Transition-metal derivatives nucleophilic cleavage reactions

Reactions with Soft Bases. Metal-metal bonds are often weaker than those the same metal can form with ligands. Thus the reaction of clusters with nucleophiles frequently leads to cleavage of metal-metal bonds and to cluster breakdown. The normally low oxidation state of metal centers on clusters makes their reaction with soft bases such as CO, PR3, olefins etc. very favorable. Clusters of lighter transition metals undergo mainly fragmentation reactions. Heavier element derivatives however are likely to participate in addition and substitution reactions. 

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