Browsing by Author "McCleverty, Jon A."

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    Formation of trimetallic complexes containing redox-active nitrosyl molybdenum tris(3,5-dimethylpyrazolyl)-borato groups. Schiff base compounds containing two Mo and one Cu centre
    (Elsevier, 1994) Kagwanja, Stanley M.; Jones, Christopher J.; Maher, John P.; McCleverty, Jon A.
    The reaction of [Mo(NO)Tp*Cl2] [Tp* = tris(3,5-dimethylpyrazolyl)borate] with copper(II) Schiff base complexes derived by condensation of two mole equivalents of 2,5-dihydroxybenzaldehyde with α,ω-diamines [1,2-C6H4(NH2)2, NH2(CH2)nNH2, n = 2–5] affords trimetallic species containing three potential redox centres. The IR, UV-vis and EPR spectroscopic properties of these compounds are described and it is shown that, with increasing chain length in the diimino bridges of the Schiff base complexes, there are small distortions from planarity, probably towards tetrahedral structures. From cyclic and differential pulse voltammetry it is shown that the trimetallic species primarily undergo two accessible sequential one-electron reductions associated with the {Mo(NO)Tp*Cl} centres, and by determination of conproportionation constants for the mono-reduced species, it is established that there is weak interaction between these two centres. Attempts to obtain reduced trimetallic species are described.
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    Trimetallic complexes containing Nickel or Palladium and two Molybdenum nitrosyl groups
    (1997) Kagwanja, Stanley M.; Johns, Christopher J.; McCleverty, Jon A.
    The reaction of [Mo(NO){HB(dmpz)3}Cl2] [HB(dmpz)3 = tris(3,5-dimethylpyrazolyborate] with nickel(II) and palladium(II) Schiff-base complexes derived by condensation of two mole equivalents of 2,5-dihydroxybenzaldehyde with α,ω-diamines [1,2-C6H4(NH)2),(CH2)nNH2, n = 2–4 for Ni, n = 2 for Pd) affords trimetallic species. From cyclic, square wave and differential pulse voltammetric data it is shown that the species may be reduced to a dianion and that the sites of reduction are probably the two molybdenum nitrosyl fragments. From the electrochemical and limited EPR spectral data obtained from reduced species, it is clear that there is very weak electronic and minimal magnetic interaction between the redox centres.