同質のエチレンオリゴメリゼーション触媒から生じた前例のないアルファオレフィン分布
Atanas K Tomov1, Juan J Chirinos, Richard J Long
1Imperial College London, South Kensington Campus, London SW7 2AY, UK.
Journal of the American Chemical Society
|June 15, 2006
まとめ
新型クロム触媒がエチレンを効率的にオリゴメリゼートし,アルファオレフィンのユニークな分布を生成します. この異常な製品選択性は,二重触媒部位を含む金属環鎖成長機構によって説明される.
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:
- クロミウム複合体は,オレフィン・オリゴメリゼーションの触媒として知られています.
- オレフィンオリゴメリゼーションにおける製品配分の制御は,依然として重要な課題です.
研究 の 目的:
- ビス・ベンジミダゾリル・アミン・クロミウム複合体の触媒活性と製品選択性を調査する.
- 観察された異常な製品分布の背後にあるメカニズムを解明する.
主な方法:
- クロミウム複合体とメチルアルミノキサン (MAO) を使用したエチレンオリゴメリゼーション.
- 反応経路を調査するためのデウテリウムラベリングの研究.
- 1-オレフィン製品の分布の分析.
主要な成果:
- 触媒は,エチレンオリゴメリゼーションに対して非常に高い活性を示した.
- 前例のない製品分布が観察され,C4nシリーズのオレフィンがC4n+2シリーズのオレフィンよりも著しく豊富であった.
- デュテリウムのラベル付けは,金属環鎖の成長メカニズムを支えた.
結論:
- ビス (((ベンジミダゾリル) アミンクロム複合体は,高度に活性で選択的なオリゴメリゼーション触媒である.
- 異常な製品分布は,金属循環機構内の2つの異なる触媒部位の相互作用から生じる.
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