金属-炭素結合に酸素原子を挿入するための可変経路:Cp*W(O) 2(CH2SiMe3) のケース
Jiajun Mei1, Kurtis M Carsch, Cody R Freitag
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, United States.
Journal of the American Chemical Society
|December 25, 2012
まとめ
オーガノメタリック複合体Cp*W(O)(2)(CH(2)SiMe(3)) は,酸素ドナーと反応してトリメチルシリルメタノールを形成する. ペリオデートと過酸化水素で異なる反応経路が観察され,リガンドの移動とプロトノリシスを含む.
科学分野:
- 有機金属化学 有機金属化学
- トングステンの化学
- 酸化反応は,酸化反応によるものです.
背景:
- Cp*W ((O) ((2) ((CH ((2) SiMe ((3)) は,よく定義された有機金属複合体である.
- 酸素ドナーと金属アルキル結合の反応性を理解することは,触媒と合成において極めて重要です.
- 以前の研究では,関連するボルンガム複合体を調査しましたが,さまざまな酸素原子ドナーを持つ特定のメカニズムについては,さらなる解明が必要です.
研究 の 目的:
- 様々な酸素原子ドナー,特にペリオデートと過酸化水素との反応経路を調査するために,Cp * W ((O) ((2) ((CH ((2) SiMe ((3)) の反応経路を調査します.
- トリメチルシリルメタノール形成のメカニズム的な詳細を解明する.
- 異なる酸素源で反応性とメカニズムの結果を比較する.
主な方法:
- Cp*W ((O) ((2) ((CH ((2))) SiMe ((3))) とIO ((4) ((-) とH ((2) O ((2)) がTHF/水で反応する.
- 反応中介物質と反応製品の特性.
- 酸塩触媒を用いたメカニズム研究.
主要な成果:
- IO (((4) ((-) との反応により,IO (((3) ((-)) の調整,リガンド移動,解離を経由してTMSCH (((2) OHが得られます.
- H(2) O(2) と反応すると,エタ(2) -ペロキソ複合体,Cp*W(O) 及びエタ(2) -O(2)) 及びCH(2) 及びSiMe(3) を形成する.
- 酸性または塩基性触媒は,リガンドの移動と陽子分解を含む異なるメカニズム的経路を通って,エタ2ペロキソ複合体をTMSCH2OHに変換します.
結論:
- 酸素原子ドナーとCp*W ((O)) ((2) ((CH ((2) SiMe ((3)) の反応は,異なる経路を通ってトリメチルシリルメタノールの形成につながります.
- 酸素ドナーの性質が初期反応経路を決定し,直接のリガンド移動かペロキソ中間物質の形成である.
- 酸と塩基の両方の触媒は,リガンドの移行を通じて,ペロキソ中間物の最終アルコール製品への変換を容易にすることができます.
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