Novel method for the synthesis of zirconium(IV) chelate complexes from oxo-zirconium(IV) aryloxides

Abstract

Reaction of oxo-zirconium(IV) aryloxides with the composition ZrO(OAr)₂ and ZrOCl(OAr) [where OAr = OC₆H₄NO₂-4, OC₆H₄Cl-2, and - OC₆H₄(NO₂)₂⁻ 2,4] with chelating ligands such as acetylacetone (acacH), 2-hydroxyacetophenone (hapH) and salicylaldehyde (salH) in Et₂O yield eight coordinate chelate complexes with the composition Zr(acac)₄, Zr(hap)₄ and Zr(sal)₄, as indicated by analytical, physico-chemical and infra-red spectral studies. The conclusive evidence for the formation of these zirconium(IV) chelates, contrary to the expected oxo-zirconium(IV) chelates of composition ZrO(chelate)₂, has been obtained from the crystal structure determination of one of these zirconium(IV) chelates, Zr(acac)₄ using X-ray technique. Present studies have thus provided a new method for the preparation of zirconium(IV) chelate complexes from oxo-zirconium(IV) aryloxides.