環開きメタテシスポリメリゼーションにおけるステレオセレクティビティをサイクロメタル化ルテニウム基触媒によって探求する:実験と計算による研究
L E Rosebrugh1, T S Ahmed1, V M Marx1
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.
Journal of the American Chemical Society
|January 5, 2016
まとめ
ルテニウム触媒を用いたリング開封メタテシスポリメリゼーション (ROMP) は,シス,シンディオタクティックな微細構造を持つポリマーを生成する. ポリマーの構造の誤差は,金属制御とイソメリゼーションメカニズムによって説明されます.
科学分野:
- ポリマー化学
- 有機金属化学
- 材料科学
背景:
- リング開封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ある.
- ポリマーの微細構造の制御は 材料の特性を調整するために不可欠です
- サイクロメタル化ルテニウムカルベンの触媒は,ROMPでユニークな反応性を提供します.
研究 の 目的:
- ROMPで合成されたポリマーの微細構造特性を調査する.
- 特定のルテニウム触媒でROMPを制御するステレオ化学的制御メカニズムを解明する.
- ROMPポリマーの微細構造の欠陥の起源を理解する.
主な方法:
- ポリマーマイクロ構造の実験調査
- 反応中介物や移行構造を含む計算方法による分析.
- 実験結果と理論的予測の相関関係
主要な成果:
- 生成されたポリマーは,シス,シンディオタクティックな微細構造を強く好みます.
- ポリマー鎖では最小の頭から尾のバイアスが観察されました.
- トランスエラーがある場合も,シンディオタクティックであることが判明しました.
- 計算分析は,シス・シンディオ・セレクティビティのためのステレオジェニック・メタル制御を含むメカニズムを支持した.
結論:
- この研究は,サイクロメタラートルセニウム触媒を用いたROMPのステレオ選択的メカニズムを明らかにしている.
- ステレオメタルの制御は シス・シンディオタクシーの好みを決定する
- RuC二重結合の周りの回転によるアルキリデンの異体化が,マイクロ構造上のエラーの主要な原因である.
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