2,6-Bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3-yl)pyridine as a Ligand for Efficient Actinide(III)/Lanthanide(III) Separation

Abstract

The N-donor complexing ligand 2,6-bis(5-(2,2-dimethylpropyl)-1H-pyrazol-3-yl)pyridine (C5-BPP) was synthesized and screened as an extracting agent selective for trivalent actinide cations over lanthanides. C5-BPP extracts Am(III) from up to 1 mol/L HNO(3) with a separation factor over Eu(III) of approximately 100. Due to its good performance as an extracting agent, the complexation of trivalent actinides and lanthanides with C5-BPP was studied. The solid-state compounds [Ln(C5-BPP)(NO(3))(3)(DMF)] (Ln = Sm(III), Eu(III)) were synthesized, fully characterized, and compared to the solution structure of the Am(III) 1:1 complex [Am(C5-BPP)(NO(3))(3)]. The high stability constant of log β(3) = 14.8 ± 0.4 determined for the Cm(III) 1:3 complex is in line with C5-BPP's high distribution ratios for Am(III) observed in extraction experiments.

High-Performance Alkyl Diamide Amine and Water-soluble Diamide Ligand for Separating of Am(III) from Cm(III)

“…The separation of these two closely related MAs is even more challenging than that of MA(III) and Ln(III). [3][4][5] Although various ligands and separation methods have been studied for the Am(III)/Cm(III) separation, [6][7][8][9][10][11] an effective approach for practical use has not yet been developed.…”

Supramolecular assembly and transfer hydrogenation catalysis with ruthenium(II) complexes of 2,6-di(1H-pyrazol-3-yl)pyridine derivatives

“…Importantly, the displacement of the chloride ligand by solvent in crystals of 3·H were treated with 2 equiv AgPF 6 to exchange the chloride ions for more weakly associating PF 6 . These reactions proved sluggish; significant chloride remained in the materials by microanalysis after reactions at room temperature, while reactions under reflux led to mixtures of products.…”

“…Complexes of ligands derived from 2,6-di(pyrazol-3-yl)pyridine Scheme 1) are finding increasing use [1], in fields as diverse as spin-crossover compounds [2,3], dyesensitized solar cells [4], emissive materials [5], metal ion separation [6] and catalysis [7][8][9][10][11][12][13][14][15][16][17].…”

Highly Practical and Simple Ligand for Separation of Am(III) and Eu(III) from Highly Acidic Media

“…Furthermore, other severe problems associated with soft donor ligands are slow extraction, poor solubility in nonpolar solvents, difficult synthesis, and high cost. [6][7][8][9] Therefore, no effective extractant has been developed for practical use to date.…”