Preparation, characterization and reactivity of vanadyl (IV) and uranyl (VI) complexes with triketones and ketophenols

Some ?,?-triketones and ?-diketophenols have been prepared and characterized. A series of mononuclear oxovanadium(IV) adducts with these ligands have been isolated and characterized. All these mononuclear complexes have a free coordination set and may act as ligands towards a second metal ion. The syntheses of dinuclear complexes using the mononuclear ones as ligands are reported. Their stereochemistry is discussed on the basis of ir, uv and magnetic data. Mono- and dinuclear complexes were tested as ethylene-propylene copolymerization catalysts.