Facile Dinitrogen and Dioxygen Cleavage by a Uranium(III) Complex: Cooperativity Between the Non‐Innocent Ligand and the Uranium Center

Abstract

Activation of dinitrogen (N 2 ,7 8%)a nd dioxygen (O 2 ,2 1%)h as fascinated chemists and biochemists for decades.T he industrial conversion of N 2 into ammonia requires extremely high temperatures and pressures.H erein we report the first example of N 2 and O 2 cleavage by auranium complex, [N(CH 2 CH 2 NP i Pr 2) 3 U] 2 (TMEDA), under ambient conditions without an external reducing agent. The N 2 triple bond breaking implies aU III-P III six-electron reduction. The hydrolysis of the N 2 reduction product allows the formation of ammonia or nitrogen-containing organic compounds.T he interaction between U III and P III in this molecule allows an eight-electron reduction of two O 2 molecules.T his study establishes that the combination of uranium and al ow-valent nonmetal is ap romising strategy to achieve af ull N 2 and O 2 cleavage under ambient conditions,w hichm ay aid the design of new systems for small molecules activation.

Selective hydroboration of terminal alkynes catalyzed by heterometallic clusters with uranium–metal triple bonds

“…The intense absorption bands in the UV-vis region and relatively weak absorption bands in the NIR for these complexes compare well with the reported results for U(IV) complexes. [59][60][61] Mo ¨ssbauer spectroscopy To investigate the oxidation state of Fe in complexes 4 and 5, the zero-field 57 Fe Mo ¨ssbauer spectra of 4 and 5 were measured at 80 K on crystalline samples and feature single quadrupole doublets (Figures 4A and 4B). To the best of our knowledge, no 57 Fe Mo ¨ssbauer data of UÀFe derivatives have been reported, thus a comparison of the isomer shift of 4 with other U-Fe systems is unavailable.…”

Uranium(III)–Phosphorus(III) Synergistic Activation of White Phosphorus and Arsenic

“…[6][7][8][9] Several breakthroughs of N 2 activation by well-defined uranium complexes have emerged in recent years. [10][11][12][13][14][15][16][17][18][19] In contrast to N 2 activation, the activation of the heavier congeners, such as white phosphorus (P 4 ) and elemental arsenic, by molecular uranium complexes are exceptionally rare, [20][21][22][23][24] which presumably due to the hard-soft mismatch between uranium and phosphorus or arsenic. Indeed, there is no example of uranium-mediated activation of elemental arsenic to our knowledge.…”

“…The U-N bond lengths in 3 are consistent with the reported U(IV) species containing this N 4 P 3 ligand. 19,73,78 The bond lengths for U1-P1 (3.110(2) Å) and U1-P2 (3.0284(18) Å) in complex 3…”

Dinitrogen Cleavage and Hydrogenation to Ammonia with a Uranium Complex

“…To further investigate the conversion of 1 to 3, density functional theory (DFT) calculations were carried out using the B3PW91 functional that have been proved to be reliable in dealing with such systems. [32][33][34] Dispersion corrections were considered and appeared to be small in this case (Figs. S28 and S29).…”