• 한국환경과학회지
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• 제15권8호
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• pp.799-809
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• 2006

Hydrobromic acid salts of new N, N, O tridentate ligands containing phenol, 2-[(2-Methylamino- ethyl- amino)-methyl]-phenol(H-MMP. 2HBr), 5-Bromo-2-[(2-Methylamino-ethylamino)-methyl]-phenol (Br- MMP. 2HBr), 5-Chloro-2-[(2-Methylamino-ethylamino)-methyl]-phenol(Cl-MMP. 2HBr), 5-Methyl-2-[(2-Methylamino-ethylamino)-methyl]-phenol(Me-MMP. 2HBr), 5-Methoxy-2-I(2-Methylamino-ethylamino)- methyl]-phenol(MeO- MMP. 2HBr) and. 1-[(2-Methylamino-ethylamino)- methyl]-naphthalen-2-ol(Nap- MMP. 2HBr) were synthesized. The synthesized ligands were confirmed by C. H. N. atomic analysis, UV-visible and IR spectroscopies, $^1$H NMR, $^{13}$C NMR and mass analysis. The potentiometry study revealed that the proton dissociation constants(logK$_n^H$) of the synthesized ligands and stability constants (logK$_{ML}$, logK$_{LM2}$) of transition metal complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II) ions occurred in three steps and the order of the calculated overall proton dissociation constants(log$\beta_p$) and stability constants (logK$_{ML}$) of ligands was Br-MMP. 2HBr < Cl-MMP 2HBr < H-MMP. 2HBr < Nap-MMP. 2HBr < Me-MMP. 2HBr < MeO-MMP. 2HBr. The order showed a similar trend to that of Hammett substituent constants($\delta_p$). The synthesized ligands usually form 2:1(ML$_2$) complexes with transition metal ions. The order of the stability constants of each transition metal ions was Co(II) < Ni(II) < Cu(II) ;> Zn(II) ;> Cd(II) ;> Pb(II).

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.51-56
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• 2005

A PVC membrane electrode for lead ion based on 1-phenyl-2-(2-quinolyl)-1,2-dioxo-2-(4-bromo) phenylhydrazone (PQDBP) as ionophore was demonstrated. The optimum composition of the membrane was 30 wt% poly(vinyl chloride), 60 wt% dibutyl phthalate as a plasticizer, 4 wt% ionophore and 6 wt% sodium tetraphenylborate as additive. The electrode exhibits a Nernstian response (28.7 mV decade$^{-1}$) for Pb$^{2+}$ over a wide concentration range (1.0 ${\times}$ 10$^{-1}$ to 1 ${\times}$ 10$^{-6}$ M) with a detection limit of 6.0 ${\times}$ 10$^{-7}$ M. This sensor has a short response time and can be used for at least 2 months without any divergence in potentials. The proposed electrode could be used in a pH range of 3.0-6.0 and revealed good selectivities for Pb$^{+2}$ over a wide variety of other metal ions. It was successfully applied as an indicator electrode for the potentiometric titration of lead ion with potassium chromate and for the direct determination of lead in mine.

• 대한화학회지
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• 제35권6호
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• pp.645-652
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• 1991

몇 가지 전이금속이온(Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ)) 및 후전이금속이온(Cd(Ⅱ), Hg(Ⅱ), Pb(Ⅱ))과 $N_2O_3$계 거대고리 리간드인 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacyclooctadecane 사이에 형성되는 착물의 안정도 상수를 수용액에서 전위차 적정법으로 결정하였다. 각 착물의 안정도 상수$(logK_f)$는 $25^{\circ}$C에서 Co(Ⅱ): 3.83, Ni(Ⅱ) : 4.56, Cu(Ⅱ) : 7.74, Zn(Ⅱ) : 4.98, Cd(Ⅱ) : 3.91, Hg(II) : 14.87, Pb(Ⅱ) : 6.65이었다. 전이금속착물의 안정도 순위는 Williams-Irving 서열인 Co(Ⅱ) < Ni(Ⅱ) < Cu(Ⅱ) < Zn(Ⅱ)와 일치하였고, 후전이금속착물의 안정도는 Cd(Ⅱ) < Pb(Ⅱ) < Hg(Ⅱ)이 순위이었다. 한편 메탄올 용액에서 자외-가시선이온과 리간드가 1:1인 조성을 가졌으나, Ni(Ⅱ), 착물은 1:1과 1:2 두 가지 조성을 가질 수 있음을 알았으며, 또 디메틸술폭시드 용액에서 $^1H-$와 $^{13}C-$핵자기공명스펙트럼을 분석하여 후전이금속이온 착물은 주로 리간드의 질소원자가 결합에 기여함을 알았다. Cu(Ⅱ)와 Zn(Ⅱ)이 고체착물은 원소분석, 전기전도도, 자화율 측정, 자외-가시선 및 적외선 스펙트럼분석 등으로 Cu(Ⅱ) 착물은 일그러진 팔면체, 그리고 Zn(Ⅱ) 착물은 사면체 구조를 이루고 있는 것으로 예측되었다.