Uranyl(VI) and lanthanum(III) thio-diglycolamides complexes: Synthesis and structural studies involving nitrate complexation

New tri-functional ligands of the type R2NCOCH2SCH2CONR2 (where R = iso-propyl, n-butyl or iso-butyl) were prepared and characterized. The coordination chemistry of these ligands with uranyl and lanthanum(III) nitrates was studied by using the IR, 1HNMR and elemental analysis methods. Structures for the compounds [UO2(NO3)2(iPr2NCOCH2SCH2CONiPr2)] [UO2(NO3)2(iBu2NCOCH2SCH2CONiBu2)], [La(NO3)3(iPr2NCOCH2SCH2CONiPr2)2] and [La(NO3)3(iBu2NCOCH2SCH2CONiBu2)2] were determined by single crystal X-ray diffraction. These structures show that the ligand acts as a bidentate chelating ligand and bonds through both the carbamoyl groups to the uranyl and lanthanum(III) nitrate groups. Solvent extraction studies show that the ligand can extract the uranyl ion from the nitric acid medium but does not show any ability to extract the americium (III) ion.

New tri-functional ligands of the type R2NCOCH2SCH2CONR2 (R = iso-propyl, n-butyl or iso-butyl) were prepared and their coordination chemistry with the uranyl and lanthanum(III) nitrates has been established. The structures of the uranyl and lanthanum(III) nitrates show the chelating mode of bonding for these ligands in the solid state. Solvent extraction studies show that the ligand can extract the uranyl ion from nitric acid medium but does not show any ability to extract the americium(III) ion.Figure optionsDownload as PowerPoint slide