Transmetalation
of the β-diketiminate salt [M][MenacnacPh] (M+ = Na or K; MenacnacPh– = {PhNC(CH3)}2CH–) with
UI3(THF)4 resulted in the formation of the homoleptic,
octahedral complex [U(MenacnacPh)3] (1). Green colored 1 was fully characterized
by a solid-state X-ray diffraction analysis and a combination of UV/vis/NIR,
NMR, and EPR spectroscopic studies as well as solid-state SQUID magnetization
studies and density functional theory calculations. Electrochemical
studies of 1 revealed this species to possess two anodic
waves for the U(III/IV) and U(IV/V) redox couples, with the former
being chemically accessible. Using mild oxidants, such as [CoCp2][PF6] or [FeCp2][Al{OC(CF3)3}4], yields the discrete salts [1][A] (A = PF6
–, Al{OC(CF3)3}4
–), whereas the anion exchange
of [1][PF
6
] with
NaBPh4 yields [1][BPh
4
].