Thermal decomposition studies of furfural-based Schiff base complexes of uranyl halides and pseudohalides

Abstract

The bidentate Schiff base ligand (NO donor set), furfurylidene arylamine (L), prepared by reaction in situ of furfural and aromatic amine (1:1) in EtOH, reacts with UO 2X 2 (X = Cl, NCS) to form red, diamagnetic complexes of the type [UO 2(L) 3X 2], which are non-electrolytic and ten-coordinated. Analytical data and IR spectra characterise the complexes. Thermal decomposition studies of these dioxouranium(VI) complexes have been made and the stoichiometries of the intermediate species and the mechanism of their formation have been discussed. All these complexes remain thermally stable at least up to ca. 150°C and thereafter lose the ligand molecules in several steps finally forming U 3O 8 above 750–800°C.