Single Crystal to Single Crystal Transformation and Hydrogen-Atom Transfer upon Oxidation of a Cerium Coordination Compound

Trivalent
and tetravalent cerium compounds of the octamethyltetraazaannulene
(H2omtaa) ligand have been synthesized. Electrochemical
analysis shows a strong thermodynamic preference for the formal cerium­(IV)
oxidation state. Oxidation of the cerium­(III) congener Ce­(Homtaa)­(omtaa)
occurs by hydrogen-atom transfer that includes a single crystal to
single crystal transformation upon exposure to an ambient atmosphere.