Reactivity of coordinated ligands

The change in reactivity of ligands as a result of their coordination to a metal center forms the basis for the use of metal complexes as stoichiometric reagents and homogeneous catalysts in organic chemistry. 

The increase in electrophilicity of coordinated ligands commonly leads to more favorable hydrolysis reactions. There are many reports on hydrolysis reactions of coordinated carboxamides, halogenated alkylamines, Schiff bases, thioamides, nitriles, etc. For example, thiourea and thioacetamide complexes of platinum metals decompose on heating in basic solution with formation of the corresponding metal sulfides, Eq. 1.26 and 1.27  

This process has been used for the isolation and concentration of platinum metals as well as their gravimetric determination. 

The presence of the metal-hydroxide group provides additional rate enhancement over coordination to a substitutionally inert Lewis acidic center.55 Cobalt(III) complexes of the type [CoL4(H20)2] have been found to be effective reagents for the hydrolysis of a number of important functional 

This effect promotes decarboxylation and explains the absence of any catalytic effect of the metal ions on decarboxylation of monocarboxylic acids. 

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Redox Reactivity of Coordinated Ligands in Pentacyano(L)Ferrate Complexes Jose A. Olabe... 

REDOX REACTIVITY OF COORDINATED LIGANDS IN PENTACYANO(L)FERRATE COMPLEXES... 

The present volume is a non-thematic issue and includes seven contributions. The first chapter byAndreja Bakac presents a detailed account of the activation of dioxygen by transition metal complexes and the important role of atom transfer and free radical chemistry in aqueous solution. The second contribution comes from Jose Olabe, an expert in the field of pentacyanoferrate complexes, in which he describes the redox reactivity of coordinated ligands in such complexes. The third chapter deals with the activation of carbon dioxide and carbonato complexes as models for carbonic anhydrase, and comes from Anadi Dash and collaborators. This is followed by a contribution from Sasha Ryabov on the transition metal chemistry of glucose oxidase, horseradish peroxidase and related enzymes. In chapter five Alexandra Masarwa and Dan Meyerstein present a detailed report on the properties of transition metal complexes containing metal-carbon bonds in aqueous solution. Ivana Ivanovic and Katarina Andjelkovic describe the importance of hepta-coordination in complexes of 3d transition metals in the subsequent contribution. The final chapter by Sally Brooker and co-workers is devoted to the application of lanthanide complexes as luminescent biolabels, an exciting new area of development. 

The catalytic activity of organic 38 and metallo-organic compounds (134) in heterogeneous systems Reactivity of coordinated ligands 21 and homogeneous catalysis (42)... 

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