Synthesis and Characterization of 2,2-Biimidazole Complexes of Oxocations of Molybdenum (VI,V) and Uranium(VI) |
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Authors: | Samir S. Kandil Loutfy H. Madkour |
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Affiliation: | Chemistry Department, Faculty of Sciences , Tanta University , Tanta, EGYPT |
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Abstract: | Abstract 2,2′-Biimidazole complexes of MoO2 +2, MoO2 + and UO2 +2 have been prepared and characterized by elemental analysis, conductance; and 1H NMR, IR and electronic spectra. Two types of complexes have been identified. Those obtained from slightly acidic solutions have the formulae MoO2 (H2bim)Cl2.2H2O 1, UO2(H2bim) (Ac)2 2 and UO2(H2bim)Cl2.2H2O 3; whereas those from alkaline solutions have the formulae Mo2O4(Hbim)2.2H2O 4, and MO2(Hbim)2 (M = Mo(VI) 5, U(VI) 6). The infrared spectra of these complexes show characteristic biimidazole frequencies in the 3200–2500, 1550–1000 and 750 cm?1 regions as well as metal oxygen double bonds in the 900 cm?1 region. The stoichiometries of the acetate complex has been confirmed from 1H NMR signal ratios of bimidazole to acetate protons at 7.3 and 2.3 ppm, respectively. The electronic spectrum of molybdenum(V) complex showed d-d transition band at ?13,500 cm?1 in accord with that reported for copper (d9) imidazole complexes; as well as peaks due to charge transfer bands at 30,000–26,000 cm?1 Peaks assignable to BIM → U(VI) were located at ?26,600 cm?1. The most probable structures of these complexes have been suggested. |
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Keywords: | The interacting boson approximation the SU(3) limit PHINT parameters. B(E2) transition rates |
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