Complexes of thorium(IV) and uranium(IV) with some Schiff bases

Complexes of thorium(IV) and uranium(IV) with Schiff bases derived from salicylaldehyde have been prepared and characterised. The metal tetrachlorides react directly with quadridentate Schiff bases in ethanol to yield the complexes but bidentate Schiff bases yield hydrolysed products under the same conditions. Complexes of the bidentate Schiff bases are obtained by reaction of ligand with metal tetraacetate in a melt or by ligand exchange with the thallium-Schiff base complex. Absorption spectra are reported and band assignments are discussed. (author)