サイクロプロペンのパラジウム触媒生/制御ビニル添加ポリメリゼーション
Zepeng Zhang1,2, Yunpeng Gao1, Shufeng Chen2
1Beijing National Laboratory of Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
Journal of the American Chemical Society
|October 14, 2021
まとめ
この研究では,パラジウム触媒を用いたサイクロプロペン (CPE) の生体ビニル添加ポリメリゼーションが実証されました. この突破は以前の課題を克服し 新しいポリマーの制御された合成を可能にします
科学分野:
- ポリマー化学
- 有機合成
- カタリシス
背景:
- サイクロプロペンは,有機合成およびリング開きメタテシスポリメリゼーション (ROMP) で多用途な構成要素である.
- CPEsのビニル添加ポリメリゼーションは十分に研究されていないが,中間の不安定性と増殖障壁のために生きた/制御されたポリメリゼーションは重要な課題である.
研究 の 目的:
- 3-メチル-3-カルボキシメチルサイクロプロペン (CPE) の生/制御されたビニル添加ポリメリゼーションを達成するために.
- 制御されたポリメリゼーションを可能にする触媒システムとメカニズムを調査する.
主な方法:
- パラジウム触媒,特に [Pd(π-アリル) Cl]2を使用し,スルフィナミドビスホスフィンリガンドと調整した.
- 3-メチル-3-カルボキシメチルCPEのポリメリゼーションを行った.
- 分析されたポリメリゼーション運動,分子量 (Mn),分子量分散 (Mw/Mn).
- 連続的なモノマー添加による制御されたブロック共ポリメリゼーションを実行した.
主要な成果:
- 数値平均分子量 (Mn) とモノマー変換の間の線形関係を示した.
- ポリメリゼーションを通じて狭い分子量分散 (Mw/Mn) を維持した.
- モノマーと触媒の比率で線形的に増加した.
- 制御されたブロック共ポリメリゼーションを成功裏に達成し,ポリメリゼーションの生きた性質を確認しました.
結論:
- 開発されたパラジウム触媒システムは,特定のサイクロプロペンの生体/制御されたビニル添加ポリメリゼーションを可能にします.
- 触媒リガンドとサイクロプロペンのカルボニル群の間の相乗効果は,制御されたポリメリゼーションを達成するために不可欠です.
- この方法は,よく定義されたサイクロプロペンベースのポリマーを合成するための新しい道を開きます.
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