Time-controlled synthesis of the 3D coordination polymer U(1,2,3-Hbtc) followed by the formation of molecular poly-oxo cluster {U} containing hemimellitate uranium(iv).

Two coordination compounds bearing tetravalent uranium were synthesized in the presence of tritopic hemimellitic acid in acetonitrile with a controlled amount of water (HO/U ≈ 8) and structurally characterized. Compound 1, [U(1,2,3-Hbtc)]·0.5CHCN is constructed around an eight-fold coordinated uranium cationic unit [UO] linked by the poly-carboxylate ligands to form dimeric subunits, which are further connected to form infinite corrugated ribbons and a three-dimensional framework.

Uranyl Cation Incorporation in the [PWO] Macrocycle Phosphopolytungstate.

Association of uranyl nitrate with the macrocycle [PWO] in formate buffered aqueous solution leads to the formation of a new compound (KLiNa)[(UO)(HCOO)(PWO)Cl]·89HO (1). Its characterization by XRD reveals a high disorder of the uranyl cations and the formation of monodimensional chains of anionic [(UO)(HCOO)(PWO)Cl] entities linked through formate ligands. The uranyl species are located either in the coordinating sites of the macrocycle [PWO] or at its surface.