エタ9,エタ5-ビス(インデニル) ジルコニウムサンドイッチ複合体による炭素-酸素結合割れ
Christopher A Bradley1, Luis F Veiros, Doris Pun
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA.
Journal of the American Chemical Society
|December 21, 2006
まとめ
ビス・インデニル・ジルコニウム複合体は,ダイアルキルエーテル内のC−O結合を素早く割ってアルコキシヒドリド複合体を形成する. この反応メカニズムは,速度を決定するC-H活性化と,その後のβ-アルコキシドの除去を含む.
科学分野:
- 有機金属化学 有機金属化学
- ジルコニア化学 ジルコニア化学
- カタリシス カタリシス カタリシス
背景:
- ビス・インデニル・ジルコニウム複合体は,多用途の有機金属化合物である.
- エーテルとの反応性を理解することは,合成アプリケーションにとって極めて重要です.
研究 の 目的:
- ダイアルキルエーテルとビス・インデニル・ジルコニウム複合体の反応機構を調査する.
- アルコキシヒドリド複合体と自由オレフィン形成の解明.
主な方法:
- 様々なダイアルキルエーテルを用いたeta9,eta5-bis(インデニル) ジルコニウム複合体の処理.
- 運動同位体効果の研究と速度分析.
- eta6,eta5-bis(indenyl) zirconiumのTHF化合物の熱分解について.
- 機械学と計算学の研究.
主要な成果:
- 容易なC-O結合分裂が発生し,eta5,eta5-bis(インデニル) ジルコニウムアルコキシヒドリド複合体とオレフィンが生じた.
- エチレンが形成されたときに,希少な,結晶学的に特徴づけられた,塩基のないeta5,eta5-bis(indenyl) zirconiumエチレン複合体が分離されました.
- 証拠は,速度を決定するC-H活性化に続いてβ-アルコキシドの除去を含むメカニズムを支持しています.
- また,eta6,eta5-bis(indenyl) zirconiumのTHF化合物の熱分解により,C-O結合が分裂した.
結論:
- 反応は,ハプトトロピク再配置,C-H活性化,C-O結合分裂を含むメカニズムを通じて進行する.
- この研究は,有機金属合成と触媒に関連する,エーテル付きのビス・インデニル・ジルコニウム複合体の反応性に関する洞察を提供します.
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