Tripodal organophosphorus ligands as synergistic agents in the solvent extraction of lanthanides(III). Structure of mixed complexes and effect of diluents. (15th March 2019)

• Record Type: Journal Article
• Authors: Turanov, Alexander N.; Matveeva, Anna G.; Kudryavtsev, Igor Yu.; Pasechnik, Margarita P.; Matveev, Sergey V.; Godovikova, Maria I.; Baulina, Tatyana V.; Karandashev, Vasilii K.; Brel, Valery K.
• Is Part Of: Polyhedron. Volume 161(2019)
• Page Start: 276
• Page End: 288
• Publication Date: 2019-03-15
• Subjects: Lanthanides(III) -- Synergistic extraction -- Tripodal organophosphorus ligands -- Solution structure -- Diluent effect; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2019.01.036
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: The efficiency of synergistic extraction of Ln(III) is determined by solution structure of the complexes. Solution structure of mixed complexes [LaPy3 L] is dependent on the structure of ligand L and solvent nature (toluene or CHCl3 ). Abstract: The solvent extraction of lanthanides (III) (except for Pm) from chloride medium (at μ = 0.1) into an organic phase containing 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone (HPy ) and neutral tripodal ligands on the triphenylphosphine oxide platform with anchored carbamoyl side arms (2-R2 NC(O)CH2 OC6 H4 )3 PO, where R = Bu (L1 ) and cyclo -Hex (L2 ) has been studied. A considerable synergistic effect (up to 10 7 ) has been observed in the presence of neutral ligandsL1 orL2 in the organic phase containingHPy . The stoichiometry of the Ln(III) extracted species has been determined by slope analysis and the equilibrium constants have been calculated. It has been found that the lanthanides(III) ions are extracted with mixtures ofHPy and neutral ligandsL1 orL2 in toluene as LnPy 3 L species. The [LaPy 3 (H2 O)2 ], and new [LaPy 3 (L1 )] and [LaPy 3 (L2 )] complexes have been synthesized and characterized via elemental analysis and IR spectroscopy. Solution structure of the above complexes has been examined by IR and multinuclear ( 1 H, 13 C, and 31 P) NMR spectroscopy in toluene- d 8 and CDCl3 . The effect of diluents on synergistic extraction and the solution structure of mixed complexes are discussed.