Complexes of ambiphilic ligands: reactivity and catalytic applications

Since the mid 2000's, the incorporation of Lewis acid moieties in ligands for transition metals has been studied extensively. So-called ambiphilic ligands were shown to possess rich and unusual coordination properties and special focus was given to the coordination of Lewis acids as σ-acceptor ligands (concept of Z-type ligands). Recent studies have demonstrated that the presence of Lewis acids at or nearby transition metals can also strongly impact their reactivity. These results are surveyed in this review. The stoichiometric transformations and catalytic applications of complexes deriving from ambiphilic ligands are presented. The different roles the Lewis acid can play are discussed. This review focuses on the way Lewis acids of ambiphilic ligands influence the reactivity of transition metal complexes and on the new perspectives this opens in catalysis.