SYNTHESIS, CHARACTERIZATION AND REACTIVITY OF SOME NOVEL DINUCLEAR MIXED-LIGAND PEROXOURANIUM(VI) COMPLEXES

摘要

Novel anionic dinuclear mixed-ligand peroxo complexes of the type [(UO2)(2)(O-2)(3)L(H2O)(2)](3-) (L = Histidinate, aspartate, salicylate, Imidazolate and glutamate) have been synthesised from the interaction of uranyl ion (UO22+) with peroxide (O-2(2-)) in the presence of the respective coligand (L) at pH 9-10. The sparingly soluble complexes were characterized by elemental analyses, FT-IR, laser Raman (LR) and UV-vis spectroscopy and solution electrical conductance measurements. Based on these studies, a double bridged dinuclear structure involving one peroxo and the mixed ligand L (via-COO-) has been tentatively proposed. Infra-red coupled with LR spectra evidenced structurally different metal bound peroxides (eta(2) and sigma:sigma). An aqueous solution of the salicylate and aspartate complexes have been shown to convert triphenylphosphine (PPh3), cyclohexene, styrene and SO2 to the corresponding OPPh3, 1,2 cyclohexanediol, phenylethyleneglycol and SO42-, respectively. (C) 1997 Elsevier Science Ltd. [References: 29]