• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.804-807
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• 1999

New copper complexes with a ligand, L(L=N,N'-cyclohexane bis(ferrocenylmethylene)amine) which was obtained from ferrocene carboxaldehyde and 1,2-diaminocyclohexane with a mole ratio of 2:1, were prepared and characterized. Those were adapted to asymmetric catalysis. The copper(II) complexes do not work in cyclopropanation of styrene and ethyl diazoacetate but copper(I) complex catalyzes. The Cu(I)LOTf (OTf=trifluorometanesulfonate) shows a good regioselectivity giving high trans to cis ratio of up to 80:20.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1965-1968
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• 2005

Extended H$\ddot{u}$ckel molecular calculations have been used to analyze how the magnitude of exchange coupling is influenced by the structural distortions in a series of dinuclear six-coordinate copper(II) complexes bridged by the planar bis-bidentate oxalate anion. Copper(II) ions have distorted octahedral surroundings, one being axially elongated and the other compressed. The magnetic interaction is strong in the former complexes and very weak in the latter. This is interpreted as resulting from a switching of magnetic spin orbitals due to the structural distortions (bond elongation or compression) of the copper sites.

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.594-598
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• 1993

The protonation constants of the 14-membered tetraaza macrocycles A(3,14-dimethyl-2,6,13,17-tetraazatricyclo$[l6.4.0^{1,18}.0^{7,12}]$docosane) and B(2,3,6,13,14,17-hexamethyl-2,6,13,17-tetraazatric yclo-[l6.4.$0^{1,18}.0^{7,12}$]docosane) were measured by potentiometry. The formation constants of each of these ligands with copper(II) and nickel(II) were determined by an out-of-cell spectrophotometric method. The results indicate that the per-N-methylated macrocycle B exhibits much higher selectivity for complex formation with copper(II) over nickel(II) ion than A and other related 14-membered tetraaza macrocycles. The effects of the N-and C-substituents on the basicity and the metal ion selectivity of the ligands are discussed. The synthesis and properties of copper(II) and nickel(II) complexes of B are also described.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.577-580
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• 2006

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1973-1976
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• 2004

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.18-351
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• 1999

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.709-719
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• 1992

We synthesized the binuclear tetradentate Schiff base cobalt(II), nickel(II) and copper(II) complexes such as [Co(II)_2(TSBP)(L)_4], [Ni(II)_2(TSBP)(II)_4] and [Cu(II)_2(TSBP)] (TSBP: 3,3',4,4'-tetra(salicylideneimino)-1,1'-biphenyl, L: Py, DMSO and DMF). We identified the binucleated structure of these complexes by elemental analysis, IR-spectrum, UV-visible spectrum, T.G.A. and D.S.C. According to the results for cyclic voltammogram and differential pulse polarogram of 1 mM complexes in nonaqueous solvents included 0.1M TEAP-L (L; Py, DMSO and DMF) as supporting electrolyte, it was found that diffusionally controlled redox processes of four steps through with one electron for binucleated Schiff base Cobalt(II) complex was Co(III)_2 {^\longrightarrow \\_\longleftarrow^e^-}Co(III)Co(II)_2{^\longrightarrow \\_\longleftarrow^e^-}Co(II){^\longrightarrow \\_\longleftarrow^e^-}Co(I){^\longrightarrow \\_\longleftarrow^e^-}Co(I)_2 and two steps with one electron for Nickel(II) and Copper(II) complexes were M(II)_2 {^\longrightarrow \\_\longleftarrow^e^-}M(I)M(I){^\longrightarrow \\_\longleftarrow^e^-}M(I)_2 (M; Ni and Cu) in nonaqueous solvents.

• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.397-401
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• 2009

The complexes of $C_2-\;and\;C_6$-dihydroceramides with transition metal ions have been investigated by using Electrospray ionization-tandem mass spectrometry (ESI-MS/MS). The formation and fragmentation pathways of several doubly charged cluster ions as well as singly charged cluster ions of $C_2-\;and\;C_6$-dihydroceramides with transition metal ions have studied by ESI-MS/MS in the positive mode. Under ESI conditions, dihydroceramides form singly and doubly charged complexes with transition metal ions $(Mn^{2+},\;Fe^{2+},\;Co^{2+},\;Ni^{2+},\;and\;Zn^{2+}\;except\;Cu^{2+})$ with the compositions of $[DHCer+M+2H^2O-H]^+,\;[2DHCer+M+2H2O-H]^+,\;[3DHCer+M+2H2O-H]^+,\;[2DHCer+M]^{2+},\;[3DHCer+M]^{2+},\;[4DHCer+M]^{2+},\;[5DHCer+M]^{2+},\;and\;[6DHCer+M]^{2+}\;(DHCer\;=\;C_2-\;or\;C_6$-dihydroceramide, M = transition metal ion). The different complexation behavior of copper is responsible for relatively lower affinity of dihydroceramides to copper compared to those of other transition metals. It is also found that in the mass spectrum of the dihydroceramide complexes with copper(II), [2DHCer+Cu-H]$^+$ was observed with considerable intensity as well as [2DHCer+Cu+2$H_2O-H]^+$ due to its different geometry from those of other metals.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.562-566
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• 2008

Reaction of AgNO3 with triethanolaminetriisonicotinate (L) produces 1 D coordination polymer of [Ag3(L)2](NO3)3 and the same treatment of Cu(NO3)2 with L gives 1D coordination polymer of [Cu(L)2](NO3)2. The nonrigid triethanolaminetriisonicotinate acts as a m 3-bridged tridentate for [Ag3(L)2](NO3)3 and a m 2-bridged bidentate for [Cu(L)2](NO3)2 to produce unusual motifs. The NO3- anions can be smoothly exchanged by PF6- anions in an aqueous suspension without destruction of the skeletal structure.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2701-2704
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• 2010

This work shows that both L2 and L3 bearing two and four N-$(CH_2)_2OCH_3$ groups, respectively, can be prepared selectively by the reaction of $L^1$ with 1-bromo-2-methoxyethane. The di-N-substituted macrocycle $L^2$ readily forms its copper(II) and nickel(II) complexes. The N-$(CH_2)_2OCH_3$ groups in $[CuL^2]^{2+}$ are coordinated to the metal ion, whereas those in $[NiL^2]^{2+}$ are not involved in coordination. Interestingly, $L^3$ reacts with $Cu^{2+}$ ion to form $[Cu(HL^3)]^{3+}$, in which one tertiary amino group is not involved in coordination.