アンサ-ジルコノセンのエステルエノラート:合成,構造,オーガノ-ルイス酸との反応,およびメタクリラートのポリメリゼーションへの応用
Andrew D Bolig1, Eugene Y-X Chen
1Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872, USA.
Journal of the American Chemical Society
|April 15, 2004
まとめ
この研究では,メタクリラートの高同特異性ポリメリゼーションのための新しいアンサ-ジルコノセンエステルエノラート複合体を報告しています. これらの触媒は,狭い分子量分布と高い戦術性を持つポリマーを生成します.
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:
- アンサ-ジルコノセーン複合体は,オレフィンポリメリゼーションにおいて極めて重要です.
- エステルエノラート複合体は,制御されたポリメリゼーションのためのユニークな反応性を提供します.
研究 の 目的:
- 新しいアンサ-ジルコノセーンエステルエノラート複合体を合成し,特徴づけること.
- メタクリラートの同型ポリメリゼーションにおけるその応用を調査する.
主な方法:
- モノ・デイスター・エノラート複合物の合成.
- X線微分法を用いた構造的特徴化.
- メチルメタクリlate (MMA) とn-ブチルメタクリlate (BMA) とのポリメリゼーション研究.
主要な成果:
- アンサ-ジルコノセンの単体およびダイステルエノラート複合体の最初の例が合成されました.
- カチオン複合体3とインシット生成複合体1は,MMAとBMAのポリメリゼーションに対して高い活性と同特異性を示しています.
- 非常に狭い分子量分布 (M (w) /M (n) =1.03) が達成されました.
- アルミネート複合体4は,連鎖末端制御を通じてシンディオタキシカルPMMAを生成する.
結論:
- アンサ-ジルコノセーンエステルエノラートは,同同型メタクリlateポリメリゼーションの効果的な触媒である.
- 触媒の構造がステレオ選択性を決定する (異種対シンディオタクシー).
- エナチオモルフィックサイト制御は,狭いMWDを持つ高同位性ポリマーにつながります.
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