Properties of Some Compounds of the Metals of Medium Atomic Weight with Heterocyclic Ligands and the more readily Polarized Anions

  • B.G. Naik

    Student thesis: Doctoral ThesisDoctor of Philosophy


    Part I
    The coordination behaviour of 2-benzoylpyridine (PhCOpy )
    with some transition metal cations was investigated. 2-benzoylpyridine
    is believed to be a weak-field, bidentate (NO-co-ordination) ligand.
    Complexes of 2-benzoylpyridine with the perchlorates, chlorides,
    bromides and iodides of manganese (II), cobalt (II) and nickel (II)
    are described. Some compounds of zinc (II), cadmium (II) and
    magnesium (TI) were studied for comparison. With the exception of
    Mn (PhCOpy )X_ (X = Cl or Br) and Cd(PhCOpy) C15, all compounds
    isolated were bis-complexes but the metal ions are six-co-ordinate
    in all cases.

    The complexes, [Nn (PhCOpy){EtOH) 9] (C104 )o3
    [Co(PhCOpy), (OH) 9] (C10, )o and [Ni (PhCOpy), (EtOH) 9] (C104) with
    ionic perchlorate groups, and [Co(PhCOpy) (C104) 9] and
    [Ni(PhCOpy), (C104) 9] with weakly coordinated perchlorate groups
    were characterised. In nitromethane, it was established that -
    [Co(PhCOpy ) Xo] (X = Cl or Br) dissociates to the pseudo-tetrahedral
    complex, [Co(PhCOpy )X.] . The two forms of Ni (PhCOpy ) C1,
    are believed to be the two isomers of the trans-dichloro-complex.
    [Mn(PhCOpy)X,] (X = C1 or Br) and [Cd(PhCOpy )C1.] are polymeric.
    The compounds M(PhCOpy oly. (M = Co, Ni, Zn or Cd) are isomorphous
    and form isomorphous groups with M(PhCOpy)oClo.
    {KM = Co, Ni(green and yellow)].

    Part II
    The compounds investigated have al] been of one or the
    other of two types, namely [(pyridine base), (M)2*(13)] (M = first row divalent transition metal ion) or [(pyridine base),
    (wr ys* (CNSTy)o] »(M' = Ni(II)) only and pyridine base = pu iine
    B-picoline or y-picoline in both cases. Some I, compounds of
    manganese (II), iron (11), cobalt (II) and cadmium (11) with pyridine
    bases were crystallised from acetonitrile. Acetonitrile was retained
    as an uncoordinated, lattice component. W'? (B-picoline)(13)9
    (M = Fe, Mn or Cd) could not be crystallised.

    Little information concerning the structure of the above
    compounds was obtained from physical examinations. The most
    informative data was derived from the measurement of the magnetic
    susceptibilities. High-spin octahedral complexes, [M(pyridine base),
    (15) 9] (M = Mn, Fe or Co) and planar or "tetragonally distorted
    octahedral" nickel (II) complexes, Ni(pyridine base )X [X = I, or
    (NCS-I5) J were characterised. Study of the magnetic susceptibilities
    at various temperatures is described for nickel (11) complexes only.
    The bonding nature of (CNS-I5) , as Ni-NCS-I, is discussed.

    The compounds Cd(py)a(13)o5 Cd(y-pic)a(I3)o 2(CH2CN) , and
    the polymerisation reactions involved in cadmium - y-picoline-iodine
    are described.

    The conductivity study of all compounds in nitromethane and
    in dimethylsulphoxide, and the absorption spectra of 13 ions in
    acetonitrile and in 1,2-dichloroethane are described.
    Date of Award1972
    Original languageEnglish


    • chemistry
    • metal compounds
    • metals
    • atomic weight
    • heterocyclic ligands
    • polarised anions
    • polarized anions

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