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1

Synthesis and Magnetic Studies of [Cu3IILnIII] Heterotetranuclear Complexes with N,N’- Bis(3-amino-2,2-dimethylpropyl)oxamidocopper (II)

100%

Li Y. T. , Yan C. W. , Wang H. L.

Polish Journal of Chemistry

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2001

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tom Vol. 75, nr 12

1817-1824

EN

Eleven newoxamido-bridged Cu"Ln"'-type (Ln = La, Ce, Pr.Nd, Sm, Eu, Gd, Tb, Ho, Er, Yb) heterotetranuclear complexes, namely Cu3(Me2Oxpn)3Ln(NOj)3, where Me2oxpn denotesN,N'-bis(3-amino-2,2-dimethylpropyl)oxamido dianion, have been synthesized and characterized by elemental analyses, molar conducti vity measurements, and spectro-scopic (IR, UV, ESR) studies. Cryomagnetic measurements (4.2~300 K) and studies of Cu3(Me2oxpn)jGd(NO3)3 complex have revealed that the gadolinium(Ill) and copper(II) ions arę ferromagnetically coupled with the exchang_e integraj J = +3.88 cm'1, on the basis of the spin Hamiltonian operator [H = -2J(S, o S" + S: o S" + Sj o S,>)].

2

Synthesis, Characterization and Magnetic Properties of mi-Oxalato-Bridged Binuclear Iron(III) Complexes

100%

Li Y. T. , Yan C. W. , Zhang Y. H.

Polish Journal of Chemistry

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2001

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tom Vol. 75, nr 12

1825-1831

EN

Four new oxalato-bridged iron(FII)-iron(III) binuclear complexes have been synthesized and characterized, namely [Fe2(ox)jL2], where ox represents the oxalato dianions; L stands for 2,9-dimethyl-1,10-phenanthroline (Mc2-phen); 4,7-diphenyl-1,10-phenanthroline o:'"o (Ph2-phen); diaminoethane (en) or l ,3-diaminopropane (pn), respectively. Based on elemental analyses, molar conductivity and magnetic moment (at room-temperature) measurements, IR and electronic spectral studies, these complexes arę proposed to have extended ox-bridged structure consisting of two iron(IIl) ions, each in an octahedral environment. The variab!e-teinperature susceptibilities of [Fe2(ox)](Me2-phen)2] (1) and [Fe2(ox))(Ph2-phen)j] (2) complexes were measured and studied in the 4.2-300 K range. The magnetic coupling parameter is consistent with an antiferromagnetic exchange in-teraction between the iron(FFI) ions through the oxalato-bridged in both complexes (1) and (2). Based on the spin Hamiltonian operator, H = 2JS i -S 2, the exchange parameters (J) were evaluated as -4.85 cm"' for (I) and J = -6.39 crrf' for (2).

3

Synthesis , characterization and magnetic studies of my-oxamido heterodinuclear copper(II)-iron(II) complexes

100%

Li Y. T. , Yan C. W. , Kong X. H.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 9

2052-2059

EN

Six new my-oxamido heterodinuclear complexes, [Cu(Me2oxpn)Fe(L)2]SO4, have been synthesized from the planar monomeric fragment [Cu(Me2oxpn)], where Me2oxpn denotes N,N'-bis(3-amino-2,2-dimethylpropyl)oxamido dianion and L represents 1,10-phenanthroline(phen);5-nitro-1,10-phenanthroline (NO2-phen); 5-chloro-1,10-phenanthroline (Cl-phen); 5-bromo-1,10-phenanthroline (Br-phen); 5-methyl-1,10-phenanthroline (Me-phen) and 2,2'-bipyridine (bpy). Based on the elemental analyses, spectroscopic studies, magnetic moments (at room temperature) and molar conductivity measurements, extended oxamido-bridges structures consisting of a copper(II) and an iron(II) ions, which have a square planar environmental and an octahedral environment, respectively, are proposed for these complexes. The [Cu(Me2oxpn)Fe(bpy)2]SO4 (1) and [Cu(Me2oxpn)Fe(phen)2]SO4 (2) complexes have been characterized by variable temperature magnetic susceptibility (4.2-300 K) and the oberved data were least-squares fitted to the susceptibility equation derived from the spin Hamiltonian including single- ion zero-field interaction for the iron(II) ion, H=-2JS1 x S2 - DS(2)-Zl, giving the exchange integrals J=-15.8 cm(-1) for (1) and J=-17.6 cm(-1) for (2). These results indicated that the spin coupling between the adsjacent copper(II) and iron(II) ions through oxamido-bridge in both complexex (1) and (2) is antiferromagnetic.

4

Synthesis, characterization and magnetism of tetracarboxylato-bridges dinuclear nickel(II) complexes

100%

Yan C. W. , Li Y. T. , Sun H. T. , Liao D. Z.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 9

2045-2051

EN

Five new tetracarboxylato-bridges dinuclear nickel(II) complexes of the formula [Ni2(PMTA)L4], where L denotes 4,7-diphenyl-1,10-phenanthroline (Ph2-phen); 2,9-dimethyl-1,10-phenanthroline (Me2-phen); diaminoethane (en); 1,3-diaminopropane (pn) and 1,2-diaminopropane (ap); and PMTA represents the tetraanion of pyromellitic acid, have been synthesized and characterized by elemental analyses, molar conductivity and room temperature magnetic moment measurements, and by spectroscopy. It is proposed that these complexes have PMTA-bridged structures and consist of two nickel(II) ions in a distorted octahedral environment. The complexes [Ni2(PMTA)(Ph2-phen)4] (1) and [Ni2(PMTA)(Me2-phen)4] (2) were further characterized by variable temperature magnetic susceptibility measurements (4-300 K) and the observed data were treated in terms of two theoretical models, givinh the exchange integrals J=-2.85 cm(-1) for (1) and -1.96 cm(-1) for (2). The result indicates that there is very weakly antiferromagnetic spin-exchange intraction between two the Ni(II) ions within each molecule.

5

Synthesis and magnetism of binuclear iron (II) complexes bridged by terephthalato dianions

100%

Li Y. T. , Yan C. W. , Liao D. Z.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 5

832-838

EN

Four new terephthalato-bridges iron(II) binuclear complexes of the formula [Fe2(TPHA)L4](ClO4)2, where L stands for 4,4'-dimethyl-2,2'-bipyridine (Me2bpy); 2,9-dimethyl-1,10-phenanthroline (Me2phen); 5-bromo-1,10-phenanthroline (Br-phen); 5-chloro-1, 10-phenanthroline (Cl-phen), respectively, and TPHA represents the terephthalate dianion, have been synthesized and characterized. Based on the elemental analyses, molar conductance and magnetic moments of room-temperature measurements, and spectroscopic studies, extended TPHA-bridged structures consisting of two iron(II) ions, each in an octahedral environment are proposed for these complexes. The [Fe2(TPHA)(Me2bpy)4](ClO4)2 (1) and [Fe2(TPHA)(Me2phen)4](ClO4)2 (2) complexes were characterized by variable temperature magnetic susceptibility (4-300K) measurements and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H=-2JS-1xS-2, giving the exchange integrals J=-2.15 cm -1 for (1) and J=-3.28 cm-1 for (2). This result indicates the presence of a weak antiferromagnetic spin-exchange interaction between the metal ions within each molecule.

6

Synthesis and Magnetism of -Dioximato-Bridged Heterotrinuclear Oxovanadium(IV)–Palladium(II)–Oxovanadium(IV) Complexes

100%

Li Y. T. , Liu Y. , Yan C. W.

Polish Journal of Chemistry

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2001

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tom Vol. 75, nr 11

1703-1710

EN

Four novel oxovanadium(IV)–palladium(II)–oxovanadium(IV) heterotrinuclear complexes of the formula [(VO)2Pd(-FD)2L2]SO4, where (-FD)2 represents -furildioximato and L denotes: 5-methyl-1,10-phenanthroline (Me-phen), 2,9-dimethyl-1,10- phenanthroline (Me2-phen), 5-chloro-1,10-phenanthroline (Cl-phen) and 5-bromo- 1,10-phenanthroline (Br-phen), have been synthesized and characterized by elemental analyses, molar conductance and magnetic moments of room-temperature measurements, IR and electronic spectral studies. It is proposed that these complexes have extended dioximato-bridged structures and consist of two oxovanadium(IV) and a palladium( II) ions, in which the central palladium(II) ion has a square-planar environment and the end capped two oxovanadium(IV) ions have a square-pyramidal environment. The magnetic properties of complexes [(VO)2Pd(-FD)2(Me-phen)2]SO4 (1) and [(VO)2Pd(- FD)2(Me2-phen)2]SO4 (2) were investigated over the 4.2~300 K range and correspond to what is expected for an antiferromagnetic VO(IV)–VO(IV) pair with SVO(IV) = 1/2 and SPd(II) = 0 (Pd2+ is a diamagnetic in a square-planar environment) local spins. The exchange integral (J) was evaluated as J = 28 cm1 for (1) and J = 6.19 cm1 for (2) based on the spin Hamiltonian operator, H=- 2JS S1 x S2

7

Synthesis, Characterization and Magnetic Study of mi-Oxamido-Bridged Copper(II)–Lanthanide(III) Heterobinuclear Complexes

100%

Li Y. T. , Yan C. W. , Wang H. D.

Polish Journal of Chemistry

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2000

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tom Vol. 74, nr 12

1655-1663

EN

Ten new mi -oxamido-bridged copper(II)–lanthanide(III) heterobinuclear complexes described by the overall formula Cu(Br4obbz)Ln(phen)2NO3 (Ln = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er), where Br4obbz denotes the oxamido-N,N-bis(3,5-dibromobenzoato) and phen represents 1,10-phenanthroline, have been synthesized and characterized by the elemental analyses, magnetic moments (at room temperature), molar conductivity measurements and spectroscopic (IR, UV, ESR) studies. The temperature dependence of the magnetic susceptibility of Cu(Br4obbz)Gd(phen)2NO3 complex was measured over the range 4.2–300 K. The least-squares fit of the experimental susceptibilities based on the spin Hamiltonian operator,

8

Synthesis and magnetism of heterobinuclear Cu(II)-Fe(II) complexes bridges by N,N'-bis(3-aminopropyl)oxamidocopper(II)

100%

Li Y. T. , Yan C. W. , Zhu X. D. , Liao D. Z.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 3

485-491

EN

Four new my-oxamido heterobinuclear complexes have been synthesized and characterized, namely[Cu(oxpn)Fe(L)2]SO4, here oxpn denotes the N,N'-bis(3-aminopropyl)oxamido dianion and L represents 1,10-phenanthroline (phen); 5-nitro-1,10-phenanthroline (NO2-phen); 5-chloro-1,10-phenanthroline (Cl-phen) and 2,2'-bipyridine (bpy). Based on the elemental analyses, spectroscopic studies, magnetic moments (at room temperature) and molar conductivity measurements, extended oxamido-bridged structures consisting of a copper(II) and an iron(II) ions, which have a square planar environment and an octahedral environment, respectively, are proposed for these complexes. The [Cu(oxpn)Fe(bpy)2]SO4 (1) and [Cu(oxpn)Fe(phen)2]SO4 (2) complexes have been characterized by variale temperature magnetic susceptibility (4.2-300K) and the observed data were least-squares fitted to the susceptibility equation derived from the spin Hamiltonian including single-ion zero-field interaction for the iron (II) oion, H=-2J S(1)xS(2) - DS(z), giving the exchange integrals J=-21.8 cm(-1) for (1) and J=-23.2 cm(-1) for (2). These results are commensurate with antiferromagnetic interactions between adjacent metal ions within each molecule.

9

Synthesis, Crystal Structure and DNA Binding Studies of a New Binuclear Cobalt(III) Complex Bridged Both by mi-Peroxo and mi-Hydroxyl Groups

88%

Jiang M. , Li Y. T. , Wu Z. Y. , Peng W. B. , Li Q. L.

Polish Journal of Chemistry

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2009

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tom Vol. 83, nr 3

349-361

EN

A new binuclear cobalt(III) complex bridged both by mi-peroxo and mi-hydroxyl groups, and end-capped with 4,4 -dimethyl-2,2 -bipyridine (Me2bpy), namely, [Co2( -O2)( -OH)(Me2bpy)4](ClO4)3, has been synthesized and characterized by elemental analysis, IR, UV and single-Crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c and Z = 4, with a = 24.148(5) capital A, b = 10.628(2) capital A, c = 16.306(3) ?, and b = 90.74(3)°. The single crystal X-ray analysis reveals that the complex is composed of three per chlorate anions and a binuclear cobalt(III) cation, in which the cobalt(III) atoms are bridged both by hydroxyl and peroxo groups. Each cobalt(III) atom exhibits an octahedral geometry. A three-dimensional supramolecular arrangement in the crystal is generated by non-classical hydrogen bonds. The DNA-Binding properties of the complex were explored by using absorption and emission spectra and electrochemical methods. The result suggests that the binuclear cobalt(III) complex interacts with herring sperm DNA (HS-DNA) in the mode of intercalation with the intrinsic binding constant of 1.1×103 M-1.