Octakis(tert-butoxo)dicerium(IV) [Ce2(OtBu)8]: Synthesis, Characterization, Decomposition, and Reactivity

An advanced synthesis for the homometallic derivative [Ce-2((OBu)-Bu-t)(8)] (1) starting from [Ce((OBu)-Bu-t)(2){N(SiMe3)(2)}(2)] was developed. Structural characterization of a cerium(IV) complex and its decomposition products confirmed the coexistence of both ether elimination and Ce-O bond cleavage processes, which lead to the formation of [Ce3O((OBu)-Bu-t)(10)] and [Ce-3((OBu)-Bu-t)(11)] (2) derivatives, respectively. Variable-temperature NMR spectroscopy under strict exclusion of moisture enabled insight into the decomposition processes in noncoordinating solvents and at elevated temperature. In addition, structural analysis of the heterovalent 2 and of two new complexes of the general formula [Ce-2((OBu)-Bu-t)(8)(L)] [L = (HOBu)-Bu-t (3), OCPh2 (4)] is described.