Chelation synthetic ligands

Aluminium complexes of chelating amido ligands are perhaps the most common type of monomeric four-coordinate aluminium amide. A full listing of such complexes will not be provided and selected examples will suffice to illustrate synthetic approaches and... 

Most kinetic work is carried out on biomimetic hemins having a chelating imidazole ligand, or a synthetic, tetraaryl porphyrin. A general scheme of reaction is illustrated for an iron porphyrin below [513] where the terminal ligand X is Cl ... 

Although the observed effect of the metal ions on the extent of O-benzoy-lation or C-benzoylation is important for synthetic purposes, it is questionable whether any conclusions of significance to the reactions of chelated organic ligands can be obtained from these results. It would be of great interest to repeat these reactions with the inert chelates of Rh(III), Co (III), Al(III), and Cr(III). 

Cadmium has been used in several experimental studies of metal chelation in sea waters constituted with synthetic ligands such as EDTA (Maljkovic and Branica, 1971) and NTA (Raspor et al., 1977). The conditional stability constants of zinc and cadmium complexes with soil humics and natural water organics are not high (see Table IV). Nevertheless, such interactions have been invoked to explain the enrichment of zinc in marine and estuarine sedimentary pore waters (Elderfield and Hepworth, 1975 Nissenbaum and Swaine, 1976). 

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