Studies on some thorium(IV) complexes with high coordination numbers derived from semicarbazones of 4-aminoantipyrine

The interaction of thorium(IV) salts with 4 [N-(benzylidene)amino] antipyrine semicarbazone (BAAPS), 4[N-(4-methoxybenzylidene)amino] antipyrine semicarbazone (MBAAPS), 4[N-(4'-dimethoxyaminobenzylidene)amino]antipyrine semicarbazone (DABAAPS), 4[N-(2'-nitrobenzylidene)amino]antipyrine semicarbazone (2'-NO(2)BAAPS), and 4[N-(3'-nitrobenzylidene)amino]antipyrine semicarbazone (3-NO(2)BAAPS) in non-aqueous solvents resulted in the formation of [ThL2X4] (N = Cl, Br, or NCS), [ThL2I2]I-2, [ThL2](ClO4)(2) or [ThL(NO3)(4)] (L = BAAPS, MBAAPS, DABAAPS, 2-NO(2)BAAPS, or 3-NO(2)BAAPS). All of these compounds were characterized by elemental analyses, electrical conductivity, IR, and thermal methods. X-ray powder diffraction studies of a representative complex were also undertaken. Th(IV) displays the coordination numbers 6, 8, 10, and 11 in these compounds depending on the nature of the coordinated anion and the stoichiometry.