ウラン触媒が空気中の窒素をアンモニアへ変換（Uranium-Based Catalyst Turns Air Nitrogen into Ammonia）

2025-07-21 スイス連邦工科大学ローザンヌ校（EPFL）

＜関連情報＞

• https://actu.epfl.ch/news/uranium-based-catalyst-turns-air-nitrogen-into-amm/
• https://www.nature.com/articles/s41557-025-01867-z

ウラン錯体を介したサイドオン結合二窒素のアンモニアへの触媒的・化学量論的段階的変換 Catalytic and stoichiometric stepwise conversion of side-on bound dinitrogen to ammonia mediated by a uranium complex

Mikhail S. Batov,Heather T. Partlow,Lucile Chatelain,John A. Seed,Rosario Scopelliti,Ivica Zivkovic,Ralph W. Adams,Stephen T. Liddle & Marinella Mazzanti
Nature Chemistry  Published:16 July 2025
DOI:https://doi.org/10.1038/s41557-025-01867-z

Abstract

The well-defined catalytic conversion of dinitrogen (N₂) to ammonia (NH₃) by molecular complexes is of fundamental interest and important for providing an atomic-level understanding of reactivity that can be related to industrial and biological nitrogen-fixation processes. Molecular catalytic N₂ to NH₃ conversion currently involves the reduction and protonation of terminal or bridging end-on bound metal–N₂ complexes. However, catalytic N₂ to NH₃ conversion by side-on bound metal–N₂ molecular complexes is relevant to both the industrial and biological nitrogen-fixation processes. Here, using a uranium triamidoamine complex, we report catalytic N₂ to NH₃ conversion involving side-on bound N₂ binding. Stoichiometric reactions reveal stepwise reduction of N₂ from free N₂ to bridging side-on bound forms and subsequently to bridging nitrides, uniquely accessing four different states of side-on bound N₂ for the same molecular system. This reveals the roles of N₂, N₂²⁻, N₂³⁻, N₂⁴⁻ and N³⁻ in the catalytic conversion of N₂ to NH₃ when involving side-on bridging N₂.