Extraction of lanthanides(III) by phosphorylated naphthyridine ligands from carbonate solutions

The extraction capacities and selectivities of 1,8-naphthyridine-based neutral organophosphorus reagents in extracting trivalent lanthanides (Ln, Nd, Ho, Yb) from carbonate solutions were studied. The length and nature of the linker between the naphthyridine and phosphoryl moieties were found to have considerable influence on the efficiency and selectivity of lanthanide extraction.     

Complexation of uranium(VI) and europium(III) with new polydentate pincer ligands in aqueous systems

Coordination of uranyl ion with new polydentate ligands derived from amino acids and extraction of uranium(VI) and europium(III) from aqueous salt solution into poly(ethylene glycol) phase with the use of new polydentate pincer ligands has been studied.     

Extraction of f-elements from nitric acid solutions with phosphoryl ketones

The extraction ability and selectivity of a series of phosphoryl ketones Ph₂P(O)CH₂C(O)Me, and Ph₂P(O)CRR’CH₂C(O)Me (R = H, Me; R’ = H, Me, n-C₅H₁₁, Ph, 2-thienyl, 2-furyl) towards trivalent lanthanides (La^III, Nd^III, Ho^III, Yb^III) and actinides (U^VI, Th^IV) were studied. The efficiency and selectivity of the new ligands in the extraction of f-elements from nitric acid solutions into chloroform were compared to those of model phosphine oxide Ph₂P(O)Bu and known extractants: tributyl phosphate (BuO)₃P(O), trioctylphosphine oxide (C₈H₁₇)₃P(O), and carbamoylmethyl phosphine oxide Ph₂P(O)CH₂C(O)NBu₂.     

α- and β-diphenylphosphorylated secondary alkanols: I. general method of synthesis and extraction properties towards <Emphasis Type="Italic">f</Emphasis>-elements

A simple and effective general method of synthesis of α- and β-diphenylphosphorylated secondary alkanols by the reduction of the corresponding phosphorylalkanones with NaBH4 was developed. The extraction properties of the resulting phosphorylalkanols Ph₂P(O)(CR₂)_nCH₂CH(OH)Me (n = 0, 1; R = H, Me) were studied in the recovery of f-elements (La^III, Nd^III, Ho^III, Yb^III, U^VI, Th^IV) from nitric acid solutions into chloroform and compared with those of both related phosphorylketones and known extractants (n-BuO)₃PO, (n-C₈H₁₇)₃PO, and Ph₂P(O)CH₂C(O)N(n-Bu)₂.     

Acetyl-containing phosphine oxides as extractants for actinides and lanthanides

Extraction capability and selectivity of acetyl-containing phosphine oxides R₂P(O)CMe₂CH₂C(O)Me (R = Pr, Bu, n-C₅H₁₁, n-C₆H₁₃, n-C₈H₁₇, Ph) toward actinides (U^VI, Th^IV) and trivalent lanthanides (La^III, Nd^III, Ho^III, Yb^III) were studied. The new ligands were shown to be more efficient and selective in the extraction of uranium, thorium, and heavy lanthanides from nitric acid solutions into chloroform as compared to the known extractants such as carbamoylphosphine oxide Ph₂P(O)CH₂C(O)NBu₂, trioctylphosphine oxide (n-C₈H₁₇)₃P(O), and tributyl phosphate (n-BuO)₃P(O).     

N-(1,5-dimethyl-3-oxo-2-phenyl-1,2-dihydropyrazol-4-yl)-P,P-diphenylamidophosphinate and its complexes with neodymium(III), erbium(III), thorium(IV), and uranyl nitrates: Synthesis and crystal and molecular structure

A new phosphoryl-containing ligand based on 4-aminoantipyrine-N-(1,5-dimethyl-3-oxo-2-phenyl-1,2-dihydropyrazol-4-yl)-P,P-diphenylamidophosphinate (L) was synthesized. In crystals, the L molecules were found to be combined in centrosymmetric dimers through N-H…O=C hydrogen bonds. The complexes of L with neodymium(III), erbium(III), thorium(IV), and uranyl nitrates were obtained, and their structures were determined. The bands of the C=O and P=O groups in the IR spectra of these complexes are shifted toward low frequencies (by 50–65 and 40–70 cm⁻¹, respectively), which is indicative of a bidentate coordination of the organophosphorus ligand. According to the X-ray crystallography data, uranyl is bidentately coordinated by both the L molecule (through the C=O and P=O groups) and two nitrate anions.     

Complexes of (2-methyl-4-oxopent-2-yl)diphenylphosphine oxide with uranyl and neodymium nitrates: synthesis and structures in the solid state and in solution

The reactions of (2-methyl-4-oxopent-2-yl)diphenylphosphine oxide (L) with uranyl and neodymium nitrates afforded complexes with compositions M: L = 1: 2 and 1: 3. These complexes were characterized by X-ray diffraction, IR spectroscopy, and elemental analysis. In the solid complexes, phosphine oxide L has a variable denticity. Studies by ¹H and ³¹P NMR and IR spectroscopy showed that in chloroform, the mononuclear complexes [UO₂(O-L)₂-(O,O-NO₃)₂], [Nd(O-L)₂(O,O-NO₃)₃] and [Nd(O-L)₃(O,O-NO₃)₃] are neutral, and the ligand molecules are coordinated to the metal cation through the phosphoryl oxygen atom.