Relative complexing tendencies of O—O, O—N, and O—S donor (secondary) ligands in some lanthanide–EDTA mixed-ligand complexes

1986 ◽  
Vol 64 (5) ◽  
pp. 865-870 ◽  
Author(s):  
Sudhir N. Limaye ◽  
Mahesh C. Saxena
Keyword(s):  
Ionic Strength ◽  
Association Constants ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Binary Complex ◽  
Electrostatic Repulsion ◽  
Aromatic Ligand ◽  
Titration Technique ◽  
Metal Ligand ◽  
Secondary Ligand

Metal–ligand association constants of 1:1 binary (ML) and 1:1:1 ternary (MAL) complexes of the type [Formula: see text] (where M = La3+, Ce3+, Pr3+, Nd3+, or Sm3+; A = primary ligand = EDTA; L = secondary ligand = O—O, O—N, O—S donor aliphatic or aromatic ligand) have been determined potentiometrically by the Irving–Rossotti titration technique at ionic strength 0.2 (mol dm−3 NaClO4) and 25 °C. Differences between log KML and log KMAL are negative; this may be chiefly due to electrostatic repulsion between the primary binary complex and the incoming secondary ligand during the formation of the mixed-ligand complexes. The relative complexing tendencies of various secondary ligands have been found to follow the sequence O—O donor (aromatic) > O—N donor > O—O donor (aliphatic) ≥ O—S donor.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) ions with N-(2-hydroxybenzylidene)-2,3-dimethylaniline as Primary Ligand and N-(2-hydroxy-1-naphthylidene)-4-nitroaniline as Secondary Ligand

2011 ◽  
Vol 8 (2) ◽  
pp. 859-862 ◽  
Author(s):  
A. K. Mapari ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Transition Metal ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
The Stability ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M=Co(II), Ni(II), Cu(II) and Zn(II); X=N-(2-hydroxybenzylidene)-2,3-dimethylaniline and Y =N-(2-hydroxy-1-naphthylidene)-4-nitroaniline] have been examined pH-metrically at 27±0.5 °C and at constant ionic strength, μ=0.1 M (KCl) in 75:25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) Ions with Salicylidene-4-methoxyaniline as Primary Ligand and 5-Bromosalicylidene-4-nitroaniline as Secondary Ligand

2011 ◽  
Vol 8 (4) ◽  
pp. 1765-1769 ◽  
Author(s):  
N. G. Nadkarni ◽  
K. V. Mangaonkar
Keyword(s):  
Ionic Strength ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
Binary Complexes ◽  
The Stability ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M = Mn(II), Ni(II), Cu(II) and Zn(II); X = salicylidene-4-methoxyaniline and Y=5-bromosalicylidene-4-nitroaniline] have been examined pH-metrically at 27±0.5 °C and at constant ionic strength, μ= 0.1 M (KCl) in 75 : 25(v/v) 1,4-dioxne-water medium. The stability constants for binary (M-Y) and ternary (M-X-Y) systems were calculated. The relative stability (Δ log KT) values of the ternary complexes with corresponding binary complexes for all the metal(II) ions in the present study found to be negative indicating that ternary 1:1:1 (M-X-Y) complexes are less stable than binary 1:1 (M-Y) complexes. In the ternary system studied, the order of stability constants of mixed ligand complexes with respect to the metal ions was found to be Cu(II) > NI(II) > Mn(II) > Zn(II); which is same as in the corresponding binary (M-Y) systems.

scholarly journals Stability Constants of Mixed Ligand Complexes of Transition Metal(II) Ions withN-(2-Hydroxy-1-naphthylidene)-2,6-diisopropylaniline as Primary Ligand and N-(2-Hydroxybenzylidene)-2,3-dimethylaniline as Secondary Ligand

2011 ◽  
Vol 8 (1) ◽  
pp. 123-126
Author(s):  
A. K. Mapari ◽  
K. V. Mangaonkar
Keyword(s):  
Transition Metal ◽  
Stability Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Water Medium ◽  
Binary And Ternary Complexes ◽  
Secondary Ligand

Binary and ternary complexes of the type M-Y and M-X-Y [M = Co(II), Ni(II), Cu(II) and Zn(II); X = N-(2-hydroxy-1-naphthylidene)-2,6-diisopropylaniline and Y =N-(2-hydroxybenzylidene)-2,3-dimethylaniline] have been examined pH-metrically at 27±0.5°C and µ = 0.1 M in 75: 25% (v/v) 1,4-dioxne-water medium. The logarithms of the values of stability constants for binary (M-Y) and for ternary (M-X-Y) systems were calculated.

Differential pulse polarographic studies on simple and mixed ligand complexes of Cd(II) with diaminopropane and adipate ligands

1990 ◽  
Vol 55 (10) ◽  
pp. 2381-2389
Author(s):  
Hamada M. Killa ◽  
El-Sayed M. Mabrouk ◽  
Abdel Fattah A. Abdel Fattah
Keyword(s):  
Differential Pulse ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Mixed Complexes ◽  
Diffusion Controlled ◽  
And Diffusion ◽  
Secondary Ligand

The composition, stability and equilibria of ternary complexes of Cd(II) with adipate (Adp) as primary ligand and 1,3-diaminopropane (DAMP) as secondary ligand have been studied using differential pulse (d.p.) polarography. The results reveal the presence of three ternary complexes with stoichiometries 1:1:1, 1:1:2, and 1:2:1. Also, the composition and stability of binary species have been determined. The reduction of simple and mixed ligand complexes is reversible and diffusion controlled. The formation constants of mixed complexes were calculated and compared with the observed values.

Studies on the Mixed Ligand Complexes Involving Ligands of Biological Importance (Ni(II)/Zn(II)/Cd(II)-1,10-phenanthroline-2,2′ -bipyridyl-phenylalanine)

1977 ◽  
Vol 32 (4) ◽  
pp. 426-429 ◽  
Author(s):  
G. S. Malik ◽  
S. P. Singh ◽  
J. P. Tandon
Keyword(s):  
Ionic Strength ◽  
Metal Ion ◽  
Formation Constants ◽  
Ternary Complexes ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Biological Importance

pH-metric studies on the interaction of Ni(II), Zn(II) or Cd(II) with 1,10-phenanthroline (Phen) or 2,2′-bipyridyl (Bipy) in the presence of phenylalanine (Phe) indicate the formation of 1:1:1 mixed ligand chelates and their monohydroxo derivatives. The addition of Phe takes place after the combination of Phen or Bipy with the metal ion is complete. The formation constants of the resulting complexes have been determined at 30 ± 1 °C and ionic strength (µ) = 0.1 KNO3 and the ternary complexes involving Phen are found to be more stable than the corresponding complexes involving Bipy as primary ligand.

Potentiometric Investigation of Mixed-Ligand Complexes of Co(II), Ni(II) and Zn(II) Ions with Thiosalicylic Acid and Ethylenediamine

1992 ◽  
Vol 57 (2) ◽  
pp. 263-267 ◽  
Author(s):  
Joanna Masłowska ◽  
Józef Szmich
Keyword(s):  
Ionic Strength ◽  
Thermodynamic Functions ◽  
Aqueous Ethanol ◽  
Mixed Ligand ◽  
Potentiometric Method ◽  
Mixed Ligand Complexes ◽  
Thiosalicylic Acid

Formation of mixed-ligand complexes of Co(II), Ni(II) and Zn(II) ions with thiosalicylic acid (H2SR) and ethylenediamine (en) in aqueous ethanol (50 vol.%) was investigated by the potentiometric method at 298, 313 and 328 K at the ionic strength of 0.1 (NaClO4). The thermodynamic functions ∆G0, ∆H0 and ∆S0 have been evaluated at these temperatures.

scholarly journals Solution and Solid State Study of Nickel(II) Ternary Complexes Containing 5-Aminolevulinic Acid Drug and Amino Acids

2020 ◽  
Vol 32 (7) ◽  
pp. 1563-1568
Author(s):  
Salhah D. Al-Qahtani
Keyword(s):  
Amino Acids ◽  
Aminolevulinic Acid ◽  
Molar Conductance ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Binary Complex ◽  
State Study ◽  
Square Planar ◽  
The Stability

Solution equilibria of the systems Ni(II)-5-aminolevulinic acid as ligand (A) and the amino acids [alanine (Ala), valine (Val), methylamine (Met), imidazole (Imi), Histidine (His), serine (Ser), cysteine (Cys) and penicillamine (Pen)] as ligands (L) have been studied pH-metrically. The stability constants of mixed ligand complexes were calculated with I = 0.10 mol L-1 KNO3 using HYPERQUAD program at 25 ± 0.1 ºC. The log10 X values showed a higher stabilities for the mixed ligand complexes compared to the binary analogues. The synthesis and characterization of the new amino acid mononuclear Ni(II) binary complex [NiA] (1) and ternary complex [NiAL] (2) were achieved via molar conductance, elemental analysis UV-vis, IR, 1H NMR, thermal analysis and magnetic moment. The thermogravimetric analysis of complexes were investigated by TG-DTA suggests that the complexes possess high thermal stability formation and their respective nickel oxide for 1 and nickel sulfide for 2 as final chemical entities, which are thermally stable. The nickel(II) chelates were found to be non-electrolytes, diamagnetic moments and the geometry around Ni(II) ion in complexes 1 and 2 is square planar

scholarly journals Formation Constants of Mixed Ligand Complexes of Anti-Inflammatory Drug Piroxicam and Some Bioligands with Copper(II)

2019 ◽  
Vol 31 (12) ◽  
pp. 2937-2940
Author(s):  
Amal M. Al-Mohaimeed
Keyword(s):  
Formation Constants ◽  
Mixed Ligand ◽  
Mixed Ligand Complexes ◽  
Inflammatory Drug ◽  
Relative Stabilization ◽  
Anti Inflammatory ◽  
Ph Range ◽  
Secondary Ligand

The formation constants of various complexes of copper(II) with anti-inflammatory drug piroxicam (P) as primary ligand and some bioligands such as L-serine, L-tyrosine, L-threonine as secondary ligand have been determined pH metrically at 25 ºC and I = 0.1 M NaNO3. The results suggest that the formation of Cu(P)L and Cu(P)(LH-1) species in the pH range of 5-12. The values of Δ log10 K, percentage of relative stabilization and log X were evaluated and discussed.

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