• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2383-2389
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• 2008

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1349-1352
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• 2012

• Journal of the Korean Chemical Society
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• v.46 no.5
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• pp.484-488
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• 2002

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.1031-1037
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• 2006

New nickel complexes containing novel tetradentate ligands, 4,5-substituted-1,2-bis(pyridine-2-carboxamide)-benzene ligands but lacking alkyl or halide ligands in the coordination sphere have been prepared. They were activated with MMAO (modified methylaluminoxane) to be proven as efficient catalysts for the polymerization of norbornene. Both electron-donating and -withdrawing substituents on the benzene ring and polar solvents enhance the catalytic activity for olefin polymerization. Improvement in thermal stability of the complexes was observed. Some of these complexes were crystallographically determined to have square planar geometry. A plausible mechanism involving dissociation of ligands is proposed.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2138-2142
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• 2013

Two new 3D coordination complexes [Cd(3-bpcd)(pht)] (1) and [Zn(3-bpcd)(pht)] (2) [3-bpcd = N,N'-bis(pyridin-3-yl)cyclohexane-1,4-dicarboxamide, $H_2pht$ = phthalic acid] have been hydrothermally synthesized. X-ray diffraction analysis reveals that the complexes 1 and 2 represent a 4-connected diamondoid topology with a 3-fold interpenetrating feature. Moreover, the fluorescent properties of complexes 1 and 2 are studied.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.150-151
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• 2006

Perfluoroaryl boranes are widely employed as co-catalysts in olefin polymerization processes. Perfluoroaryl diboranes, possessing borane centers in close proximity, are a subclass of this family of compounds that are in theory capable of chelating neutral and anionic bases. The resulting anions are exceptionally weakly coordinating. We have prepared examples of such compounds and studied their coordination behavior with neutral Lewis bases that have the capability to bridge Lewis acid sites in an effort to delineate the kinetic and thermodynamic factors that influence bonding mode. When protic Lewis bases such as alcohols or water are reacted with diboranes, strong Bronsted acids capable of initiating cationic polymerizations under unusual conditions result.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2045-2050
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• 2007

The reactions of mercury(II) chloride with O3S2-donor macrocyclic ligands with (L1) and without (L2) dibenzosubunit afforded respective exo- (1) and endo-coordinated (2) complexes depending on the ring rigidity of the ligands. From the X-ray crystal structures and comparative NMR studies for the complexes 1 and 2, it is confirmed that the resulting species with different coordination modes exist not only in solid state but also in solution state.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.560-567
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• 2013

A series of new Iron(II) Schiff base amino acid complexes derived from the condensation of amino acid and sodium 2-hydroxybenzaldehyde-5-sulfonate have been synthesized. The complexes were characterized by elemental, electronic, IR spectral analyses and conductance measurements. The stability and solubility of the prepared complexes were determined. Two spectral methods used to determine the stoichiometry of the prepared complexes which exhibited divalent tridentate coordination and formed chelates of octahedral structures. The antibacterial activity of the prepared complexes has been tested against Bacillus cereus, Pseudomonas aeruginosa and Micrococcus bacteria. The effect of HCl on investigated complexes studied spectrophotometrically.

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1711-1713
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• 2004

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.774-776
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• 1994

Ab initio studies of simple model systems for the carboxypeptidase A active site indicate that penta-and hexa-coordinate Zn(II) complexes have comparable structural stabilities. These facile coordination structures can be responsible for the catalytic role. Although the hexa-coordinate Zn(II) complex is more stable in enthalpy than the penta-coordinate Zn(II) complex, the entropy effect makes the latter as stable as or slightly more stable in free energy than the former.