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The preparation is reported of a series of metal(II) complexes of a quinquidentate ligand produced in situ or by complexation with the Schiff-base condensation-product of two moles of 2-acetylpyridine with 3,3′-iminobispropylamine. From the in situ synthesis of the Ni(II) compound only a quadridentate, mono-Schiff-base complex with coordinated acetyl-pyridine is isolable. The effect of varying the triamine used in this preparation is described and rationalised by consideration of ligand-strain, the effect of stability-constants on ligand-dissociation, and the influence of the acetyl(as opposed to a formyl-) group. Analytical data, infra-red studies, magnetic moments and solution-spectra of the complexes are described, and the interconversion of the two types of Ni(II) complex investigated.

We have used a titrimetric to study the rates of hydrolysis of a series of acetates R 3 MOAc (M = S or Ge; R = Ph, iPr, nPr, c-hex) in dioxane. The effects of the concentration of water, temperature and catalysis by potassium acetate have been studied and are discussed in terms of the proposed mechanism for the hydrolysis, in which bond-breaking processes appear to be important. High orders in the water concentration are observed and the germanium acetates are much more reactive than the silicon acetates.

The preparation and physical properties of a number of complexes formed between divalent nickel and aromatic diazo compounds of type (substituted phenyl)-azo-2-naphthol are described. The abnormal magnetic moment of these complexes in the solid state is explained in terms of incorporation of water to give six-coordinated molecules. Experimental evidence in support of this hypothesis has been obtained by the use of X-ray, magnetic, and infrared spectroscopic methods.

The series of compounds (n−Pr) 3 MO.CO.CH (3−n) Me n M = Si and Ge = O to 3) were prepared and the rates of hydrolysis measured in aqueous dioxane. The entropy of activation is shown to be the main factor determining the rate differences. pK a Values of the substituted acetic acids correlate well with log(k 1 ). A transition state similar to a solvated proton and a solvated carboxylate ion is proposed.