ИСТИНА

A new type of heterocyclic “hard-and-sof” phosphinoxide-bearing N-heterocycles for f-elements binding was proposed from the basis of DFT simulation (PBE, B3LYP, cc-pVDZ and cc-pVTZ basis sets). Te efcient method for the scalable preparation of the reagents by cross-coupling reactions was developed. As a N-donor scaffold the pyridine, 2,2’-bipyridine and phenanthroline were used and their combination with different dialkyl-, diaryl- or alkylarylphosphinoxides were applied. Te structures of the ligands were estimated by X-Ray. All of the synthesized reagents demonstrate selectivity to Am over Eu on extraction from 0.5-5M nitric acid to polar diluents. For the frst time the signifcant affect of P,P-diasteriomers on extraction was observed for phenanthroline-based reagent. Solvate numbers for the extractants strongly depends on the number of donating atoms and less on their nature. Te model Eu complexes were prepared and structurally characterized for the extractants based on 2,2’-bipyridine and phenanthroline scaffolds. Phosphinoxides based on 2,6-disubstituted pyridine possess the beter among investigated compounds efciency in Am/Cm separation (SFAm/Cm 2.9-3.5 from 0.1-3M HNO3) which was estimated based on three methods γ-, α- and liquid-scintillation spectrometry. Te DTF modeling of the extracting species show that the beter fting of the spatial requirements of the ligand was observed for Am than Cm or Eu . Te reagents demonstrate excellent radiation stability: the γ-radiolysis up to 350kGr doesn’t decrease the Am, Eu and Cm distribution coefcients. So the new generation of neutral organophosphorous reagents are promising for application in minor actinide separation technology.