OXOVANADIUM(IV) COMPLEXES OF HALOGENATED OXINES

Six VO2+ complexes of 8-hydroxyquinoline (oxine) and of some of its mo no- and dihalogenated derivatives have been prepared. The complex of 5 -chloro-oxine is very unstable and oxidizes rapidly, generating a V(V) complex of stoichiometry VO(QCl)(2)OH which could also be prepared in pure form. The infrared spectra of all complexes have been recorded a nd are discussed in detail. The complexes containing halogenated ligan ds appear as polymeric species, interacting through V=O ... V=O bridge s. The magnetic moments, investigated at room temperature, indicate co mpletely quenched orbital contributions. The analysis of the electroni c spectra reveals very complex solution behaviour including, oxidation phenomena, ligand loss, and interaction with the solvent.