アミン触媒溶媒によるC-H結合の活性化が,カチオンのデカメチルジルコノセン・オレフィンポリメリゼーション触媒の無活性化経路として用いられる
Itzel Guerrero Rios1, Elena Novarino, Siebe van der Veer
1Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Journal of the American Chemical Society
|November 6, 2009
まとめ
三次アミンはシグマ結合メタテシス経由でブロモベンゼン-d(5) のC-D活性化を加速する. これは,最初のデプロトネーションと,試験キラムモニウムカチオンとの後の反応を伴うもので,シグマ-アリル複合体を形成します.
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
背景:
- デカメチルジルコノコーセンの複合体は活性触媒である.
- C-HとC-Dの活性化は,有機金属化学における基本的な反応である.
研究 の 目的:
- デカメチルジルコノセンのメチルカチオンによって触媒化されたブロモベンゼン-d ((5) のC-D活性化における三次アミンの役割を調査する.
- 加速シグマ結合メタテシス反応のメカニズムを解明する.
主な方法:
- ブロモベンゼン-d(5) とデカメチルジルコノセンのメチルカチオン前駆体を用いたC-D活性化の実験研究.
- 反応機構を調査するための計算研究 (DFT).
主要な成果:
- 三次アミンは,ブロモベンゼン-dのC-D活性化を著しく加速する.
- 計算による研究は,金属の協調球内のアミンによる初期デプロトン化を伴うメカニズムを示しています.
- この反応はシグマ結合の転移を経て,シグマ-アリル複合体を形成する.
結論:
- 三次アミンは,デカメチルジルコノセンの複合体によるブロモベンゼン-d ((5) のシグマ結合転移の触媒または促進剤として作用する.
- 提案されたメカニズムは,アミン加速度C-H/C-D活性化反応の洞察を提供します.
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