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
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
The intramolecular aromatic-ring stacking interaction of mixed- ligand complex Pd(A)(UTP)^(2-)in the system pd^(2+)-A-UTP^(4-)has been determined by ~1HNMR,where A=1,10-phenanthroline(phen),2,2'-bipyridyl(bpy)and ...The intramolecular aromatic-ring stacking interaction of mixed- ligand complex Pd(A)(UTP)^(2-)in the system pd^(2+)-A-UTP^(4-)has been determined by ~1HNMR,where A=1,10-phenanthroline(phen),2,2'-bipyridyl(bpy)and DL- tryptophan(trp^-);UTP^(4-)=uridine 5-triphosphate.The result indicates that it is the partial stacking between the uracil ring of UTP^(4-)and the heterocyclic ring of A that makes H(5),H(6)and H(1')in the UTP^(4-)shift upfield signifi- cantly.Accordingly,the order of aromatic-ring interaction in the mixed- ligand complex has been obtained as follows:Pd(phen)(UTP)^(2-)(?)Pd(bpy)(UTP)^(2-) Pd(trp)(UTP)^(3-).展开更多
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.
文摘The intramolecular aromatic-ring stacking interaction of mixed- ligand complex Pd(A)(UTP)^(2-)in the system pd^(2+)-A-UTP^(4-)has been determined by ~1HNMR,where A=1,10-phenanthroline(phen),2,2'-bipyridyl(bpy)and DL- tryptophan(trp^-);UTP^(4-)=uridine 5-triphosphate.The result indicates that it is the partial stacking between the uracil ring of UTP^(4-)and the heterocyclic ring of A that makes H(5),H(6)and H(1')in the UTP^(4-)shift upfield signifi- cantly.Accordingly,the order of aromatic-ring interaction in the mixed- ligand complex has been obtained as follows:Pd(phen)(UTP)^(2-)(?)Pd(bpy)(UTP)^(2-) Pd(trp)(UTP)^(3-).
