The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mo...The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.展开更多
One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported ...One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported that the stacking interaction was observed between pyridine ring of bpy（bpy=2, 2′-bipyridyl） and purine ring of ATP<sup>4-</sup>(ATP<sup>4-</sup>=adenosine 5′-triphosphate) among the mixed-ligand Cu（bpy） （ATP）<sup>2-</sup> complexes. The study on this field has been extended to a large amount of ligands such as nucleotides, xanthosines,展开更多
So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability ...So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability of the complexes, but less to the interaction between those non-coordinating groups. Although the existence of hydrogen bonds between ligands and the formation of covalent and ionic bonds have been reported, it is only about ten展开更多
A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-r...A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.展开更多
The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is...The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is five. The molecular structure is linear one dimensional network. There is a stacking effect between pyridine ligands of neighbouring 1 D chains and the molecular structure is extended into two dimensional stacking network. Two salicylates in the complex have a position of crab pincers like, in which one salicylate is unidentate and another coordinates through the carboxylate group and phenyl group unidentately.展开更多
The stability constants of the ternary mixed ligand complexes Pt(Phen)(CA) +(Phen=1,10 Phenanathroline,CA=carboxylate Ligands) were determined by potentiometric pH titration in aqueous solution and in 30～90%(V/V) aqu...The stability constants of the ternary mixed ligand complexes Pt(Phen)(CA) +(Phen=1,10 Phenanathroline,CA=carboxylate Ligands) were determined by potentiometric pH titration in aqueous solution and in 30～90%(V/V) aqueous ethanal(I=0.1mol·L -1 ,KNO 3;25℃).The difference of stability among the different complexes was compared and discussed,and the percentages of the stacked isomers in the ternary mixed ligand complexes Pt(Phen)(PCA) +(PCA=2 phenylacetate and 3 phenylpropionate) was calculated.The experimental results indicate that the extent of the intramolecular aromatic ring stacking interaction in the ternary mixed ligand Pt(Phen)(PCA) + complexes depends on the polarity of the solution.The weaker the polarity of the solution,the more notable the intramolecular aromatic ring stacking interaction,the larger the percentage of the stacked isomers in the ternary complexes,and the more stable the ternary mixed ligand complexes.展开更多
基金Supported by the Foundation of Academ y L eader of Zhejiang Gongshang U niversity(No.19972 0 0 2 )
文摘The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.
基金Project supported by the National Natural Science Foundation of China
文摘One of the typical phenomena of intramolecular ligand-ligand interaction in complexes is the aromatic-ring stacking which depends on the stacking of those non-coordinating aromatic rings. Since 1974 H. Sigel reported that the stacking interaction was observed between pyridine ring of bpy（bpy=2, 2′-bipyridyl） and purine ring of ATP<sup>4-</sup>(ATP<sup>4-</sup>=adenosine 5′-triphosphate) among the mixed-ligand Cu（bpy） （ATP）<sup>2-</sup> complexes. The study on this field has been extended to a large amount of ligands such as nucleotides, xanthosines,
基金Project supported by the National Natural Science Foundation of China.
文摘So far, more attention was paid to the fact that the kind, position and properties of the substituted radicals of coordinating or non-coordinating groups in the complexes exert an important influence on the stability of the complexes, but less to the interaction between those non-coordinating groups. Although the existence of hydrogen bonds between ligands and the formation of covalent and ionic bonds have been reported, it is only about ten
文摘A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.
文摘The title complex, [Cu(Hsal)2(py)2], was synthesized by layered solution technique and structurally characterized by single crystal X ray. The copper atom has a square pyramidal geometry and the coordination number is five. The molecular structure is linear one dimensional network. There is a stacking effect between pyridine ligands of neighbouring 1 D chains and the molecular structure is extended into two dimensional stacking network. Two salicylates in the complex have a position of crab pincers like, in which one salicylate is unidentate and another coordinates through the carboxylate group and phenyl group unidentately.
文摘The stability constants of the ternary mixed ligand complexes Pt(Phen)(CA) +(Phen=1,10 Phenanathroline,CA=carboxylate Ligands) were determined by potentiometric pH titration in aqueous solution and in 30～90%(V/V) aqueous ethanal(I=0.1mol·L -1 ,KNO 3;25℃).The difference of stability among the different complexes was compared and discussed,and the percentages of the stacked isomers in the ternary mixed ligand complexes Pt(Phen)(PCA) +(PCA=2 phenylacetate and 3 phenylpropionate) was calculated.The experimental results indicate that the extent of the intramolecular aromatic ring stacking interaction in the ternary mixed ligand Pt(Phen)(PCA) + complexes depends on the polarity of the solution.The weaker the polarity of the solution,the more notable the intramolecular aromatic ring stacking interaction,the larger the percentage of the stacked isomers in the ternary complexes,and the more stable the ternary mixed ligand complexes.
