Coordination and separation studies of the uranyl ion with iso-butyramide based ligands: Synthesis and structures of [UO2(NO3)2(iC3H7CON{iC4H9}2)2] and [UO2(C6H5COCHCOC6H5)2(iC3H7CON{iC3H7}2)]

The coordination chemistry of iso-butyramide based ligands such as: iC3H7CON(iC3H7)2, iC3H7CON(C4H9)2 and iC3H7CON(iC4H9)2 with [UO2(NO3)2 · 6H2O], [UO2(OO)2 · 2H2O] {where OO = C4H3SCOCHCOCF3 (TTA), C6H5COCHCOCF3 (BTA) and C6H5COCHCOC6H5 (DBM)}, [Th(NO3)4 · 6H2O] and [La(NO3)3 · 6H2O] has been evaluated. Structures for the compounds [UO2(NO3)2(iC3H7CON{iC4H9}2)2] and [UO2(C6H5COCHCOC6H5)2(iC3H7CON{iC3H7}2)] have been determined by single crystal X-ray diffraction methods. Preliminary separation studies from nitric acid medium using the amide iC3H7CON(iC4H9)2 with U(VI), Th(IV) and La(III) ions showed the selective precipitation of uranyl ion from the mixture. Thermal study of the compound [UO2(NO3)2(iC3H7CON(iC4H9)2)2] in air revealed that the ligands can be destroyed completely on incineration.

Graphical abstractCoordination studies of iso-butyramide based ligands show that they form 2:1 and 1:1 compounds respectively with the uranyl nitrate and uranyl bis(β-diketonates). These ligands act as monodentate ligand and bond through the carbamoyl oxygen atom to the uranyl moiety. These ligands can selectively precipitate uranyl ion from the mixture containing other ions such as thorium(IV) and lanthanum(III).Figure optionsDownload full-size imageDownload as PowerPoint slide