• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2546-2548
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• 2007

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1597-1600
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• 2006

The mononuclear iron complex 1, $Fe^{III}$(Hbida)Cl($H_2O$), was synthesized using a tripodal tetradentate ligand, N-(benzimidazol-2-ylmethyl)iminodiacetic acid (H3bida), which has two carboxylate groups, one benzimida- zoyl group, and one tertiary amine where it serves as a tetradentate chelating ligand for the octahedral Fe(III) ion. The four equatorial positions of the octahedral complex are occupied by two monodentate carboxylates, a benzimidazole nitrogen, and an oxygen of a water molecule. One of the axial positions is occupied by an apical nitrogen of the Hbida and the other by a chloride anion. The mononuclear octahedral complex 1 mimics the geometry of the key intermediate structure of the catalytic reaction cycle proposed for the FeSODs, which is a distorted octahedral geometry with three histidyl imidazoles, an aspartyl carboxylate, a superoxide anion, and a water molecule. The redox potential of complex 1, $E_{1/2}$ is -0.11V vs. Ag/AgCl (0.12 V vs. NHE), which is slightly lower than those reported for the most FeSODs. The magnetic susceptibility of complex 1 at room temperature is 5.83 $\mu$B which is close to that of the spin only value, 5.92 $\mu$B of high-spin d5 Fe(III).

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.1956-1962
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• 2009

The binding abilities of two multidentate tripodal amine catechol ligands, cis,cis-1,3,5-tris[(2,3-dihydroxybenzylamino) aminomethyl]cyclohexane (TMACHCAT, $L^1)\;and\;N^1,N^3,N^5$-tris(2-(2,3-dihydroxybenzylamino) ethyl)cyclohexane-1,3,5-tricarboxamide (CYCOENCAT, $L^2$) with Ga(III) and In(III) have been investigated by potentiometric and spectrophotometric methods in an aqueous medium of 0.1 M KCl at 25 ${\pm}\;1\;{^{\circ}C}.$ The ligands $L^1\;and\;L^2$ formed various monomeric species $MLH_3,\;MLH_2$, MLH and ML (M = $Ga^{+3}\;and\;In^{+3}$) and showed potential to form strong encapsulated tris(catechol) type complexes. The coordination modes, binding ability and selectivity of the ligands towards Ga(III) and In(III) have been discussed with the help of experimental evidences, and supported with molecular modeling calculations.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2466-2470
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• 2007

A new highly salicylate-selective PVC membrane electrode based on tripodal tris-thiourea derivatives, L1 and L2, as neutral carriers is described. The electrodes display an excellent potentiometric response to salicylate ions and an anti-Hofmeister selectivity sequence in the following order: Salicylate? > ClO4 ? > Benzoate? > I? >NO3? > NO2? > Maleate? > Acetate? > Lactate? > Fumarate?. It also exhibited a near-Nernstian potential in a linear range of 5.0 × 10?5 - 1.0 × 10?1 M with a detection limit of 9.0 × 10?5 mol/L and a slope of ?59.9 mV/decade at a pH of 7.0 in a saline buffer solution at 25 oC. The stability constant (log KS) of the anionsionophore complex was also determined at 25 oC by a conductometric titration in DMSO solution.

• Bulletin of the Korean Chemical Society
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• v.20 no.10
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• pp.1235-1237
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• 1999

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1790-1794
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• 2005

Fréchet-type dendritic benzyl azides were efficiently synthesized using 5-(azidomethyl)-1,3-dihydroxybenzene as an azide focal point functionalized unit by adding a generation to the existing dendron and applied for the construction of dendrimers containing 1,2,3-triazole rings as connectors via click chemistry with a tripodal acetylene core.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3904-3908
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• 2011

A new octahedral Ru(III) complex with a tripodal tetraamine ligand, tpea = tris[2-(1-pyrazoyl)ethyl]amine, has been prepared and characterized. The single crystal X-ray crystallographic study of the complex revealed that the complex has a near octahedral geometry with the tetradentate ligand and two chloride ions. Peroxidase activity was examined by observing the oxidation of 2,2'-azinobis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) with hydrogen peroxide in the presence of the complex. Amount of $ABTS^{+{\bullet}}$ generated during the reaction was monitored by UV/VIS and EPR spectroscopies. After the initiation of the peroxidase reaction, $ABTS^{+{\bullet}}$ concentration increases and then decreases after certain time, indicating that both ABTS and $ABTS^{+{\bullet}}$ are the substrates of the peroxidase activity of the Ru(III) complex.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.417-420
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• 2007

Mononuclear mixed-anions Mn complex of TPAMn(η2-NO3)(η-ClO4), where TPA is tris(2-pyridylmethyl)-amine, has been synthesized and characterized. The neutral TPAMn(η2-NO3)(η-ClO4) was obtained from the reaction between Mn(NO3)2·4H2O and [H3TPA](ClO4)3 in MeOH. X-ray crystallographic structure of mononuclear TPAMn(η2-NO3)(η-ClO4) complex showed a seven-coordinated geometry with a tripodal tetradentate TPA, a terminal perchlorate and an η2-bound nitrate.

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.406-409
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• 1997

The various cobalt(Ⅱ) complexes were synthesized and characterized using tris-(2-benzimidazolylmethyl)amine (ntb) as a ligand where the ntb plays as a tripodal tetradentate ligand to form complexes with a trigonal pyramidal geometry. The complexes have 5 and 6 coordinate cobalt(Ⅱ) ions depending on the additional ligand used. In each complex the additional ligand, chloride anion, or acetate anion occupies the "open" site trans to the apical tertiary nitrogen atom of ntb ligand. Complex 1, [Co(Ⅱ)(ntb)Cl]Cl has a trigonal bipyramidal geometry. This geometry was easily constructed using ntb as a tetradentate ligand and chloride as a monodentate ligand. The complex is isostructural to the corresponding manganese(Ⅱ) complex. Crystal data are as follows: [Co(Ⅱ)(ntb)Cl]Cl·MeOH, 1. triclinic space group P1; a=13.524(2) Å, b=14.037(2) Å, c=17.275(1) Å; α=78.798(9), β=84.159(8)°, γ=65.504(9)°; V=2929.6(6) Å3; Z=4; R1=0.0715, wR2=0.1461 for reflections of I > 2σ(I). Six coordinate complex 2 [Co(ntb)(OAc)](OAc) was synthesized using ntb as a tetradentate ligand and acetate as a bidentate chelating ligand.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.658-660
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• 2005