Barluzzi Luciano, Chatelain Lucile, Fadaei-Tirani Farzaneh, Zivkovic Ivica, Mazzanti Marinella
Institut des Sciences et Ingénierie Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland . Email:
Laboratory for Quantum Magnetism , Institute of Physics , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland.
Chem Sci. 2019 Feb 18;10(12):3543-3555. doi: 10.1039/c8sc05721d. eCollection 2019 Mar 28.
Uranium nitride complexes are of high interest because of their ability to effect dinitrogen reduction and functionalization and to promote magnetic communication, but studies of their properties and reactivity remain rare. Here we have prepared in 73% yield the diuranium(v) bis-nitride complex [K{U(OSi(O Bu))}], , from the thermal decomposition of the nitride-, azide-bridged diuranium(iv) complex [K{U(OSi(O Bu))(μ-N)}], The bis-nitride reacts in ambient conditions with 1 equiv. of CS and 1 equiv. of CO resulting in N-C bond formation to afford the diuranium(v) complexes [K{U(OSi(O Bu))(μ-S)(μ-NCS)}], and [K{U(OSi(O Bu))(μ-O)(μ-NCO)}], , respectively. Both nitrides in react with CO resulting in oxidative addition of CO to one nitride and CO cleavage by the second nitride to afford the diuranium(iv) complex [K{U(OSi(O Bu))(μ-O)(μ-NCO)}], . Complex also effects the remarkable oxidative cleavage of H in mild conditions to afford the bis-imido bridged diuranium(iv) complex [K{U(OSi(O Bu))}], that can be further protonated to afford ammonia in 73% yield. Complex provides a good model for hydrogen cleavage by metal nitrides in the Haber-Bosch process. The measured magnetic data show an unusually strong antiferromagnetic coupling between uranium(v) ions in the complexes and with Neel temperatures of 77 K and 60 K respectively, demonstrating that nitrides are attractives linkers for promoting magnetic communication in uranium complexes.
氮化铀配合物因其能够实现二氮还原和官能团化以及促进磁通信而备受关注，但对其性质和反应活性的研究仍然很少。在这里，我们通过氮化物、叠氮桥联的二铀（IV）配合物[K{U(OSi(OtBu))(μ-N)}]的热分解，以73%的产率制备了二铀（V）双氮化物配合物[K{U(OSi(OtBu))}]。双氮化物在环境条件下与1当量的CS和1当量的CO反应，导致N-C键形成，分别得到二铀（V）配合物[K{U(OSi(OtBu))(μ-S)(μ-NCS)}]和[K{U(OSi(OtBu))(μ-O)(μ-NCO)}]。中的两个氮化物都与CO反应，导致CO氧化加成到一个氮化物上，并被第二个氮化物进行CO裂解，得到二铀（IV）配合物[K{U(OSi(OtBu))(μ-O)(μ-NCO)}]。配合物在温和条件下还能实现H的显著氧化裂解，得到双亚氨基桥联的二铀（IV）配合物[K{U(OSi(OtBu))}]，该配合物可进一步质子化，以73%的产率得到氨。配合物为哈伯-博施法中金属氮化物的氢裂解提供了一个很好的模型。测得的磁数据表明，配合物和中铀（V）离子之间存在异常强的反铁磁耦合，奈尔温度分别为77 K和60 K，这表明氮化物是促进铀配合物中磁通信的有吸引力的连接体。
