アルキル群交叉メタテシスによるn-アルキルアレンの触媒合成
Graham E Dobereiner1, Jian Yuan, Richard R Schrock
1Department of Chemistry, 6-331, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|August 6, 2013
まとめ
この研究は,単純なアルカンからn-アルキルアレンを合成するための新しいワンポット方法を導入しています. このプロセスは,イリジウムとボルンガムの触媒を用いて,タンデム反応の高度な選択性と効率性を確保しています.
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
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- 伝統的なn-アルキルアレン合成には,多くの場合,複数のステップと厳しい条件が伴う.
- アルカンの直接機能化のための効率的な触媒システムの開発は,有機合成における重要な課題です.
研究 の 目的:
- アルカンとエチルベンゼンからn-アルキルアレンを直接合成するためのワンポットタンデム反応を開発する.
- この変換のための特定のイリジウム・タングスティン触媒システムの有効性を調査する.
- 高活性で熱的に安定したオレフィンメタテシス触媒の可能性を調査する.
主な方法:
- デヒドロジネーション,オレフィンメタテシス,および水素化を含む1ポットタンデム配列.
- 利用された ((tBu) PCP) IrH2は,トングステンモノアリオロキシドピロリド複合体,特にW ((NAr) ((C3H6) ((pyr) ((OHIPT) (1a) と組み合わせた.
- 複合体1aを用いて様々な条件下でnオクタンの自己メタテシスを研究した.
主要な成果:
- アルカンとエチルベンゼンからn-アルキルアレンを直接合成し,優れた選択性を得ました.
- コンプレックス1aは,n-オクタン自己メタテシスにおいて高い活性を示し,これまでに報告された最も高い製品濃度をもたらしました.
- 触媒の熱安定性により,高温と長い反応時間を用いることができました.
結論:
- 開発されたワンポット・タンデム反応は,n-アルキルアレンへの効率的な経路を提供します.
- イリジウムとボルンガム触媒の相乗効果の組み合わせは,高い選択性と活性を提供します.
- この方法論は,触媒アルカンの機能化とオレフィン転化における重要な進歩を表しています.
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