メタル/リガンド・プロトン・タウトメリスムは二核 H2の還元性除去を促進する
Jonathan L Kuo1, Karen I Goldberg1
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|December 10, 2020
まとめ
この研究では,外部のリガンドによって制御可能な金属/リガンド陽子のタウトメリズムを示すイリジウム水化物複合体を合成した. この均衡は水素ガスの生成を容易にし,陽子反応触媒の設計のための新しい戦略を提供します.
科学分野:
- 有機金属化学
- カタリシス
- 協調化学
背景:
- 金属複合体におけるプロトンのタウトメリスムは,触媒的活動に不可欠である.
- メタル-リガンドのプロトネーション均衡を制御することは,反応性のある触媒の設計の鍵です.
研究 の 目的:
- 新しい八面体 Ir (III) - 水素複合体を合成し,特徴づけること.
- 金属/リガンドのプロトンのタウトメリズムと,外因的リガンドによる制御を調査する.
- イリジウムヒドリド複合体から H2 の生成のメカニズムを解明する.
主な方法:
- Ir (III) -ヒドリド複合体 ([1-MH]+) をIr (I) 前駆体から合成する.
- メタルヒドリドとリガンドのプロトン化種間の均衡を研究する紫外線スペクトロスコーピー.
- H2生成とIr (II) ダイマー形成の経路を決定するためのメカニズム研究.
主要な成果:
- [HIr-κ3-NNH-NN-CO-tBuPy]+ ([1-MH]+) のイールヒドリド複合体の合成に成功した.
- [1-MH]+と正方形の平面のIr(I) 種 ([2-LH]+) の間の[tBuPy]依存の均衡の観測.
- [1-MH]+の2eqivが軽度な条件下でH2を放出し,Ir(II) ダイマー ([7]2+) を形成することを示す.
結論:
- 金属/リガンドプロトンタウトメリスムは,外因的リガンド濃度によって制御可能である.
- このタウトメリゼーションは,リガンド解離のための低エネルギー経路を提供し,H2の生成を可能にします.
- この発見は,制御されたタウトメリズムに基づくプロトン反応性触媒の設計のための新しい戦略を導入する.
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