[en] Recently some uranium tetrachloride adducts with N-(hydroxyphenyl)-salicylaldimine and N-(methoxyphenyl)salicylaldimine have been prepared (Doretti et al., J. Inorg. Nucl. Chem., (in press)): the study has now extended to the complexes of Uranium(IV) and Thorium(IV) with N,N'-Ethylenebis(salicylideneimine), H₂salen, and N,N'-Propylenebis(salicylideneimine), H₂salpropen, with the aim to prepare fully substituted complexes, mixed complexes containing both chloride and Schiff base groups and adducts of tetrachlorides with free Schiff bases. This paper reports the preparation and properties of the compounds MCl₄(H₂salen), MCl₄(H₂salpropen), M(salen)Cl₂, M(salen)₂ and M(salpropen)₂, where M = U or Th. These compounds have been characterized by elemental analyses and their IR spectra are reported and discussed. (author)