酸素原子が二酸化炭素からフィッシャーカルベンに (PNP) Irで移転する
Matthew T Whited1, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|April 16, 2008
まとめ
イリジウム複合体は,C-H活性化と酸素原子移転反応を促進する. この研究は,イリジウム (((I) フィッシャーカルベンの複合体の形成と反応性を詳細に説明し,CO2から効率的な原子移転を可能にします.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- C-H アクティベーション
背景:
- ピンサー・リガンドは,触媒的用途における金属複合体の安定化に不可欠である.
- フィッシャーカルベンの複合体は,有機合成における多用途の中間物質である.
- C-H活性化は,有機分子の機能化のための重要な変換である.
研究 の 目的:
- イリジウム (((I) フィッシャーカルベンの複合体の形成と反応性を調査する.
- 原子移転反応におけるこの複合体の触媒的可能性を調査する.
- これらの変換のメカニズムを解明する.
主な方法:
- イリジウムジヒドリド複合体のノルボルニレンによる脱水化.
- 合成したカルベンの複合体が,CO2,カルボニル硫化物,フェニルイソシアネートと反応する.
- CO2の大気下での熱溶解の研究.
- 予備的なメカニズム調査.
主要な成果:
- イリジウム ((I) フィッシャーカルベンの複合体, (PNP) Ir C ((H) OtBuの形成,二重C-H活性化による.
- CO2から量的な酸素原子の移転により,t-ブチルフォーム酸と (PNP) Ir-CO.が生成される.
- カルボニル硫化物とフェニルイソシアネートでそれぞれ硫黄原子とニトロン群の移転が観察されました.
- (PNP) Ir-COとt-ブチルホルマートの形成は,CO2下での熱分解による.
結論:
- 合成されたイリジウムカルベンの複合体は,原子移転反応のための効果的なプラットフォームです.
- 反応は,提案された4つ構成のメタララクトン中間体を通して進みます.
- この研究は,触媒におけるピンチャー結合イリジウム複合体の範囲を拡大する.
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