Ligand-Assisted Dechelation

Of course, when highly dentated ligands have to be replaced, more complicated behavior is observed. In this category, are the well-studied ligand exchange reactions of edta and polyamine complexes, a typical one of which (charges omitted) is 

This may be studied in either direction by adjusting the pH and reactant concentrations. Substantial evidence exists for a mechanism in which three nitrogen atoms of the polyamine bind to the metal (10) before the rds of M-N eleavage, which leads to the final products. See also Refs. 17 and 119. 

The incoming ligand (or metal ion in the previous section) simulates H+ by preventing reclosing of the Ni-donor bonds as these are successively broken (see also Fig. 8.7) 

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