Fig. 9: Computed reaction profile for the hypothetical disproportionation of 2Li to 4Li/1/Li+(C6H6)−•.
From: Evidence for ligand- and solvent-induced disproportionation of uranium(IV)
Complex 2Li containing two uranium(IV) ions reacts via transition state Li-TS-dis to give the disproportionation intermediate Li-product-dis where uranium(V) and (III) ions are formed, but this is an endothermic reaction. Spontaneous cleavage of Li-product-dis to two monomer units is clearly disfavoured, as is reaction with toluene to give 4Li, 1, and the lithium toluene radical anion salt. If Li-product-dis formed it would, however, react with benzene to give 4Li, 1, and the lithium toluene radical anion salt. Complex 4Li would then converted to 5Li using the capping agent Me6-Tren.
