Remarkable Effect of Stereoisomerism on the Am(III)/Ln(III) Solvent Extraction. New Ligands for Highly Efficient Separation of Americium.

Two novel 1,10-phenanthroline-2,9-diamide ligands were constructed on the basis of 2-phenylpyrrolidine and obtained as pure diastereomers. These ligands demonstrated advanced properties in liquid-liquid extraction tests. They revealed high efficiency of americium(III) extraction alongside with the record values of selectivity in the separation of americium from light lanthanides from strongly acidic media.

First 4,7-oxygenated 1,10-phenanthroline-2,9-diamides: synthesis, tautomerism and complexation with REE nitrates.

A new family of phenanthroline ligands was prepared. Hydrolysis of 4,7-dihalogenated 1,10-phenanthroline-2,9-diamides in acidic media leads to the formation of the corresponding 4,7-oxygenated derivatives. These ligands can exist in different tautomeric forms.

1,2-Bis(triazolyl)tetraphenyldigermanes: Synthesis, Structure and Properties.

Using the [3+2] cycloaddition reaction of [HC≡C-GePh -] (1) and a number of RCH N , this work described the synthesis of a series of novel heterocyclic digermanes, bitriazoles [1,4-C HN (CH R)GePh -] , 2-12 (R=Ph, p-Tol, p-C H NMe , p-C H OMe, p-C H Br, m-C H NO , 2-Naphth, CH -p-OC H CHO, CH -p-OC H COOMe, CH P(O)(OEt) , COOEt), difficult to produce by other methods. The structural peculiarities of these compounds were studied in detail by NMR spectroscopy and by XRD analysis (for 6, 9 and 10). The properties of 1-12 were studied by UV/vis and luminescence emission spectroscopy, electrochemistry and DFT calculations, indicating an effective conjugation in their molecules.

4-Oxo-7-fluoro-1,10-phenanthroline-2,9-diamides: Synthesis, Structural Features, Lanthanide Complexes, and Am(III)/Ln(III) Solvent Extraction.

A highly efficient synthetic approach was developed for the synthesis of unsymmetrical 1,10-phenanthroline-2,9-diamides with two different substituents in the fourth and seventh positions of the phenanthroline core. The structures of these ligands were confirmed using various spectral methods including 2D-NMR and X-ray analysis. Quantum chemical calculations supported the presence of tautomeric forms of these ligands.

Rearrangements of the Radical Cations of 3-Aryl-5-fluoroisoxazoles: Further Evidence for Existence of Benzocyclopropenyl Cation.

The fragmentation reaction of the radical cations of 3-aryl-5-fluoroisoxazoles formed via EI-MS is described. A new rearrangement accompanied by fluorine atom migration is discovered. A mechanistic rationale for the rearrangement supporting the existence of a fluorinated benzocyclopropenyl cation was proposed based on the experimental data and quantum chemical calculations.