Catechol ligands, redox activity

Such a complex is constituted not only by the redox-active V(IV) centre, but also by the redox-active catecholate ligand. In fact, as we will see in more detail in Chapter 6, Section 3, o-dioxolene ligands can undergo the redox processes illustrated in Scheme 4. 

These complexes combine a central metal in a high oxidation state with a redox active ligand (catechol). This combination arises from the idea that the electronic perturbation induced in the metal complex by reaction with dioxygen can discharge itself ... 

In the present paper we would like to present the results of synthetic experiments on semiquinone and catechol complexes of copper, with characterization that may provide insights on the extent to which redox activity at both the metal and the quinone ligand contributes to the synthetic course of oxidation reactions with dioxygen. 

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