Weak complexes of sulphur and selenium. Part III. Effect of solvent on the stability of 1 : 1 complexes of sulphur dioxide, sulphinyl dichloride, and sulphonyl dichloride with halogen ions

Ethylenediphosphinetetraacetic acid is bonded to metal ions in aqueous solutions in four ways, depending on the type of metal ion: 1) through an ionic bond of the carboxylic groups to form weak complexes with a metal:ligand ratio of 1 : 1 (Ca(II), Mn(II), Zn(II), Pb(II), La(III)); 2) through type 1) bond with contributions from weak interaction with the phosphorus (Cd(II)); 3) through coordination of the ligand as a monodentate P-donor with the free carboxyl groups with formation of 2 : 1 and 1 : 1 complexes (Cu(I), Ag(I)); 4) through formation of square planar or, for Hg(II), tetrahedral complexes with a ratio of 1 : 2 with the ligand as a bidentate PP-donor with the free carboxyl groups (Fe(II), Co(II), Ni(II), Pd(II), Pt(II)). On acidification of the complex solution, the first two protons are bonded to the carboxyl groups. The behaviour during further protonation depends on the type of complex: in complexes of types 1) and 2) phosphorus is protonated and the complex dissociates; in complexes of types 3) and 4) the free carboxyl groups are protonated and the phosphorus-metal bond remains intact. The results are based on correlation of the stability constants, UV-visible, infrared, 1H and 31P NMR spectra and magnetic susceptibilities of the complexes in aqueous solution.

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Effect of solvent nature on the stability of highly dispersed and nanosized cadmium telluride

Russian Journal of Inorganic Chemistry ◽

10.1134/s0036023613100124 ◽

2013 ◽

Vol 58 (10) ◽

pp. 1166-1171 ◽

Cited By ~ 3

Author(s):

O. A. Kapush ◽

L. I. Trishchuk ◽

V. N. Tomashik ◽

Z. F. Tomashik ◽

S. D. Boruk

Keyword(s):

Cadmium Telluride ◽

Solvent Nature ◽

Effect Of Solvent ◽

Highly Dispersed ◽

The Stability

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Weak complexes of sulphur and selenium. Part 5. Halide-ion replacement in 1:1 complexes of sulphur dioxide, thionyl chloride, and sulphonyl choride with halide ions in acetonitrile and dimethyl sulphoxide

Journal of the Chemical Society Dalton Transactions ◽

10.1039/dt9780000915 ◽

1978 ◽

pp. 915 ◽

Cited By ~ 3

Author(s):

M. A. Khan ◽

Saad Wasif ◽

S. B. Salama

Keyword(s):

Thionyl Chloride ◽

Sulphur Dioxide ◽

Dimethyl Sulphoxide ◽

Halide Ions ◽

Weak Complexes

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The determination of the stoichiometry and stability constant of weak complexes in solution: a restatement of the "straight-line" method

Canadian Journal of Chemistry ◽

10.1139/v83-195 ◽

1983 ◽

Vol 61 (6) ◽

pp. 1100-1102 ◽

Cited By ~ 9

Author(s):

Aurelio Beltrán-Porter ◽

José A. Ramírez

Keyword(s):

Stability Constant ◽

Stoichiometric Ratio ◽

Complex Species ◽

Line Method ◽

Straight Line ◽

Weak Complexes ◽

The Stability ◽

Degree Of Condensation ◽

Straight Line Method

Usually, to establish the degree of condensation of a complex species in solution, primarily when it is a weak complex, is more cumbersome than to determine the stoichiometric ratio itself. The present work describes a modification of the Asmus method in order to render it suitable for the determination of the actual stoichiometric coefficients and the stability constant of weak complexes whatever the degree of condensation may be.

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The interaction of [Pd(N,N-dimethylaminopropylamine)(H2O)]2+ with dicarboxylic acids and inosine: Thermodynamic model for carboplatin drug

Open Chemistry ◽

10.2478/s11532-012-0053-y ◽

2012 ◽

Vol 10 (4) ◽

pp. 1253-1261 ◽

Cited By ~ 1

Author(s):

Mohamed Shehate ◽

Mohamed Shoukry ◽

Mona Ragab

Keyword(s):

Dielectric Constant ◽

Stability Constant ◽

Equilibrium Constants ◽

Chloride Ion ◽

Dicarboxylic Acids ◽

Ion Concentration ◽

Antitumour Agents ◽

Effect Of Solvent ◽

Dna Constituents ◽

The Stability

AbstractThe Pd(DMPA)Cl2 complex, where DMPA = N,N-dimethylaminoproylamine, was synthesized and characterized. The stoichiometry and stability constants of the complexes formed between various dicarboxylic acids and [Pd(DMPA)(H2O)2]2+ were investigated. The effect of solvent dielectric constant, chloride ion concentration of the medium and temperature on the stability constant of the cyclobutanedicaroxylic acid (CBDCA) complex was investigated. The equilibrium constants for the displacement of coordinated CBDCA by inosine, taken as an example of DNA constituents, were calculated. The results are expected to contribute to the chemistry of antitumour agents.

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