• 대한화학회지
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• 제36권2호
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• pp.212-217
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• 1992

수용액내에서 gadolinium-벤조산 착물형성 반응의 열역학적 함수값들을 이온상수 0.1M $NaClO_4$, $25^{\circ}C$ 조건하에서 구하였다. gadolinium-벤조산 착물의 안정도는 여분의 엔트로피 효과에 기인하는 것으로 판단되며, 벤조산 리간드의 경우 한 자리 리간드에 비해 높은 안정도 상수값을 나타내었다. 이러한 높은 안정도는 리간드내의 벤젠고리의 공액효과로 예측되었다. 합성된 Ga$(ben)_3$의 고체 IR스펙트럼 결과, 벤조산 리간드가 두 자리 리간드로 작용하여 킬레이트를 형성하였으며, 80${\sim}$300K 온도 범위에서의 자화율 데이터는 Curie-Weiss 법칙에 잘 적용됨을 알 수 있었다.

• 대한화학회지
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• 제51권4호
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• pp.339-345
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• 2007

Urea는 높은 온도(60~80 °C)의 수용액 상태에서 PtCl2, H2[PtCl6]·6H2O, H2[IrCl6] Ni(CH3CO2)2 와 반응해서 각각 (1)[PtCl2(Urea)]·2H2O, (2)(NH4)2[PtCl6], (3)(NH4)2[IrCl6]·H2O, (4)[Ni2(OH)2(NCO)2(H2O)2]의 complexes를 생성 한다. complexe 1에서 urea는 중성 bidentate 리간드로써 Pt(II)와 배위한다. complexe 2,3,4에서는 높은 온도에서 반 응하는 동안 배위 urea분자들이 분해되고 다양한 반응생성물들을 얻을 수 있다. 모든 complexes은 각각 적당한 수득률 로 dark green(1) yellow(2), pale brown (3) faint green(4)의 침전물로 분리된다. 반응생성물은 열분석, IR, 1H and 13C NMR spectra에 의해 측정 되었다. 이 complexes의 구성을 설명하는 일반적인 매카니즘이 제시되었다.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.2917-2924
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• 2012

Four novel metal-organic complexes $[Cd_2(IP)_2(TBZ)_2(H_2O)_2]{\cdot}(H_2O)$ (1), $[Zn_4(IP)_4(TBZ)_4]{\cdot}2(H_2O)$ (2), $[Zn_2(BTC)(TBZ)_2(CO_2H)]$ (3), [Co(PDC)(TBZ)] (4) (where IP = isophthalate; TBZ = thiabendazole; BTC = 1,3,5-benzenetricarboxylate; PDC = pyridine-3,4-dicarboxylate) have been prepared and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. X-ray structure analysis reveals that 1, 2, and 3 are one-dimensional chain polymers, while 4 is a two-dimensional network polymer. The TBZ acts as a typical chelating ligand coordinated to the metal center in all complexes. The 1D chain architecture of 1 is constructed from isophthalates and cadmium atoms. A simultaneous presence of chelating, monodentate and bidentate coordination modes of IP ligands is observed in complex 2. In complex 3, the 16-membered rings are alternately arranged forming an infinite 1D double-chain structure. The 2D skeleton of 4 is formed by cobalt ions as nodes and PDC dianions as spacers, through coordination bonds. The hydrogen bonds and ${\pi}-{\pi}$ stacking play important roles in affecting the final structure where complexes 1 and 3 have 2D supramolecular networks, while complexes 2 and 4 have 3D supramolecular architectures.

• Bulletin of the Korean Chemical Society
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• 제26권8호
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• pp.1197-1202
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• 2005

The Ln(III) complexes with picrate ligand, $[Sm(Pic)_2(H_2O)_6]Pic{\cdot}6H_2O$, 1, and $[Ho(Pic)(H_2O)_7](Pic)_2{\cdot}3H_2O$, 2, have been synthesized and their crystal structures are analyzed by X-ray diffraction methods. Complex 1, crystallizes in the monoclinic $P2_1/n$ space group and complex 2 in the triclinic P-1 space group. In complex 1, two picrate ligands coordinate to the Sm(III) ion, one of them in the bidentate fashion. There are one picrate anion and six water molecules in the crystal lattice. The nine-coordinated Sm(III) ion forms a slightly distorted tricapped trigonal prism. In complex 2, only one picrate ligand coordinates to the metal ion as a monodentate. There are two picrate anions and three water molecules in the crystal lattice. The eight-coordinated Ho(III) ion forms a distorted bicapped trigonal prism. Based on the results of the TG-DTG and DSC thermal analysis, it was analyzed that the lanthanide picrate complexes 1 and 2 are thermally decomposed in three distinctive stages, the dehydration, the picrate decomposition, and the formation of the metal oxide.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1553-1558
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• 2009

A series of Eu(III) complexes with various neutral ligands (2,2’:6’,2"-terpyridine (T), diglyme (D), 1N-(2-dimethylamino) ethyl)-1N, 2N, 2N-trimethylethane-1,2-diamine (PT), di-(2-picolyl)-amine derivative (HT), and multidentate terpyridine derivative (DT)) were synthesized to investigate the effect of coordination environment on the sensitized luminescence of Eu(III) complexes. The nine coordination sites of the $Eu^{3+}$ ion are occupied by three bidentate carboxylate moieties and one neutral ligand. The highest emission intensity is obtained for $Eu^{3+}$- $[NA]_3$ (PT), due to the difference in energy transfer efficiency and symmetry of the first coordination sphere of $Eu^{3+}$ ion. But, the lowest emission intensity is obtained for $Eu^{3+}$-$[NA]_3$(T). Terpyridine may not play an important role antenna for photosensitizing $Eu^{3+}$ ion. It could be attributed to the weak spectral overlap integral J value between its phosphorescence band and $Eu^{3+}$ion absorption band. Therefore, different coordination environment of $Ln^{3+}$ ion play an important role in providing sensitization of lanthanide ion emission.

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.990-996
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• 1994

New ferrocene-based chelate amines, $Fe[C_5H_4CH(Me)NMe_2]_2\;(3), \;Fe[C_5H-3(CH(Me)NMe_2)(PPh_2)-1,2]_2\;(4),\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(CN)NMe_2-1,2)\;(6),\;and\;(C_5H_5)Fe(C_5H_3(CH_2NMe_2)(CH(Me)NMe_2-1,2)$ (7) have been prepared. The reaction and the coordination chemistry of 4 and other related compounds (S,R)-(1-N,N-dimethylaminoethyl)-2-dicyclohexylphosphino)ferrocene (CPFA) and 1,1'-bis-(diphenylphosphino)ferrocene (BPPF) with $Rh_2(OAc)_4(MeOH)_2$ were investigated. The reaction of the chiral ligand (S,R)-CPFA forms a complex of the type (${\eta}^1$-(S,R)-CPFA-P)$_2Rh_2(OAc)_4$ (8) in which the ligand is coordinated to both rhodium centers in a monodentate fashion through phosphorus. In contrast, the bisphosphine analogues such as BPPF and 4 afford chelate complexes of the type (${\eta}^2-PP)Rh_2(OAc)_4$ (9 & 10) where both ligands act as a chelate bidentate to a single rhodium atom. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of 8 was determined by X-ray crystallography. Crystals are monoclinic, space group C2 (No. 5), with a=26.389 (3), b=12.942 (1), c=11.825 (1) A, ${\beta}$=111.22(1)$^{\circ}$, V=3964.7 (8) $A^3$, Z=4, and $D_{calc}$=1.58 g $cm^{-3}$. Two Rh(II) centers are bridged by four $AcO^-$ groups in the ${\eta}^1$ : ${\eta}^1$ mode across a Rh-Rh single bond, and octahedral coordination at Rh(1) and Rh(1') is completed by axially coordinating (S,R)-CPFA and a briding $AcO^-$, respectively.

• Bulletin of the Korean Chemical Society
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• 제14권2호
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• pp.266-271
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• 1993

The reaction of $(CO_5$)M=C(OMe)Tol (M=Cr, Mo, W and $Tol=p-C_6H_4Me)$ and $BBr_3$ followed by treatment with tetramethylethylenediamine (TMEDA) yields a mixture of two diastereomers, trans, $cis-Br(CO)_2(tmeda)M{\equiv}$CTol [M=Cr(1a), Mo(2a), W(3a)] and cis, $trans-Br(CO)_2(tmeda)M{\equiv}$CTol [M=Cr(1b), Mo(2b), W(3b)], respectively. These compounds have been isolated as crystalline solids and characterized by spectroscopic (infrared, mass, $^1H$ and $^{13}C-NMR)$ data. The trans, cis-Br(CO)2(tmeda)Cr${\equiv}$CTol (1a), has been examine via a single crystal X-ray diffraction study : $BrCrO_2N_2C_{16}H_{23}$, Mr=407.27, triclinic, $P{\bar{1}},\;a=12.792(2),\;b=13.400(5),\;c= 11.645(4)\;{\AA},\;{\alpha}=101.26(2)^{\circ},\;{\beta}=103.04(2)^{\circ},\;{\gamma}=91.88(2)^{\circ},\;{\nu}=1907(1){\AA}^3,\;Z=2,\;{\rho}(calcd)=1.418\;gcm^{-3},\;{\lambda}(MoK{\alpha})=0.71069\;{\AA},\;{\mu}=26.25 cm^{-1},\;F(000)=831.97,\;T=295K,\;R=0.0977$ for 1332 significant reflections $[F_0>5{\sigma}(F_0)]$. There are two essentially equivalent molecules in the crystallographic asymmetric unit. Each molecule is octahedral with the bromide ligand trans to the alkylidyne carbon, the two cis-carbonyl ligands, and the bidentate TMEDA ligand.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2774-2780
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• 2013

Two new isostructural dinuclear complexes, $Ln_2(4-cpa)_6(bpy)_2$ (Ln = Eu (1); Tb (2), 4-cpa = 4-chlorophenylacetate, bpy = 2,2'-bipyridine), have been hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. The lanthanide ions are bridged by two bidentate and two terdentate carboxylate groups to give centrosymmetric dimers with $Ln{\cdots}Ln$ separations of 3.967(2) and 3.956(3) ${\AA}$, respectively. Each metal atom is nine-coordinate and exhibits a distorted tricapped trigonal prismatic geometry. Three-dimensional fluorescence spectra show that both 1 and 2 emit bright red and green luminescence at room temperature, with long lifetimes of up to 0.369 ms (at 614 nm) and 0.432 ms (at 543 nm), respectively. Moreover, poor luminescence efficiency has been noted for complex 2. The 4-Hcpa ligand and complexes 1-2 have been screened for their phytogrowth-inhibitory activities against Brassica napus L. and Echinochloa crusgalli L., and the results are compared with the activity of quizalofop-P-ethyl.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3255-3260
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• 2011

Two novel binuclear metal-organic coordination complexes $[Cd_2(L)_2(bpy)_2(H_2O)_2]{\cdot}6H_2O$ (1), $[Cd_2(L)_2(phen)_2-(H_2O)_2]{\cdot}2H_2O$ (2) (where L = 2-methylquinoline-3,4-dicarboxylate dianion, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline) have been synthesized under hydrothermal conditions and characterized by single crystal Xray diffraction, spectral method (IR), elemental analysis and thermal gravimetric analysis (TGA). Both 1 and 2 consist of two Cd(II) atoms bridged by two monoatomic bridging carboxylate groups from two L ligands, and the second carboxylate group of each L is monodentately coordinated to Cd(II), creating a sevenmembered chelating ring. The coordination at each metal nucleus is completed by a water molecule and a chelating bidentate molecule. The 3D structures of the complexes are stabilized by ${\pi}-{\pi}$ stacking interactions and hydrogen-bonds.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1603-1606
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• 2009

A new 1D oxalato bridged compound Ni(en)(ox)-2$H_2$O, (ox = oxalate; en = ethylenediamine) has been hydrothermally synthesized and characterized by single crystal X-ray diffraction, IR spectrum, TG analysis, and magnetic measurements. In the structure the Ni atoms are coordinated with four oxygen atoms in two oxalate ions and two nitrogen atoms in one ethylenediamine molecule. The oxalate anion acts as a bis-bidentate ligand bridging Ni atoms in cis-configuration. This completes the infinite zigzag neutral chain, [Ni(en)(ox)]. The interchain space is filled by water molecules that link the chains through a network of hydrogen bonds. Thermal variance of the magnetic susceptibility shows a broad maximum around 50 K characteristic of one-dimensional antiferromagnetic coupling. The theoretical fit of the data for T > 20 K led to the nearest neighbor spin interaction J = -43 K and g = 2.25. The rapid decrease in susceptibility below 20 K indicate this compound to be a likely Haldane gap candidate material with S = 1.