Nature Catalysis ( IF 42.8 ) Pub Date : 2023-09-21 , DOI: 10.1038/s41929-023-01025-z Guo Chen , Piao He , Chao Liu , Xiu-Fang Mo , Jing-Jing Wei , Ze-Wen Chen , Tao Cheng , Li-Zhi Fu , Xiao-Yi Yi
A century after hydrazine was discovered, its synthesis remains a challenge due to its high energy requirement and favourable subsequent conversion. As an alternative to the traditional industrial processes, the direct electrochemical oxidation of ammonia is an ideal reaction for hydrazine synthesis. However, suitable methods still need to be developed. Here we show that ruthenium complexes bearing 2-[5-(pyridin-2-yl)-1H-pyrrol-2-yl]pyridine ligands display high catalytic activity for the direct electrochemical oxidation of ammonia to generate hydrazine in acetonitrile. Our developed CSU-2 complex reached a turnover number for hydrazine formation of 5,735 within 24 h at an applied potential of 1.0 V versus Cp2Fe+/0. The results reveal a bimolecular N‒N coupling mechanism involving RuII–aminyl or RuIII–iminyl intermediates.
中文翻译:
高效电化学钌催化氨氧化直接合成肼
肼被发现一个世纪后,由于其高能量需求和有利的后续转化,其合成仍然是一个挑战。作为传统工业过程的替代,氨的直接电化学氧化是合成肼的理想反应。然而,仍然需要开发合适的方法。在这里,我们发现带有2-[5-(吡啶-2-基)-1 H-吡咯-2-基]吡啶配体的钌配合物对于氨在乙腈中直接电化学氧化生成肼表现出高催化活性。我们开发的 CSU-2 复合物在 1.0 V 的外加电位(相对于 Cp 2 Fe +/0)下,24 小时内形成肼的周转数达到 5,735。结果揭示了涉及 Ru II - 氨基或 Ru III - 亚氨基中间体的双分子 N-N 偶联机制。