Browsing by Author "Johns, Christopher J."

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    Reaction of molybdenum mononitrosyl halides with Schiff bases: Hydrolysis of azomethine links,formation of monometallic tris
    (Elsevier, 1996-06) Kagwanja, Stanley M.; Jeffery, John C.; Johns, Christopher J.; McCleverty, John A.
    The reaction of 2 mol equiv. of [Mo(NO){HB(dmpz)3}X2] ((HBdmpz)3 = tris(3,5-dimethylpyrazolyl)borate; X = Cl or I) with Schiff base ligands derived by condensation of 2 mol equiv. of para- and meta-hydroxybenzaldehyde with 1,4-C6H4(NH2)2 and 1,6-NH2(CH2)6NH2 afforded monometallic complexes [Mo(NO) {H(dmpz3)} X(OC6H4 CHO)]. Sodium borohydride reduction of the Schiff bases obtained from the hydroxybenzaldehydes and 1,4-C6H4(NH2)2 followed by reaction with [Mo(NO){HB(dmpz)3 Cl2}] afforded the bimetallic species [{Mo(NO)HB(dmpz)3}Cl{(OC6H4CH2NH)2C6H4}]. These compounds were characterized spectroscopically and the structure of a closely related compound, [Mo(NO){HB(dmpz)3}Cl{OC6H3(3-CHO)(4-OH)}], has been determined crystallographically.
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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.