The Synthesis Of The Multiple Vanadium-oxygen Compounds, Structural And Physicochemical Characterization,

With the discovery of vanadium haloperoxidases and nitrogenase, much more interests have been concentrated on the coordination and the bioinorganic characteristics of vanadium compouds. Many oxovanadium (IV) complexes have the potential insulin-mimetic effects and have been reganded as the one kind of inorganic drug to cure diabetes. The studies of the vanadium coordination and bioinorganic chemistry have developed extensively in recent years. The following are the study results in this work.1. Four novel quaternary vanadium complexes with carboxylic acid, acac and phen or 2,2'-bipy, VO(acac)LL'(L = Phen, L'= Fta (1), SMIA (2), MNBA (3); L = 2,2'-bipy, L'= MBBA(4) were synthesized and characterized by single crystal X-ray diffraction. The central vanadyl ion is in a distorted octahedral VO4N2 environment. The complexes were characterized by IR, CV and EPR spectroscopy, and the factors affecting the synthesis of the quaternary complexes were also discussed. Hexanuclear- and dioxo- vanadium compounds, [(phen)4V6O12(MeOH)4]·MOH·H2O (5) and VO2(acac)(phen) (6),were isolated from the reaction system with the addition of animo acid ligands.2. One oxovanadium (IV) compound [VO(OX)(dibim)].CH3OH (7) was synthesized by the reaction of VO(acac)2, OX and dibim ligands, and characterized by X-ray crystallography, IR and EPR.3. One unexpected vanadium compounds VO(Cyclic-Btc)(EtOH)2 (8) was obtained from the reaction system of VO(acac)2 and Btc ligand in ethanol, where Cyclic-Btc was resulted from the cyclization of Btc in the synthesis process. X-ray crystallography revealed that complex 8 contains a thiadiazole ring and X-band EPR spectroscopy of the sample indicated the existence of vanadium (IV) ions in the compound.