ベータ-ディケチミナト ("ナックナック") リガンドのフレームワークで支えられているカチオン性スカンジウムメチル複合体
Paul G Hayes1, Warren E Piers, Robert McDonald
1Department of Chemistry, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, Canada.
Journal of the American Chemical Society
|March 7, 2002
まとめ
新しいスカンジウム複合体は,エチレンポリメリゼーションのための非常に活性なスカンジウムアルキルカチオンを形成します. ボランによって活性化されるこれらの触媒は,グループ4のメタロケネ系と比較できる性能を示しています.
科学分野:
- 有機金属化学 有機金属化学
- ポリメリゼーション触媒
- スカンジウム複合体
背景:
- 大容量のベータ・ディケチミナート・リガンドは,塩基のない金属複合体を安定させる.
- B ((C ((6) F ((5)) ((3))) のような有機金属ルイス酸は,金属前駆体活性化に不可欠です.
研究 の 目的:
- ディメチルスカンジウム複合体からスカンジウムアルキルカチオンを合成し,特徴づけること.
- エチレンポリメリゼーションにおけるこれらのスカンジウム複合体の触媒活性を調べる.
主な方法:
- ディメチル・スカンジウム複合体のB (C) (6) F (5)) (3) との反応
- 顕微鏡特性分析 (NMR) とX線結晶学.
- エチレンポリメリゼーション実験.
主要な成果:
- モノケチオン型ミュメチルダイマーとモノメリック型メチルカチオンの形成.
- 独特のディケーション性スカンジウム種の特徴.
- エチレンポリメリゼーションの高触媒活性で,グループ4の金属塩基系に接近しています.
結論:
- 塩基のないジメチル・スカンジウム複合体は,触媒的に活性なスカンジウムカチオンの効果的な前駆体として機能する.
- 観察された触媒活性は,オレフィンポリメリゼーションにおけるグループ3の金属の潜在能力を強調しています.
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