Effect of p-tert-butylcalix[4]arene fitted with phosphinoyl pendant arms as synergistic agent in the solvent extraction of trivalent lanthanoids with 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione and structural study of solid complexes by IR, NMR and X-ray

Coordination chemistry of a para-tert-octylcalix[4]arene fitted with phosphinoyl pendant arms towards 4f-elements: Extraction, synergism, separation

“…The most shifted protons upon coordination are methyl group and o-Ph protons from one of the phenyl ring in HP ( Figure 6). There is no change in the symmetry of ligand S upon coordination and all resonances of S remain in the same form as for free S ligand, which indicates uniform interaction of all P=O with Eu 3+ ion, as already observed in our previous investigations (26,27,30). The 31 P { 1 H} NMR spectra of EuP 3 ·S complex at 298, 313 and 333 K consist of a single resonance, which supports the conclusion of uniform interaction of all P=O with Eu 3+ ion ( Figure 6).…”

“…It is well known that P=O groups show a high affinity for f-elements. Tetra-phosphinoylated para-tertbutylcalix [4]arene (25)(26)(27) and octa-phosphinoylated para-tert-octylcalix [8]arene (28) compounds have been demonstrated to be useful synergistic agents for the solvent extraction of lanthanoids in combination with chelating or neutral (4) ligands using molecular diluent (CHCl 3 ) and ionic liquid (29). It has been established that the physicochemical properties of lower rim phosphinoylated reagents mainly depend on the size, the number of functional groups and the compound conformation whereas this dependency is not so clear for upper rim phosphoruscontaining ligands.…”

Comparing extraction, synergism and separation of lanthanoids using acidic and neutral compounds in chloroform and one ionic liquid: is the latter always “better”?

“…As part of our systematic work on the synergistic solvent extraction of lanthanoids, [1][2][3][4][5][6][7][8] we performed comparative studies aiming at (i) improving the extraction ability of b-diketone compounds by increasing their acidity, (ii) studying the dependence of the extraction properties on the number of the ligating groups on a calixarene scaffold and nally, (iii) understanding the role of the solvent for extraction, separation and synergism by comparing a traditional molecular solvent, chloroform, and one ionic liquid, namely 1-methyl-3-butylimidazolium bis(triuoromethanesulfonyl)imide, there-aer denoted as [C 1 C 4 im][Tf 2 N]. It is our opinion that the wellassessed strategy based on the individual independent improvements of the extractants used in a synergistic system, which has proven to be quite efficient in molecular solvents, [1][2][3][4][5][6][7][8] may nd some limitations in ionic liquids (ILs). Ionic liquids are studied for an increasing number of applications in various aspects of chemistry and of course liquid-liquid extraction of rare earths and other metals.…”

“…Second, calixarenes are a versatile class of supramolecular compounds widely exploited as molecular platforms for the introduction of specic ligating arms in a reorganized pattern suitable for metal ions complexation. [1][2][3][4][5][6][7][8][24][25][26] Depending on the nature of the ligating groups, on the dimension of the macrocyclic scaffold and on the hydrophobicity, calixarenes have shown immense selectivity in the separation of alkaline and alkaline earth ions, 27 heavy metals 28 and f-elements. 1,29 The latter and the tunable shape of the molecules make them ideal candidates for building blocks and molecular scaffolds in the design of new and more sophisticated ligands.…”

Synergistic Solvent Extraction of Lanthanides(III) with Mixtures of 4-Benzoyl-3-Methyl-1-Phenyl-5-Pyrazolone and Phosphoryl-Containing Podands

“…Many studies have been carried out using phosphorus-containing calix [n] arenes as a synergistic agent at the Ln(III) extraction with various acidic chelating extractants of β-diketone type. [21][22][23][24][25][26] The introduction of P(O) functional groups in the calixarene architecture leads to a significant increase in the extraction efficiency. 26 The addition of phosphorus-containing calix [6]arene to the chelating extractant, 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone, improves the Ln(III) extraction and produces very large synergistic effects (more than five orders of magnitude).…”