アルケンの水素化は11頂点のロダチアボランで,クラスタの完全な参加を伴う
Alvaro Alvarez1, Ramón Macías, Jonathan Bould
1Departamento de Química Inorgánica, Instituto Universitario de Catálisis Homogénea, Universidad de Zaragoza-Consejo Superior de Investigaciones Científicas, 50009-Zaragoza, Spain.
Journal of the American Chemical Society
|August 6, 2008
まとめ
この研究は,新しいロジウム-硫黄-ボロンクラスターの合成と反応性を詳細に説明し,提案されたニドからクローソへの変換メカニズムを通じてアルケンの水素化のための触媒的可能性を実証しています.
科学分野:
- 有機金属化学 有機金属化学
- ボロン化学 ボロン化学
- カタリシス カタリシス カタリシス
背景:
- メタルヘテロボランは,独特の構造と反応性プロファイルを持っています.
- nidoからcloso構造への変換を理解することは,触媒的アプリケーションにとって非常に重要です.
- ローダチアボランは,潜在的触媒活動により興味を惹きます.
研究 の 目的:
- 新しい金属ヘテロボラン, [8,8-(PPh 3) 2-ニド-8,7-RhSB 9H 10] (1) を合成し,特徴づけました.
- 化合物1の反応性,特にその変容と触媒的可能性を調査する.
- 合成されたクラスターによって触媒化されたアルケンの水素化のメカニズムを解明する.
主な方法:
- 金属ヘテロボラン [8,8-(PPh 3) 2-ニド-8,7-RhSB 9H 10] (1) の容易な合成
- ピリジン,アルケーン (エーテナ),一酸化炭素との反応.
- スペクトル解析 (NMR) と密度関数理論 (DFT) の計算.
主要な成果:
- nido-hydridorhodathiaborane [8,8,8-(PPh 3) 2H-9-(NC 5H 5) - nido-8,7-RhSB 9H 9] (2) の合成は,1.から開始されている.
- クロソロダチアボラン [1,1-(PPh 3) ((L) -3 ((NC 5H 5) - クロソ-RhSB 9H 8] (3, L=C 2H 4; 4, L=CO) と [1,1-(PPh 3) 2-3- ((NC 5H 5) - クロソ-1,2-RhSB 9H 8] (5) の形成.
- クラスターによって触媒化されたアルケンの水素化と異体化の実証,二重水素移転を含む提案されたnido to closo変換メカニズム.
結論:
- ロジウム・硫黄・ボロン・クラスター・システムは,ニド・トゥ・クローソ変換を含むダイナミックな反応性を示す.
- クラスターは,提案されたメカニズムを通じてアルケンの水素化のための触媒として作用します.
- H 2の活性化メカニズム (単一サイト対クラスター双機能) のさらなる調査は正当化されています.
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