Protonation and lanthanide(III) complexation equilibria of a new tripodal polyaza-polycatechol-amine

The sulfonated tripodal polyaza-polycatechol-amine ligand tris(2,3-hydroxy-5-sulfobenzylamine)ethyl)amine (STRENCAT) was synthesized and its protonation constants determined by potentiometry at 25 degrees C and in 0.1 mol dm(-3) NaClO(4). In the adopted experimental conditions (2.5 10, even in excess of ligand, in all the metal-ligand systems

Interaction of MO2++ ( M = U and Pu ) Ions with 5-Sulphosalicylic Acid in Aqueous Solution.

In aq. solns. with ionic strength of 1M (Na+, H+, ClO4-) at 20°, the stability consts. were log β = 11.30, 2.32, 10.30, and 9.24 for H+ + L3- ↔ HL2- (H3L = 5-sulfosalicylic acid), H+ + HL2- ↔ H2L-, UO22+ + L3- ↔ UO2L-, and PuO22+ + L3- ↔ PuO2L-, resp

Actinide Complexes in Aqueous Solution.

Stability consts. and thermodn. of coordination of actinides in aq. soln. are reviewed with 25 refs

Thermodynamic Properties of Actinide Complexes. Part VII. Uranyl(VI) - Succinate System.

In order to assess the effect of the no. of methylenic groups in the ligand chain on the stability consts. of complexes and on their heats, free energies, and entropies of formation, the uranyl (VI)-succinate system was studied at 25 \ub0C by calorimetric and potentiometric methods

Complexation of Eu(III) with alkyl-substituted malonamides in acetonitrile.

The complexation of Eu(III) with a series of alkyl-substituted malonamide ligands was studied in organic solvents using calorimetry, FT-IR and luminescence spectroscopy. The formation constants were determined in acetonitrile containing small amounts of dimethyl sulfoxide. The effects of substitution on the nitrogen atoms as well as on the central carbon atom were evaluated. For the substitution on the nitrogen atoms, the formation constants decrease in the order: N,N,N',N'-tetramethylmalonamide (TMMA) > N,N'-dibutyl-N,N'-dimethylmalonamide (DMDBMA) > N,N,N',N'-tetrahexylmalonamide (THMA) > N,N,N',N'-tetraisopropylmalonamide (TiPMA). For substitution on the central carbon atom, the formation constants decrease in the order: N,N,N',N'-tetrahexyl-2-methylmalonamide (MeTHMA) > N,N,N',N'-tetrahexylmalonamide (THMA) > N,N,N',N'-tetrahexyl-2,2-dimethylmalonamide (DMeTHMA). These orders are discussed in terms of the steric effect and the ligand basicity