• 분석과학
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• 제15권3호
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• pp.317-320
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• 2002

The layer structure of the title compound, $[Ni(en)_2(H_2O)_2](CH_3C_6H_4SO_3)_2(H_2O)$ (en = ethylenediamine), consists of discrete cations, anions, and solvate water molecules linked by a hydrogen bonding network. The central Ni atom of the cation layer has a slightly distorted octahedral coordination geometry with the ethylenediamine ligands functioning as a N,N'-bidentate and the water ligands bonding through oxygen in a trans arrangement. The p-toluenesulfonate of the anion layer has an alternate sulfonate group directed toward opposite side of the cation layer. This layer structure is stabilized by a hydrogen bond involving the O atoms of the sulfonate, the water ligand, solvate water molecule, and the N atoms of the ethylenediamine.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.1017-1021
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• 2011

Two new benzimidazolyl-containing complexes have been synthesized by reactions of $Cu^{II}$ salts and 1,2-bis(benzimidazolyl) benzene ($H_2bbbz$) with two different dicarboxylate ligands. When phthalate acid ($H_2pt$) was employed as secondary ligand, a 0D molecular complex Cu$(H_2bbbz)(pt){\cdot}(H_2pt)$ (1)was furnished and when the secondary ligand was instead by a linear bridging ligand of terephthalic acid ($H_2tp$) a 1D zipper-like coordination polymer $[Cu(H_2bbbz)(tp){\cdot}2(C_2H_5OH){\cdot}H_2O]_n$ (2) was obtained, suggesting the structure-direction effect of the secondary dicarbxylate ligand. The preliminary investigation on the spectral properties of the complexes was also presented.

• Bulletin of the Korean Chemical Society
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• 제15권8호
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• pp.673-679
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• 1994

$^1H$ NMR spectra of imidazole, 2-and 4(5)-methylimidazole, histamine, L-histidine, L-histidine methyl ester, N${\alpha}$-acetyl-L-histidine, and L-carnosine coordinated to the paramagnetic undecatungstocobalto(II)silicate ($SiW_{11}Co$) and undecatungstonickelo(II)silicate ($SiW_{11}Ni$) anions are reported. For these complexes the ligand exchange is slow on the NMR time scale and the pure resonance lines of the free ligand and the complexes have been observed separately at room temperature. Two different complexes are formed, depending upon which nitrogen atom of the imidazole ring is coordinated to the cobalt or nickel ion of $SiW_{11}M$. Thus the NMR spectrum of a $D_2O$ solution containing a ligand and $SiW_{11}M$ consists of three sets of lines originating from the free ligand and two complexes. All NMR lines of the $SiW_{11}Co$ complexes have been assigned unequivocally using the saturation transfer technique. The temperature dependence of some spectra are also reported. The NMR spectra of some complexes show that the internal rotation of the substituent on the imidazole ring is hampered by the heteropolyanion moiety even at room temperature.

• Bulletin of the Korean Chemical Society
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• 제18권10호
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• pp.1050-1052
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• 1997

The complexes M(CO)4-1,2-(PPh2)2-1,2-C2B10H10 (M=Cr 2a, Mo 2b, W 2c) have been prepared in good yields from readily available bis-diphenylphosphino-o-carboranyl ligand, closo-1,2-(PPh2)2-1,2-C2B10H10 (1), by direct reaction with Group Ⅵ metal carbonyls. The infrared spectra of the complexes indicate that there is an octahedral disposition of chelate bis-diphenylphosphino-o-carboranyl ligand around the metal atom. The crystal structure of 2a was determined by X-ray diffraction. Complex 2a crystallizes in the monoclinic space group P21/n with cell parameters a = 12.2360(7), b = 17.156(1), c = 16.2040(6) Å, V = 3354.1(3) Å3, and Z =4. Of the reflections measured a total of 2514 unique reflections with F2 > 3σ(F2) was used during subsequent structure refinement. Refinement converged to R1 = 0.066 and R2 = 0.071. Structural studies showed that the chromium atom had a slightly distorted pseudo-octahedral configuration about the metal center with two phosphine groups of o-carborane occupying the equatorial plane cis-orientation to each other. These metal carbonyl complexes are rapidly converted to the corresponding metal carbene complexes, [(CO)3M=C(OCH3)(CH3)]-1,2-(PPh2)2-1,2-C2B10H10 (M= Cr 3a, Mo 3b, W 3c), via alkylation with methyllithium followed by O-methylation with CF3SO3CH3.

• Bulletin of the Korean Chemical Society
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• 제17권12호
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• pp.1127-1131
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• 1996

[FeⅡ2(N-Et-HPTB)Cl2]BPh4(1), where N-Et-HPTB is the anion of N,N,N',N'-tetrakis(N-ethyl-2-benzimidazolylmethyl)-2-hydroxy-l,3-diaminopropane, has been synthesized to model dioxygen binding to the diferrous centers of proteins. 1 has a singly bridged structure with a μ-alkoxo of N-Et-HPTB and contains two five-coordinate iron(Ⅱ) centers with two chloride ligands as exogenous ligands. 1 exhibits an electronic spectrum with a λmax at 336 nm in acetone. 1 in acetone exhibits no EPR signal at 4 K, indicating diiron(Ⅱ) centers are antiferromagnetically coupled. Exposure of acetone solution of 1 to O2 at -90 ℃ affords an intense blue color intermediate showing a broad band at 586 nm. This absorption maximum of the dioxygen adduct(1/O2) was found in the same region of μ-l,2-peroxo diiron(Ⅲ) intermediates in the related complexes with pendant pyridine or benzimidazole ligand systems. However, this blue intermediate exhibits EPR signals at g = 1.93, 1.76, and 1.59 at 4 K. These g values are characteristic of S = 1/2 system derived from an antiferromagnetically coupled high-spin Fe(Ⅱ)Fe(Ⅲ) units. 1 is the unique example of a (μ-alkoxo)diferrous complex which can bind dioxygen and form a metastable mixed-valence intermediate. At ambient temperature, most of 1/O2 intermediate decays to form a diamagnetic species. It suggests that the dacay reaction of the intermediate might be bimolecular, implying the formation of mixed-valence tetranuclear species in transition state.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4197-4200
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• 2012

• 대한화학회지
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• 제33권4호
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• pp.366-370
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• 1989

새로운 거대고리 리간드 1,15,18-triaza-3,4 : 12,13-dibenzo-5,8,11-trioxa-cycloeicosane(NdienOdien$H_4$=$N_3O_3$)를 합성하여 $25^{\circ}C$ 95% 메탄올 용액에서 전위차계를 이용하여 양성자 첨가반응의 평형상수를 구한 결과 log $K_1$ ; log $K_2$ ; log $K_3$는 9.1; 8.1; 3.6이었다. 또한 위의 리간드와 이미 합성된 리간드 1,12,15-triaza-3,4;9,10-dibenzo-5,8-dioxa-cycloheptadecane(NdienOen$H_4$=$N_3O_2$)를 각각 Ni(II), Cu(II)의 금속이온과의 착물을 합성하여 수용액에서 산을 가해 착물의 산해리반응 속도 상수를 여러온도에서 분광광도법으로 측정하였다. 또한 활성화에너지($E_a$)와 활성화파라메타 ${\Delta}H^{\neq}$, ${\Delta}S^{\neq}$를 구하였다. 그리고 이들의 자료로부터 이 반응계의 타당한 해리메카니즘을 제안하였다.

• 대한화학회지
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• 제37권6호
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• pp.612-617
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• 1993

VC$l_3$과 N, P, O 주개 리간드를 반응시켜 새로운 바나듐(Ⅲ) 착물을 합성하였으며 원소분석과 적외선, 핵자기 공명 및 전자 흡수스펙트럼 등을 이용하여 그 특성을 조사하였다. 사용한 리간드는 3,5-Lutidine, 1,2-phenylenediamine, 8-hydroxyquinoline, 9,10-phenanthrenequinone, triphenylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane 과 1,1'-bis(diphenylphosphino)ferrocene이다. 합성된 착물의 V-Cl 신축진동이 298~367 c$m^{-1}$에서 나타나므로 팔면체 구조로 추정된다. V-X(X=N, P, O) 신축진동이 200~600 cm-1에서 각각 관측되므로 바나듐에 리간드가 배위도니 것을 알 수 있다. Acetonitile의 C≡N 신축진동은 자유리간드(2260 cm-1)보다 약 70 c$m^{-1}$ 증가한 위치에서 나타나며, 또한 C≡N 굽힘진동도 자유리간드(377 c$m^{-1}$)보다 약 60 c$m^{-1}$ 증가한 위치에서 나타난다. 이러한 결과에 따라 [VC$l_3$(L$_2$)MeCN] 및 [VC$l_3$(L-L)MeCN]와 같은 팔면체 구조의 바나듐(Ⅲ) 착물임을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제16권12호
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• pp.1176-1179
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• 1995

1H NMR spectra of pyridine, α-, β-, and γ-picoline coordinated to the paramagnetic heteropolyanion [Ni3(PW9O34)2]12- (P2Ni3) are reported. NMR lines are assigned to [Ni3(ptl)n(PW9O34)2]12- (n=1, 2 or 3; ptl=pyridine-type ligand) on the basis of their [P2Ni3]/[ptl] dependence. The formation constants for γ-picoline complexes at 25 ℃ are K1=80, K2=610, and K3=190 L mol-1. The monopicoline complex has greater affinity for γ-picoline than P2Ni3. A degradation product, [Ni2(WO2)(PW9O34)2]12-, was also identified at low pH by measuring the NMR spectrum of pyridine coordinated to it. The isotropic NMR shifts come mainly from the contact interaction due to σ-electron delocalization.

• 대한화학회지
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• 제29권5호
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• pp.516-521
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• 1985

한자리 리간드로써 암민, 에틸렌디아민, 트리메틸렌디아민 등을 포함하는 ethylenediamine-triacetatocobalt (III) 착물을 합성하고, Dowex 50W-X8, 수소이온형 양이온 교환수지를 사용하여 각각 한 종류의 이성질체를 분리하였으며, 원소분석, pH적정, 적외선 분광법, 핵자기공명 및 전자흡수스펙트럼으로 가능한 기하이성질체중에서 cis-equatorial형이라고 추정하였다. 여러자리 리간드를 동시에 포함하는 meridional 형의 $[CoN_3O_3]$계에서 나타난 제 1흡수띠는 크게 분열된 양상을 보여주었고, 에틸렌디아민, 트리메틸렌디아민 등이 코발트(III) 이온에 한자리 리간드로 배위되었다는 사실도 확인하게 되었다.