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Updated: Jun 29, 2025

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異質ロジウム単原子位触媒は,化学選択カルベンのN-H結合の挿入を可能にします

Yuanjun Chen^1,2, Ruixue Zhang¹, Zhiwen Chen³

¹Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Frontiers Science Center for Materiobiology and Dynamic Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.

Journal of the American Chemical Society

|April 7, 2024

まとめ

新しいロジウム単原子サイト触媒は,選択的な窒素-水素結合カルベンの挿入反応を可能にします. この異質な触媒は,同質な触媒で見られる化学選択性の課題を克服し,C-N結合形成のための強力な新しいツールを提供します.

科学分野:

有機化学
カタリシス
材料科学

背景:

移行金属で触媒化されたカルベンのN−H結合への挿入は,C−N結合の形成に不可欠である.
均質な触媒は,高度に電愛性のある金属カルベンの中間物質により,化学選択性の課題に直面しています.
有機合成の効率化には選択的な異質な触媒の開発が不可欠です

研究の目的:

移行金属で触媒化されたカルベンの挿入反応のための高度に選択的な異質な触媒を開発する.
既存の均質な触媒の化学選択性の限界に対処する.
有機合成における単原子部位触媒の可能性を探求する.

主な方法:

炭素基にN原子とP原子をドーピングしたロジウム単原子サイト (Rh-SA) 触媒の合成.
アニリン,ヘテロアリルアミン,ディアゾエステルとのカルベンの挿入反応におけるRh-SA触媒の性能を試験する.
密度関数理論 (DFT) の計算を用いて,触媒機構と選択性を解明する.

主要な成果:

Rh-SA触媒は低触媒負荷 (0.15 mol %) で優れた性能を示した.
副産物を生成する同質な触媒とは異なり,複数の核愛性サイトを持つアニリン誘導体への選択的N-H挿入が達成されました.
様々なダイアゾエステルにおいて一貫した選択性が観察され,広範な適用性を示した.

結論:

単原子位触媒は,異質なカルベンの挿入反応に対して強力で選択的なアプローチを提供します.
Rh-SA触媒は,同質な対称性と比較して優れた化学選択性を提供します.
触媒の支柱に含まれるリン原子は,加速された陽子移転によって選択性を高める上で重要な役割を果たします.

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