The n.m.r. spectra of the isoleptic complexes M(C3H5), ( M = Ni, Pd. Pt) and M(C,Hd4 ( M = Zr, Hf) are reported.The nickel, palladium, and zirconium complexes all give, a t sufficiently low temperatures, spectra corresponding to structures with equivalent symmetrically bonded n-allylic ligands in which rotation of the CH, groups is absent or slow. The nickel and palladium complexes each consist of two isomers of this type in equilibrium. At higher temperatures the spectra of the zirconium and palladium complexes undergo changes corresponding to increased internal rotation of the CH, groups. The hafnium complex has a spectrum corresponding to rapid internal rotation throughout the temperature range studied. The platinum complex gives a spectrum which is best interpreted by assuming that both allylic ligands are equivalent, but each is unsymmetrically bonded to the metal atom.The mass spectra of the isoleptic complexes studied all show parent ions. The degree of fragmentation is very small under field-ionisation conditions but much more extensive under electron impact, and differences in fragmentation patterns are discussed. Polymer Laboratory, P.O. Box 11, The Heath, Runcorn, Cheshire * We use the term isoleptic to indicate that all the Iigands attached to the central metal atom are identical in constitution.
By s. O'BRIEN and D. c. c, SMITH.and syntheses of its hitherto unknown oxygen (11) and nitrogen (111) analogue, are described. Also substituted derivatives of l-oxaphenalene, and other compounds having the ring systems ( 11) and ( 111), are prepared.
A new synthesis of l-thiaphenalene (I)CURRENT interest in +eri-condensed aromatic compounds led us to devise syntheses of compounds having the tricyclic nuclei (I) (11), and (111). These heterocyclic compounds are structurally related to phenalene (IV), a hydrocarbon which forms salts with strong bases, analogously to indene.l Hence there are grounds for expecting that compounds (I : X = S ) (11: X = O )
The nature and extent of the reactions involved in the two-step, wet-fixation durablepress process of Getchell and other processes have been determined by means of a periodate oxidation method. The wet-fixation, durable-press process is shown to differ from the acid colloid process and other wet-fixation procedures. The variations show up in terms of the concentration of the methoxymethylol compound and reactant fixed on the fiber and the extent to which covalent crosslinking of cellulose occurs.The results indicate that in the wet-fixation, durable-press process the methoxymethylmelamine results in only a relatively low degree of cross-linking, but it is, nevertheless, durably fixed to the fabric, probably as a low molecular-weight polymer. It also appears to interact with and moderate the strong cross-linking tendency of the reactant. Predrying the fabric before wet-fixation leads to a greater degree of crosslinking. The nature of the reactant influences the results obtained. The degree of methoxymethylation of the melamine compound also has an effect on the final result which appears to be related to the ability of the methoxymethylmelamine to resist the rinsing (neutralization) step after wet fixation which, in turn, appears to be related to the tendency of the various methoxymethylmelamines to form low polymers.
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