Polyether carboxylic acids incorporating a benzodioxinic subunit: synthesis and complexing ability of sodium and potassium

1992 ◽  
Vol 70 (3) ◽  
pp. 828-835 ◽  
Author(s):  
Pascal Bosseray ◽  
Gérard Coudert ◽  
Gérald Guillaumet ◽  
Georges Jeminet ◽  
Madeleine Tissier ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Formation Constants ◽  
Side Chain ◽  
Complexing Ability ◽  
Potentiometric Measurements ◽  
Sodium And Potassium

We report here the synthesis of new polyoxygenated macrocyclic derivatives with a benzodioxinic subunit and a carboxylic side chain (2, 3), along with some of their corresponding acyclic polyethers (1). Formation constants of sodium and potassium complexes with both the acid and anion forms of these compounds were obtained from potentiometric measurements. The enhancement of both complexing ability and selectivity afforded by the presence of a carboxylic side chain is discussed. Keywords: polyether carboxylic acids, macrocycles, benzo-1,4-dioxin, sodium and potassium complexes, solvent methanol.

Complexation du cuivre(II) par les phénylsérines thréo et érythro: étude thermodynamique

1985 ◽  
Vol 63 (1) ◽  
pp. 46-51 ◽  
Author(s):  
Patrick Sharrock
Keyword(s):  
Aqueous Solution ◽  
Thermodynamic Parameters ◽  
Formation Constants ◽  
Side Chain ◽  
Potentiometric Measurements

Conductimetric and potentiometric measurements in aqueous solution as a function of temperature show that cupric ions promote the deprotonation of the hydroxy side chain of threo and erythro β-phenylserines. The threo ligand yields at 298 K the formation constants: Cu(L), K1 = 7.99; Cu(L)2, K2 = 6.71; Cu(L2H−1), K3 = −9.51; Cu(L2H−2), K4 = −10.83. The erythro isomer yields the corresponding constants: K1 = 7.70, K2 = 6.70, K3 = −9.82, and K4 = −11.20. Thermodynamic parameters for the first two complexation steps are −ΔH = 21.3 and 44.7 kJ mol−1; ΔS = 82 and 132 J K−1 mol−1, respectively, for the threo form and −ΔH = 20.7 and 44.1, ΔS = 79 and 129 for the erythro form. Deprotonation of the complexes corresponds to an additional enthalpy of −21 kJ mol−1. These results and the structures of the complexes are discussed.

ChemInform Abstract: Polyether Carboxylic Acids Incorporating a Benzodioxinic Subunit: Synthesis and Complexing Ability of Sodium and Potassium

ChemInform ◽  
2010 ◽  
Vol 23 (47) ◽  
pp. no-no
Author(s):  
P. BOSSERAY ◽  
G. COUDERT ◽  
G. GUILLAUMET ◽  
G. JEMINET ◽  
M. TISSIER ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Complexing Ability ◽  
Sodium And Potassium

scholarly journals Interaction of Ampicillin and Amoxicillin with Mn2+: A Speciation Study in Aqueous Solution

Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3110
Author(s):  
Claudia Foti ◽  
Ottavia Giuffrè
Keyword(s):  
Aqueous Solution ◽  
Stability Constants ◽  
Metal Ion ◽  
Formation Constants ◽  
Enthalpy Change ◽  
Ligand Concentration ◽  
Empirical Parameter ◽  
Speciation Study ◽  
Potentiometric Measurements ◽  
The Stability

A potentiometric and UV spectrophotometric investigation on Mn2+-ampicillin and Mn2+-amoxicillin systems in NaCl aqueous solution is reported. The potentiometric measurements were carried out under different conditions of temperature (15 ≤ t/°C ≤ 37). The obtained speciation pattern includes two species for both the investigated systems. More in detail, for system containing ampicillin MLH and ML species, for that containing amoxicillin, MLH2 and MLH ones. The spectrophotometric findings have fully confirmed the results obtained by potentiometry for both the systems, in terms of speciation models as well as the stability constants of the formed species. Enthalpy change values were calculated via the dependence of formation constants of the species on temperature. The sequestering ability of ampicillin and amoxicillin towards Mn2+ was also evaluated under different conditions of pH and temperature via pL0.5 empirical parameter (i.e., cologarithm of the ligand concentration required to sequester 50% of the metal ion present in traces).

Comparison of calcium complexation of some carboxylic acids derived from D­glucose and D-fructose

1995 ◽  
Vol 73 (8) ◽  
pp. 1338-1347 ◽  
Author(s):  
Hélène Bazin ◽  
Gérard Descotes ◽  
Alain Bouchu ◽  
Michelle Petit-Ramel
Keyword(s):  
Molecular Structure ◽  
Complex Formation ◽  
Carboxylic Acids ◽  
Formation Constants ◽  
Ion Selective Electrode ◽  
Selective Electrode ◽  
Complex Formation Constants ◽  
Calcium Complexation ◽  
C Nmr

The aim of this work was to compare calcium sequestering behaviour of 11 carboxylic acids derived from carbohydrates, and to study the influence of molecular structure on the calcium complexation. For this purpose, various carboxylic acids derived from methyl D-glucopyranoside, methyl D-fructopyranoside, and methyl D-fructofuranoside were synthesized and studied using an ion selective electrode to determine calcium complex formation constants. Complexation sites of carbohydrate skeletons were determined using 13C NMR. Keywords: Ca(II) complexation, carboxylic acids, fructofuranosides, fructopyranosides, glucopyranosides.

The limiting conductivity of the borate ion and its ion-pair formation constants with sodium and potassium under hydrothermal conditions

2016 ◽  
Vol 18 (34) ◽  
pp. 24081-24094 ◽  
Author(s):  
H. Arcis ◽  
J. P. Ferguson ◽  
G. H. Zimmerman ◽  
P. R. Tremaine
Keyword(s):  
High Precision ◽  
Ac Conductivity ◽  
Formation Constants ◽  
Ion Pair ◽  
Pair Formation ◽  
Association Constants ◽  
Potassium Ions ◽  
Hydrothermal Conditions ◽  
Sodium And Potassium ◽  
Limiting Conductivity

The limiting conductivity of borate and its association constants with sodium and potassium ions have been determined from T = 298 K to T = 623 K at p = 20 MPa, using a high-precision flow AC conductivity instrument.

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