SYNTHESIS AND CHARACTERIZATION OF OXOVANADIUM(IV) COMPLEXES WITH SACCHARIDES

Oxovanadium(IV) complexes of the monosaccharides D-glucose and D-fruct ose, and the disaccharides sucrose and turanose, were obtained in aque ous solution at pH 12. Their solid sodium salts were precipitated with absolute ethanol and characterized by UV-VIS, IR, and diffuse reflect ance spectroscopies. Magnetic susceptibilities at room temperature wer e also determined. The L:M stoichiometry, as derived from spectrophoto metric titrations, was 2:1 for all saccharides except for the D-fructo se complex, which was 3:1. The analytical and magnetic data also show that in the solid state the complex of this ligand shows a different b ehavior, generating a dinuclear species bridged by a sugar molecule, w hereas all the other complexes are mononuclear. (C) 1997 Elsevier Scie nce Ltd.