Ni ((II) - 触媒による非交代性エチレン-一酸化炭素共ポリマー化のメカニズムに関する洞察
Maria Voccia1, Lukas Odenwald2, Maximilian Baur2
1Department of Chemistry, University of Salerno, Via Giovanni Paolo II, 84084 Fisciano, Salerno, Italy.
Journal of the American Chemical Society
|August 9, 2022
まとめ
研究者はエチレンと一酸化炭素を使って ケト群でポリエチレンを作る方法を発見しました この非交代性共ポリメリゼーションの突破は 新しい機能的材料の開発の鍵となるものです
科学分野:
- ポリマー化学
- 有機金属化学
- カタリシス
背景:
- エチレンと一酸化炭素の非交代共聚化により,ケト基を持つポリエチレンが得られる.
- ニッケル (II) フォスフィンフェノラート触媒は,この反応を可能にします.
- 反応メカニズムの理解は,触媒の設計に不可欠です.
研究 の 目的:
- エチレンと一酸化炭素の非交代共聚化のメカニズムを解明する.
- 交代経路と非交代経路の両方の速度決定ステップを特定する.
- コポリマーマイクロ構造の制御における触媒構造の役割を理解する.
主な方法:
- 触媒活性種の密度関数理論 (DFT) 計算
- 圧力反応器共聚合によるポリマー微細構造の実験分析.
- 様々なNi (II) フォスフィンフェノラート触媒の調査
主要な成果:
- 非交代結合の速度を決定するステップは,アルキル-オレフィン中間物のシス/トランスイソメリゼーションである.
- C,O-ケラートを開くためのエチレン結合は,交代モチーフ形成の決定的なステップです.
- 特定のNi ((II) 触媒特性であるP結合の芳香分子の η2調整は,経路の競争に影響する.
結論:
- このメカニズムは,電子とステリック要素の微妙なバランスを伴う.
- 触媒の設計,特にリガンドの形状的制約は,非交代共聚化への選択性を調整することができます.
- この研究は,機能的なポリオレフィンのための触媒の設計のための基本的な洞察を提供します.
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