二重アンサ-ジルコノセネス:プロピレンポリメリゼーションのためのステレオ選択的合成と高い活性
Eugene Y-X Chen1, Richard E Campbell, David D Devore
1The Dow Chemical Company, Midland, Michigan 48674, USA. eychen@lamar.colostate.edu
Journal of the American Chemical Society
|January 8, 2004
まとめ
研究者らは新種のジルコニウム (II) ダイエンの複合体と高度に活性なアンサ-ジルコノセンの触媒を合成した. これらの発見は,有機金属化学とオレフィンポリメリゼーション触媒を前進させる.
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
背景:
- ジルコニウム複合体は,触媒作用において極めて重要です.
- 低値ジルコニウム化合物の効率的な合成経路の開発は,継続的な課題です.
研究 の 目的:
- 新種のジルコニウム (II) ディエンの複合体を合成する.
- 非常に活性な同型プロピレンポリメリゼーション触媒を開発する.
主な方法:
- トランス-1,4-ディフェニル-1,3-ブタジエンの存在において,リチウム粉でZrCl4(PR3) 2を還元する.
- その結果生じるジルコニウム (((II) ディエンの複合体がLi2{Me2Si(2-Me-4-Ph-Ind) 2}と反応する.
主要な成果:
- ジルコニウム (II) ディエネ複合体 (1) の高収量 (90-93%) が達成されました.
- ラセミックである二価アンサ-ジルコノセンの定量生産が達成された (3).
- アンサ-ジルコノセーン (3) は,活性化時に同型プロピレンポリメリゼーションにおいて高い活性を示した.
結論:
- 低値ジルコニウムダイエンの複合体への新しい合成経路が確立されました.
- 合成されたアンサ-ジルコノセンは,同型プロピレンポリメリゼーションの強力な触媒である.
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