• Bulletin of the Korean Chemical Society
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• 제28권4호
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• pp.538-542
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• 2007

Polymeric electrodes for lead ion based on N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine as an ion carrier were prepared. The membrane electrode (m-3) containing o-NPOE as a plasticizer and 50 mol% additive of ionophore gives an excellent Nernstian response (29.59 mV/decade) and the limit of detection of ?log a (M) = 5.74 to Pb2+ in Pb(NO3)2 solution at room temperature. The prepared electrode provided good sensitivity and outstanding selectivity and response for Pb2+ over a wide variety of other metal ions in pH 7.0 buffer solutions. The good sensitivity and selectivity towards lead ion are attributed to the strong complexation of lead ion to N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine which has geometrically the proper cavity to coordinate to the ligand.

• 멤브레인
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• 제25권3호
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• pp.231-238
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• 2015

본 연구에서는 부분지환족 dianhydride인 5-(2,5-dioxotetrahydrofuryl)-3-methyl-cyclohexene-1,2-dicarboxylic anhydride (DOCDA)와 다섯가지 diamine (2,5-dimethyl-1,4-phenylene diamine (2M), 2,4,6-trimethyl-1,3-phenylene diamine (3M), 1,5-naphthalene diamine (NDA), 4,4-diaminodiphenyl methane (MDA), 4,4'-diaminodiphenyl ether (ODA))을 two-step 이미드화를 통해 공중합하였다. 합성된 폴리이미드 공중합체를 FT-IR, 고유점도, DSC, TGA 그리고 용해도 측정을 통해 구조분석 및 물성을 확인하였다. 또한 6FDA를 dianhydride로 한 공중합체를 같은 방법으로 합성하여 함께 비교하였다. 그 결과, 모든 공중합체는 0.32~0.58의 고유점도를 가졌으며, DOCDA계 공중합체는 6FDA를 포함한 공중합체보다 약간 낮은 값을 보이나 약 $400^{\circ}C$까지 견딜 수 있는 열적 안정성과 여러 가지 용매에 대한 우수한 용해성을 나타내었다. 또한 얻어진 폴리이미드를 이용해 평막을 제조하여 $CO_2$ 및 $CH_4$에 대한 기체투과도를 평가하였고 공중합체는 구조변화에 따른 투과-선택도의 상충관계를 보여주었다.

• Bulletin of the Korean Chemical Society
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• 제25권9호
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• pp.1336-1340
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• 2004

The same kind of chiral stationary phase with a commercialized chiral column was used to make preparative chiral columns and was applied to resolve racemic N-acetyl-1-naphthylethylamide (3) by preparative liquid chromatography. An improved chromatographic condition to resolve racemic 3 on the CSP was examined by changing flow rate and kind of the mobile phase and the sample injection volume. The optimized separation conditions were applied to resolve racemic 1,1'-Binaphthyl-2,2'-diamine(4).

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1593-1596
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• 2006

The polymeric membrane electrodes based on N,N'-bis-pyridin-2-ylmethylene-naphthalene-1,8-diamine as an ion carrier were prepared and tested for the copper-ion selective electrode. The membrane has a linear dynamic range between $10^{-6}$ and $10^{-2}$ M with a Nernstian slope of 29.6 mV per decade, and its detection limit was $10^{-5.62}$M. The potentiometric response is independent of the pH range of 3-5. The proposed electrode showed good selectivity and response for $Cu^{2+}$ over a wide variety of other metal ions in pH 4.0 buffer solutions.

• 공업화학
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• 제4권4호
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• pp.814-822
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• 1993

용해성과 접착력을 향상하기 위하여 우레탄 그룹을 함유하는 디아민-퀴논 중합체를 합성하고 특성분석을 행하였다. 디이소시아네이트와 저분자량의 디올을 반응시켜 NCO말단 프리폴리머를 합성한 다음 NCO그룹을 아민으로 변화시켜 우레탄기를 함유하는 디아민을 제조하였다. 이때 NCO/OH몰 비율을 1.2에서 2.1까지 변화시켜 디아민 분자량을 변화시켰다. 이러한 디아민기를 함유하는 프리폴리머를 p-벤조퀴논과 반응시켜 디아민-벤조퀴논 중합체를 제조하였다. 중합체의 분석에는 분광분석기와 크로마토그래피를 이용하여 분자구조 분석과 분자량을 측정하였으며, 용해도와 열적 거동도 측정 검토하였다.

• 한국산업융합학회 논문집
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• 제3권1호
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• pp.77-82
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• 2000

The stereoselective ligand exchange reaction of trans-$[Co(SS-epm)Cl_2]^+$ and racemic propane-1,2-diamine (rac-pn) produces the complex that is identified as $[CO(N)_6]^{3+}$ type of $[Co(SS-epm)(pn)]^{3+}$ by absorption spectrum. It is conceivable that the reaction mechanism involves substitution and isomerization. The calculated and experimentally determined ratios of the complexed enantiomeric substrates at equilibrium were as follows: $[Co(SS-epm)(pn)]^{3+}$,calcd 32 % / 68 %, exptl 19 % / 81 % R-pn / S-pn. It has been shown that the employment of molecular mechanics calculations as a predictive tool may lead to the design of chiral complexes that may be applied to the separation of racemic mixtures of simple bidentate ligands.

• 약학회지
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• 제35권3호
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• pp.190-196
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• 1991

N-monoalkyiations of ditertiary diamines succeed best in nitromethane or ethanol at low temperature, unsymmetrical piperazine and piperidine compounds react selectively under these condition at the sterically less hindered nitrogen atom.

• 대한화학회지
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• 제13권4호
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• pp.309-312
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• 1969

A series of metal ion-2, 5-diamine 1, 4-dihydroxybenzene polymers containing copper(II), nickel(II) or cobalt (II) have been prepared. The structure was postulated on the basis of elementary analysis of polymers. It was found that copper polymer is most likely the coordination polymers by X-ray powder pattern studies. The thermal stability of the polymers was also studied by a simple method, utilizing a thermogravimetric balance. The order of thermal stabilities is Cu(II) > Ni(II) > Co(II). The polymers start to decompose at a relatively low temperature.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2960-2964
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• 2011

The efficient asymmetric hydrosilylation of imines in the presence of polymethylhydrosiloxane has been investigated by screening chiral diamine-zinc complexes. A series of chiral diamine ligands were prepared from optically pure 1,2-diphenyl-1,2-ethanediamine and screened for effectiveness. N-Benzylic substituents were required for high enantioselectivity; ligands with bulky groups or extra coordinating groups such as OH and S lowered the catalytic activity. The level of asymmetric induction was usually in >90% ee range for aromatic imine substrates. A linear correlation between the ee of the ligand and that of the product was observed, indicating the presence of a 1:1 ratio of ligand to metal coordination in the active catalytic complex.

• Bulletin of the Korean Chemical Society
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• 제8권6호
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• pp.441-444
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• 1987

The circular dichroism(CD) spectra of the optically active [$Co(acac)_2(diamine)]^+$ complexes were measured in the several protic and aprotic solvents, where acac = acetylacetonate anion and diamine = ethylenediamine and trimethylenediamine. The degree of the CD variation in protic solvents was enhanced as the dielectric constant decreases except n-butanol and benzylalcohol. And the degree of the CD variation in aprotic solvents was roughly increased as both dipole moment and dielectric constant decrease except aromatic solvents and the solvents having no dipole moment. It was deduced that the CD variations of the complexes have been due to the conformational change of acetylacetonate ligands coordinated to Co(III) ion.