-6 ether derivative 1 has been prepared and its fluoroionophoric properties toward transition metal ions were investigated. Compound 1 exhibited a high Hg2+-selectivity over other transition metal ions as well as alkali and alkaline earth metal ions in aqueous acetonitrile solution. The ratiometric analysis of the monomer and excimer emissions of pyrene successfully signals the presence of Hg2+ ions. The detection limit for Hg2+ ions was found to be 3.1 ´ 10-6 M in 50% aqueous acetonitrile solution at pH 8.1. Competition experiments also suggest that the compound could be utilized as a selective and sensitive fluorescent chemosensor for the analysis of micromolar Hg2+ ions in physiological and environmental samples.

• Bulletin of the Korean Chemical Society
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• v.25 no.3
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• pp.361-364
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• 2004

The potentiometric response of electrode no. 4 based on 1,3-bisbridged cofacial-calix[6]crown-5-ether (IV) gave a sub-Nernstian (45.0 mV/decade) response and the best detection limit (-log $a_{ep}$ = 4.73) towards epinephrine. The responses are decreasing in the order of epinephrine > $K^+$, dopamine > $NH_4^+$ > norepinephrine > $Na^+$. It is remarkable that the proposed electrode shows the reasonable selectivity to epinephrine against other catecholamine neurotransmitters (dopamine and norepinephrine) as well as alkali metal ions.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1737-1740
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• 2006

The optimized structures and complexation energies of bis(18-crown-6-ether) analogue (2) of Trgers base (1) with a series of primary alkylbisammonium ions have been calculated by DFT B3LYP/6-31G(d,p) method. The calculated complexation efficiency (-142.84 kcal/mol) of 2 for butane-1,4-diylbisammonium guest is better than twice of the value (-61.40 kcal/mol) for butylammonium ion. The multiple hydrogen-bond abilities for the complexes are described as the function of the length of the alkyl substituents of the bisammonium guests with normal-alkyl chain [$-(CH_2)_{n-}$, n = 4-8]. The longer bisammonium guest shows the stronger hydrogen-bonding characterizations (the distance and the quasi-linear angle of the N-H…O) to the host 2 than the shorter bisammonium ions. These calculated results agree with the experimental data of the complexation of 2 with bisammonium salts ([$NH_3(CH_2)_nNH_3$] $Cl_2$).

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1641-1644
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• 2004

Several [2]- and [3]rotaxanes bearing some functional groups on their wheel components and spacers with different lengths between two ammonium centers on their dumbbell components were prepared in good yields from dibenzo-24-crown-8-ether derivatives and dumbbell-shaped bis(sec-ammonium salt)s having a centrally located disulfide linkage, by utilizing the reversible thiol-disulfide interchange reaction. The shuttling behaviors of the [2]rotaxanes were investigated by $^1H$ NMR by use of the spin polarization transfer-selective inversion recovery technique. It was found that the change in spacer length in the axle resulted in a drastic change in shuttling rate of the [2]rotaxanes, although the introduction of the functional groups to the wheels did not affect the shuttling behavior at all.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.155-158
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• 2003

New porphyrin square (1) was prepared by reaction of porphyrin containing pyridine and Re$(CO)_5Cl$ in THF/toluene solvent. 2-(Methylene15-crown-5)-nicotinoly ester(2) was synthesized by reaction of 2-(Hydroxymethyl-15-crown-5 and nicotinoly chloride in $CH_2Cl_2$. In fluorescence quenching studies luminescence was quenched by addition of the guest(2) into host(l). In the host-guest system we could obtain binding constant (K= $1.13{\times}10^{7}M^{-1}$) at decreasing concentration of (2). But the luminescence was dramatically increased after $Na^{+}$ was added into the host-guest system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.08a
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• pp.133-136
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• 2003

New porphyrin square (1) was prepared by reaction of porphyrin containing pyridine and $Re(CO)_5Cl$ in THF/toluene solvent. 2-(Methylenel5-crown-5)-nicotinoly ester(2) was synthesized by reaction of 2-(Hydroxymethyl-15-crown-5 and nicotinoly chloride in $CH_2Cl_2$. In fluorescence quenching studies luminescence was quenched by addition of the guest(2) into host(l). In the host-guest system we could obtain binding constant (K=$1.13{\times}10^7M^{-1}$) at decreasing concentration of (2). But the luminescence was dramatically increased after $Na^+$ was added into the host-guest system.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.61-67
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• 1995

PVC membrane electrodes based on the lipophilic neutral carrier, dibenzo-18-crown-6, cyclic oligomers of teit-butylphenol-formaidehyde condensates, calix[4]arenes as the active sensors for verapamil have been prepared and tested in a variety of plasticizers. At pH 5.0, the electrode exhibits a Nernstian response in the range of 10$^{-2}$~5$\times$10$^{-5}$ M verapamil with a slope of 49.1$\pm$0.5mV per concentration decade. The electrode constructed in this work can be used continuously for at least 1 month before any damage to the membrane occurs. And the analyses of the local anesthetic amine, which are good to select a specific compound in a mixed solution, were also accomplished by using of another neutral carrier, a DB18C6, for comparing with calix[4]arene.