Synthesis, characterization and thermal decomposition of dioxouranium(VI) complexes with N,N-diarylidene-S-propyl-thiosemicarbazone: Crystal structure of [UO2(L)(C4H9OH)]

Reactions of salicyl- and 3,5-dichlorosalicylaldehyde-S-propyl-thiosemicarbazones with salicyl- and 3,5-dichlorosalicylaldehyde in the presence of UO₂(CH₃COO)₂ in different alcohols yielded stable solid complexes corresponding to the general formula UO₂(L)ROH] (R: propyl-, butyl-, pentyl-, and octyl-). The complexes were characterized by means of elemental analysis, IR and ¹H NMR spectroscopies. The thermal stabilities of the alcohol solvated complexes were investigated in air and nitrogen atm., and determined their decomposition phases. In the crystal structure of the UO₂(L)(C₄H₉OH)], the U(VI) centre is seven-coordinated in a distorted pentagonal bipyramidal geometry involving O,O,N,N atoms of two phenolic and two imine groups and one oxygen atom of alcohol molecule in basal plane and two O atoms of dioxo group in apical positions. The title structure is stabilized by one intramolecular interaction of types C-H?Cl and by two intermolecular interactions of types O-H?O and C-H?π (benzene) leading to the molecular chain along the 0 1 0] direction.