Organically templated uranium(iv) fluorooxalates with layer structures: (H4TREN)[U2F6(C2O4)3]·4H2O (TREN = tris(2-aminoethyl)amine) and (H4APPIP)[U2F6(C2O4)3]·4H2O (APPIP = 1,4-bis(3-amino-propyl)piperazine)

Abstract

Two organically-templated layered uranium(IV) fluorooxalates, (H₄TREN)[U₂F₆(C₂O₄)₃]·4H₂O (1) (TREN = tris(2-aminoethyl)amine) and (H₄APPIP)[U₂F₆(C₂O₄)₃]·4H₂O (2) (APPIP = 1,4-bis(3-aminopropyl)piperazine), have been synthesized by hydrothermal methods and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and magnetic susceptibility. Both structures consist of anionic [U₂F₆(C₂O₄)₃]⁴⁻ layers separated by organic ammonium cations and lattice water molecules. The UF₃O₆ polyhedra are connected by oxalate ligands in different ways within the layers. They are the first examples of organically-templated uranium fluorooxalates. Crystal data for compound 1 follow: monoclinic, P2₁/c (No. 14), a = 19.1563(5) Å, b = 8.9531(2) Å, c = 16.6221(4) Å, β = 114.633(1)°, and Z = 4. Crystal data for compound 2 are the same as those for 1 except a = 10.3309(8) Å, b = 15.564(1) Å, c = 17.537(1) Å, and β = 95.430(4)°.