電子が豊富なN-ヘテロサイクリックシリレン (NHSi) -鉄複合体:分離可能なヒドロシリレン-鉄複合体の合成,構造,および触媒能力
Burgert Blom1, Stephan Enthaler, Shigeyoshi Inoue
1Department of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin, Strasse des 17. Juni 135, Sekr. C2, D-10623 Berlin, Germany.
Journal of the American Chemical Society
|April 11, 2013
まとめ
研究者は,最初の電子が豊富なN-ヘテロサイクリックシリレン (NHSi) -鉄0複合体を報告した. 希少なSi(II) 水化物を含むこれらの複合体は,ケトン水酸化で触媒活性を示し,シリコンベースの触媒に対する新しい反応性を示しています.
科学分野:
- 有機金属化学 有機金属化学
- メイングループ 化学
- カタリシス カタリシス カタリシス
背景:
- N-ヘテロサイクリックシリレン (NHSi) は,協調化学における多用途リガンドである.
- 鉄 (((0) 複合体は,触媒的応用のためにユニークな電子特性を提供します.
- Si ((II) 種は一般的に反応性があり,特に移行金属複合体では,分離することが困難です.
研究 の 目的:
- 新しい電子が豊富なN-ヘテロサイクリックシリレン (NHSi) -鉄 (((0) 複合体を合成し,特徴づけること.
- これらのユニークなSi (II) -Fe (0) システムの結合と電子構造を調査する.
- 有機変換におけるSi (II) 水化物複合体の触媒的可能性を調査する.
主な方法:
- Fe(0) 前駆体とN-ヘテロサイクルクロロシリレンとの反応による鉄複合体の合成.
- スペクトロスコーピック法 (NMR,IRなど) を用いた特徴化. そして単結晶X線 difraktion.
- 密度関数理論 (DFT) を用いた計算研究で,結合と反応機構を分析する.
主要な成果:
- 安定したSi(II) 水素複合体を含む最初の電子に富んだNHSi-鉄(0) 複合体の分離と特徴付け.
- DFTの計算では,Si (II) とFe (0) の中心間の多重結合が顕著であることが明らかになっています.
- Si(II) ハイドリド複合体は,ケトンの水溶化において触媒的活性を示し,高い変換率を持つアルコールを生成した.
結論:
- これらの新しいNHSi-鉄複合体の成功した合成と特徴付けは,低値のシリコン化学の範囲を拡大します.
- Si(II) ハイドリド複合体は,水塩化反応の希少かつ貴重な前触媒である.
- この研究は,キーヒドリド転送ステップとシリリウムミリデンの中間物質を含む触媒サイクルに関する機械的洞察を提供します.
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