18845

Increasing Potential Redox Reactivity of Group IV Metal Complexes by Characterizing the Unique Equilibrium System of a Catechol-Type Amidophenolate Ligand

Allyson Sia

Mentor: Alan Heyduk

Ligand design offers a method for controlling the reactivity of transition metal complexes. In an extreme example of this control, the choice of a particular ligand may engender wholly unique reactivity to the metal ion. Catechol-type ligands offer such an opportunity since they are redox active and can act as electron reservoirs when coordinated to a metal center. Recently, we have reported new metal-ligand cooperative reactivity built upon the coordination chemistry of the metals titanium, zirconium, and hafnium, and the redox activity of catechol-derived amidophenolate ligands. To better understand this reactivity, we sought a deeper understanding of the fundamental thermodynamic properties of catechol-type molecules through the study of conproportionation equilibria. The position of the equilibrium relates to the relative stability of the catechol molecule in three different oxidation states. This relative stability in turn reflects the ability of each molecule to act as a redox-active ligand upon coordination to a metal center.