L-ラクチドと ε-カプロラクトンに対するグループ4の金属環開きポリメリゼーション活性に対するレドックス制御
Xinke Wang1, Arnaud Thevenon, Jonathan L Brosmer
1Department of Chemistry and Biochemistry, University of California, Los Angeles , 607 Charles E. Young Drive East, Los Angeles, California 90095, United States.
Journal of the American Chemical Society
|July 26, 2014
まとめ
フェロセネリガンドを用いた金属複合体のレドックス制御は,ラクチドとカプロラクトンのポリメリゼーション率を調節した. このスイッチング行動は,単一の反応容器でブロックコポリマーの合成を可能にしました.
科学分野:
- オーガノメタリック化学
- ポリマー科学は,ポリマー科学である.
背景:
- フェロゼンベースのリガンドは,触媒設計にユニークな酸化還元特性を提供します.
- 環開きポリメリゼーションは,ポリラクチドやポリキャプロラクトンなどの生物分解性ポリマーを生産するための重要な方法です.
研究 の 目的:
- グループ4の金属アルコキシド複合体の活性に対する酸化還元状態の影響を調査する.
- レドックス反応剤を用いて,乳化物とカプロラクトンのリング開きポリメリゼーションを制御する.
- ブロックコポリマーのワンポット合成を達成するために.
主な方法:
- フェロゼン基リガンドでサポートされるグループ4の金属アルコシド複合体の合成.
- l-ラクチドとe-カプロラクトンのリング開きポリメリゼーション.
- リドックス反応剤を用いた金属複合体のインシットリドックススイッチング.
- その結果生成されるポリマーおよび共ポリマーの特性.
主要な成果:
- ポリメリゼーション速度は,金属複合体の酸化還元状態を切り替えることで調節された.
- リドックス状態がポリメリゼーション速度に及ぼす反対の効果は,l-ラクチドとe-カプロラクトンで観察されました.
- l-ラクチドとe-カプロラクトンからブロックコポリマーを1つのポットで成功裏に合成することが示されました.
結論:
- フェロゼン基リガンドの還酸化活性が,ポリメリゼーション運動を制御するために効果的に利用できます.
- この再酸化交換可能な触媒は,特異な性質を持つブロックコポリマーを合成するための新しいアプローチを提供します.
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