エチレンオリゴメリゼーションとポリメリゼーションのための新しいクロム触媒の発見と最適化,高通量スクリーニングによる支援
David J Jones1, Vernon C Gibson, Simon M Green
1Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom.
Journal of the American Chemical Society
|August 4, 2005
まとめ
新しいクロム触媒は,エチレンを効率的にオリゴメリ化し,ポリメリ化する. ハイ・スループット・スクリーニングにより,新型のシフ基リンガンドが特定され,オレフィン変換のための高度に活性なシステムにつながった.
科学分野:
- 有機金属化学 有機金属化学
- ポリマーサイエンスの科学
- カタリシス カタリシス カタリシス
背景:
- シーフ基底リガンドは,協調化学において多用途である.
- クロミウムベースの触媒は,オレフィンポリメリゼーションに不可欠です.
- エチレンオリゴメリゼーションとポリメリゼーションのための効率的な触媒の開発は,依然として重要な課題です.
研究 の 目的:
- エチレンオリゴメリゼーションとポリメリゼーションのための新しい,高度に活性なクロム基触媒を発見する.
- 大量のオーソシブシチュエントを持つシフ塩基リガンドの構造-活性関係を探求する.
主な方法:
- シーフ塩基サリシルアルディミンリガンドライブラリ205個のHTSスクリーニング.
- (p-tolyl) CrCl2 ((thf) 3.3) とのリガンドのインシット反応
- X線結晶学を用いた触媒前駆体の特徴化.
主要な成果:
- 高活性なクロムベースのシステムの2つの新しいクラスを特定しました.
- ポリメリゼーション系:ビデント酸アンスラセニルシフ基で,最大3000g×mmol{-1) h{-1) bar{-1) }を産出する.
- オリゴメリゼーション触媒:トリデント酸トリプチセニルシフ基は,最大1万g×mmol{-1}h{-1}bar{-1}) を生成する.
結論:
- 大量のオーソ置換されたシーフ基底リガンドは,エチレン変換のための高度に活性なクロム触媒を可能にします.
- リンガンド構造は,オリゴメリゼーションまたはポリメリゼーションのいずれかの触媒活動を決定する.
- X線結晶学により,主要な触媒前駆体構造が確認されました.
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