Reversible Dihydrogen Activation and Hydride Transfer by a Uranium Nitride Complex.

Cleavage of dihydrogen is an important step in the industrial and enzymatic transformation of N into ammonia. The reversible cleavage of dihydrogen was achieved under mild conditions (room temperature and 1 atmosphere of H ) by the molecular uranium nitride complex, [Cs{U(OSi(O Bu) ) } (μ-N)] 1, leading to a rare hydride-imide bridged diuranium(IV) complex, [Cs{U(OSi(O Bu) ) } (μ-H)(μ-NH)], 2 that slowly releases H under vacuum. This complex is highly reactive and quickly transfers hydride to acetonitrile and carbon dioxide at room temperature, affording the ketimide- and formate-bridged U species [Cs{U(OSi(O Bu) ) } (μ-NH)(μ-CH CHN)], 3 and [Cs{U(OSi(O Bu) ) } (μ-HCOO)(μ-NHCOO)], 4.