Abstract |
2-hydroxy-3-hydroxymethy1-5-methylbenzaldehyde(HHMMB)와 ethylenediamine 혹은 1,3-dia-minopropane의 축합반응에 의해 6-배위 칸막이 리간드, H4L[A]와 H4L[B]}를 각각 얻은 후에 거대비고리 리간드 착물, Cu(H2L[A])·H2O, Cu(H2L[B])·H2O, CuFe(L[A](NO3)·4H2O, CuFe(L[B])(NO3)·4H2O,[CuGd(H2L[A])(NO3)2](NO3)·2CH3OH,[CuGd(H2L[B])(NO3)2](NO3)·2CH3OH를 합성하였다.2,6-diformyl-p-clesol (DFPC)로부터 합성한 Ln-거대고리([20]DOTA)착물,[Ln([20]DOTA)(NO3)(H2O)](NO3)2·xH2O{Ln(III)=Pr, Sm, Gd, Dy}를 methanol 용매에 2일 정도 정치함으로써 [Ln([20]DOTA)(NO3)(CH3OH)]2+을 얻을 수 있다. 이 lanthanide-[20]DOTA착물에서 배위된 CH3OH이 주게원자가 N 혹은 O인 두자리 보조리간드, La(=o-phenylenediamine,1,10-phenanthroline, ethylenediamine,oxalic acid, malonic acid, acethyl-acetone에 의해 치환될 때 평형상수(K)를 25℃ μ=0.lM NaCㅣO4 에서 분광학적 방법으로 결정하였다. 보조리간드의 pKa는 o-Phenylenediamine < 1,10-ptlenanthroline < ehylenediamine,oxalic acid < malonic acid < acethylacetone이며, 이때 평형상수, K는 ethylenediamine < 1,10-phenanthroline < o-phenylenediamine,acethylacetone < malonic acid < oxalic acid 경향으로 변하였다. Macroacyclic transition metal complexes such as Cu(H2L[A])·H2O, Cu(H2L[B])·H2O,CuFe(L[A])(NO3)·4H2O, CuFe(L[B])(NO3)·4H2O,[CuGd(H2L[A])(NO3)2] (NO3)·2CH3OH,[CuGd(H2L[B])(NO3)2](NO3)·2CH3OH were prepared from the corresponding hexadentate compartmental ligands, H4L[A] and H4L[B], which were obtained by the condensation of 2-hydroxy-3-hydroxymethy1-5-methyIbenzaldehyde(HHNNB) and ethylenediamine or l,3-diaminopropane. Ln-macrocyclic([20]DOTA) complexes,[Ln([20] DOTA)(NO3)(H2O)](NO3)2·xH2O{Ln(III)=Pr, Sm, Gd, Dy, which had been synthesized from 2,6-diformyl-p-cresol(DFPC), was placed in methanol for 2 days, and [Ln([20] DOTA)(NO3)(CH3OH)]2+ was formed The equilibrium constants (k) for the substitution of coordinated CH3OH in the Ln-[20]DOTA complexes by various bidentate auxiliary ligands, La(=o-phenylenediamine,1,10-phenanthroline, ethylenediamine,oxalicacid, malonic acid, acethylacetone) were determined by spectroscopic method at 25oC and 0.lM NaClO4.The pKa of auxiliary ligands is in the order of o-phenylenediamine < 1,10-phenanthroline < ethylene-diamine, oxalic acid < malonic acid < acethylacetone. However, the equilibrium constant(K) has shown thetrend of ethyleneiamine < 1,1O-phenanthroline < o-phenylenediamine, acethylacetone < malonic acid < oxalic acid. |
