Two-Electron Reduction of a U(VI) Complex with Al(C₅Me₅)

The reduction of U­(VI) to U­(IV) is rare, especially in one step, and not observed electrochemically as a one-wave, two-electron couple. Here, we demonstrate that reduction of the uranium­(VI) bis­(imido) complex, (C5Me5)2U­[N­(4-OiPrC6H4)]2, is readily accomplished with Al­(C5Me5), forming the bridging uranium­(IV)/aluminum­(III) imido complex (C5Me5)2U­[μ2-N­(4-OiPrC6H4)]2Al­(C5Me5). The structure and bonding of the bridging imido complex is examined with electrochemical measurements in tandem with density functional theory calculations.