Ligated Metal Ions Ligand Exchange

Burgess, Metal Ions in Solution, Ellis Horwood, Chichester, 1978, Chapter 11. F. L. Dickert, Z. Phys. Chem. Frankfurt am Main), 1977, 106, 155. 

The rate law, rate constants, and activation parameters have been obtained for exchange of trifluoroacetate with its dinuclear molybdenum(ii) complex [M02-(OaCCFa). The results are discussed with particular reference to related dimolybdenum and dirhenium metal-metal-bonded compounds. A preliminary report on copper(ii) exchange with copper(ii)-salen complexes gives evidence to support the hypothesis of the intermediacy of dinuclear species.  

studies of ligand exchange involving aminopolycarboxylate ligands include those of egta at calcium(ii) and of edta at magnesiura(ii), calcium(ii), and strontium(ii). The relative importance of dissociative and associative (i.e. via an L—M—L intermediate) paths has been assessed, and the reactivities of variously protonated and deprotonated forms of the ligands and the complexes have been considered. 

Kohler and H. Elias, Inorg. Chim. Acta Lett., 1979, 34, L215. 

One of the most active areas remains that of displacement of di-imine ligands from low-spin iron(ii) complexes by such nucleophiles as cyanide or hydroxide. Argument continues as to whether the mechanisms of such reactions involve initial attack at the iron or at the co-ordinated ligand (giving a Meisenheimer-type intermediate). Discussion of this subject is split between this and the next section. 

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The traditional techniques of metal ion separation and sequestration are precipitation, solvent extraction, and ion exchange. The introduction of multidentate ligand molecules with ligating atoms arranged to define a cation coordination site with a specific size intruded anew selectivity factor to the traditional techniques. The differing... 

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