ルテニウム触媒を用いたシス選択的リング開きメタテシスポリメリゼーション.
Benjamin K Keitz1, Alexey Fedorov, Robert H Grubbs
1Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|January 14, 2012
まとめ
ルテニウムベースの触媒は,サイクルアルケンのシス選択的リング開きメタテシスポリメリゼーションを可能にします. ポリマーCis含有量は96%に達し,モノマー構造とポリメリゼーション温度制御で調節できます.
科学分野:
- ポリマー化学のポリマー化学について
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
背景:
- リングオープニングメタテシスポリメリゼーション (ROMP) は,ポリマー合成のための多用途な方法です.
- ROMPにおける高いシス選択性を達成することは,ポリマーの特性を調整するために極めて重要です.
- ルテニウムベースの触媒は,メタテシス反応で調節可能な反応性と選択性を提供します.
研究 の 目的:
- 様々な単環アルケンおよびノルボルネン型モノマーのシス選択環開きメタテシスポリメリゼーションを報告する.
- ポリマー cis 含有量に対するモノマー構造と温度の影響を調査する.
- 制御されたポリメリゼーションのためのC-H活性化ルテニウムベースの触媒の有効性を実証するために.
主な方法:
- C-H活性化,ルテニウムベースのメタテシス触媒を使用した.
- さまざまな単環アルケン,ノルボルネン,およびオックスノルボルネン誘導体でリング開封メタテシスポリメリゼーションを行った.
- ポリマー立体化学への影響を研究するために,ポリマー化温度とモノマー構造の多様化.
主要な成果:
- 研究されたモノメアのシス選択的リング開きメタテシスポリメリゼーションを達成しました.
- 結果となるポリマーのCis含有量は,モノメアの構造と反応温度によって大きく影響されることを実証した.
- ポリメリゼーション条件を最適化し,特に温度を下げることで,高シス含有量である最大96%のポリマーが得られる.
結論:
- 開発されたルテニウムベースの触媒は,シス選択的ROMPを効果的に促進します.
- ROMPにおけるポリマー立体化学は,モノメアの設計と反応温度を調整することによって正確に制御できます.
- ポリメリゼーション温度を下げることは,ROMPにおけるシス選択性を最大化するための重要な戦略です.
関連する概念動画
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