アルファ-アゴスティックなSi[bond]H相互作用を有するカチオニウムハフニウムシリル複合体によってアレンC[bond]H結合の活性化
1Department of Chemistry, University of California, Berkeley, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|June 13, 2002
まとめ
Zwitterionic ハフニウムシリル複合体は,芳香C-H結合を活性化する. この反応は協調された移行状態を経由して進行し,新たな有機金属反応性およびC-H結合機能化の経路に関する洞察を提供している.
科学分野:
- 有機金属化学 有機金属化学
- シリコン化学 シリコン化学
- C-H アクティベーション
背景:
- ズウィトリアン系有機金属複合体は,ユニークな反応性を持っています.
- ハフニウムシリル複合体は,汎用性の高い合成中間物質である.
- C-H結合の活性化は,有機合成における重要な変換である.
研究 の 目的:
- 新型ズウィテリオン型ハフニウムシリル複合体を合成し,特徴づけること.
- 芳香C−H結合に対するこの複合体の反応性を調査する.
- C-H結合の活性化メカニズムを解明する.
主な方法:
- ズウィトリオニウムハフニウムシリル複合体の合成と特徴付け Cp2Hf(eta2-SiHMes2)(mu-Me) B(C6F5) 3.3.
- アロマティック炭化水素 (ベンゼン,トルーエン) との反応の研究.
- 反応メカニズムを決定するために,運動学的研究と同位体ラベル付けを行います.
主要な成果:
- ズウィテリオン複合体は,異常なアルファ-アゴスティックSi-H相互作用を示しています.
- 複合体はベンゼンとトロウエールと反応し,新しいC-H活性化製品を形成します.
- 運動データと一次運動同位体効果は,協調したC-H活性化メカニズムを支持する.
結論:
- Zwitterionicのハフニウムシリル複合体は,芳香C−H結合を活性化することができる.
- C-Hの活性化は,協調した移行状態を通過します.
- この研究は,オルゴノハフニウム化合物を用いたC-H機能化の新しい方法を提供します.
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