Li Xiao-Wang, Zhang Feng-Xiang, Zhao Xi-Guan, Liu Qing-Yu, He Sheng-Gui, Ma Jia-Bi
Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, China.
State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
J Am Chem Soc. 2025 Jun 25;147(25):22185-22191. doi: 10.1021/jacs.5c06920. Epub 2025 Jun 3.
Transforming N into valuable C-N bond-containing products at room temperature is of great importance, yet it remains highly challenging because of the inherent inertness of N and the complexity in designing effective catalytic active sites. In this study, we investigate the structure and reactivity of InNbC using mass spectrometry, photoelectron spectroscopy, and theoretical calculations. Remarkably, at room temperature, InNbC can completely cleave the N≡N triple bond to form two C-N bonds in the intermediate product Nb(CN), accompanied by the release of the In atom. Subsequently, one cyanide (CN) molecule is liberated during the oxidation reaction of Nb(CN) with O. Comparative analysis with the inert NbC cluster reveals two critical roles of the In atom in the N reduction process: (1) the In atom enhances the negative charge on the Nb site, facilitating N adsorption and reduction. (2) The In atom enables the flexible formation and cleavage of the In-Nb bond during the reaction. In this N transformation, the metal atoms act as electron reservoirs, and the C unit is another important electron donor during C-N bond generation. The formation of strong Nb-O bonds provides the driving force for releasing cyanide as the final product in the subsequent oxidation reaction. This work presents the first gas-phase example of a heteronuclear bimetallic anion, InNbC, capable of releasing cyanide as a product under thermochemical conditions. Our findings propose a novel strategy for designing N transformation catalysts by integrating p-block main group metals with d-block transition metals, offering new insights into the activation and functionalization of N.
在室温下将氮转化为含碳氮键的有价值产物具有重要意义，但由于氮的固有惰性以及设计有效催化活性位点的复杂性，这仍然极具挑战性。在本研究中，我们使用质谱、光电子能谱和理论计算来研究铟铌碳化物（InNbC）的结构和反应活性。值得注意的是，在室温下，InNbC能够完全裂解氮氮三键，在中间产物铌氰化物（Nb(CN)）中形成两个碳氮键，同时释放出铟原子。随后，在Nb(CN)与氧气的氧化反应过程中会释放出一个氰化物（CN）分子。与惰性的NbC簇进行对比分析，揭示了铟原子在氮还原过程中的两个关键作用：（1）铟原子增强了铌位点上的负电荷，促进了氮的吸附和还原。（2）铟原子使得在反应过程中能够灵活地形成和裂解铟 - 铌键。在这种氮转化过程中，金属原子充当电子库，而碳单元是碳氮键形成过程中的另一个重要电子供体。强铌 - 氧键的形成提供了驱动力，使得氰化物在随后的氧化反应中作为最终产物释放出来。这项工作展示了第一个异核双金属阴离子InNbC在热化学条件下能够作为产物释放氰化物的气相实例。我们的研究结果提出了一种通过将p区主族金属与d区过渡金属相结合来设计氮转化催化剂的新策略，为氮的活化和功能化提供了新的见解。
