イリジウムから1-メチルニコチナミドへの光学的に交換可能な水素の移転は,熱化学的サイクルによって合理化されます
Seth M Barrett1, Catherine L Pitman, Andrew G Walden
1Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
Journal of the American Chemical Society
|October 10, 2014
まとめ
可視光は強力なイリジウム複合体を活性化し,水素を輸送し,そのドナー能力を高めます. この光誘発反応により,有機分子の制御された減少とH2の放出が可能になります.
科学分野:
- 有機金属化学 有機金属化学
- フォトケミストリー フォトケミストリー
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- イリジウム複合体は,汎用的な触媒である.
- 水素の移転は,有機反応において極めて重要です.
- 可視光光化学は,持続可能な合成ルートを提供しています.
研究 の 目的:
- イリジウム複合体からの可視光誘発ヒドリド移転を調査する.
- 興奮状態のヒドリドドナー能力 (水分性) を定量化するために.
- 有機基質の光交換可能な還元を調査する.
主な方法:
- イリジウム複合体の合成と特徴付け [Cp*Ir(bpy) ((H) ] ((+)).
- 興奮状態の水分性を予測するために新しい熱化学サイクルを利用した.
- 有機酸と1-メチルニコチナミド (MNA(+)) との光化学実験を行った.
主要な成果:
- 有機酸の存在下で,イリジウム複合体から光触発されたH2の放出が観察されました.
- 興奮状態で水分性の有意な増加 (≥18 kcal/mol) を示した.
- 展示されたフォトスイッチング可能なヒドリドがMNA (((+) に転送され,製品形成を制御する.
結論:
- イリジウム複合体は,可視光の下では強力な光水化物として作用する.
- 興奮状態の水分性は著しく強化され,新しい反応性を可能にすることができます.
- 可視光は,水素移転反応と製品選択性を正確に制御します.
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