ルテニウムメタテシス触媒を用いたリング開きメタテシスポリメリゼーションによる高度にシス,シンディオタクティックなポリマーの合成
Lauren E Rosebrugh1, Vanessa M Marx, Benjamin K Keitz
1Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|June 21, 2013
まとめ
ルテニウム触媒は,リング開きメタテシスポリメリゼーションを可能にし,高度にシスおよび戦術性ポリマーを作成します. このブレークスルーにより,ポリマーの微細構造を正確に制御でき,多くの場合95%以上のCIS含有量と戦術性を達成できます.
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
- マテリアルサイエンス 材料科学
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強力な技術です.
- ROMPで同時に高い cis 選択性と戦術性を達成することは,大きな課題でした.
- ルテニウム触媒は,様々なポリメリゼーション反応において有望であることが示されています.
研究 の 目的:
- ルーテニウム媒介のROMPが高度にシス型,高度に戦術的なポリマーを生成する最初の例を報告する.
- シス含有量と戦術性に対するモノマー構造の影響を調査する.
- エナティオメリックに純粋なモノマーから派生したポリマーの微細構造を探求する.
主な方法:
- リング開きメタテシスのポリメリゼーションのためにルテニウムベースの触媒を使用する.
- 様々なノルボネン誘導体からポリマーを合成する.
- cis含量と戦術性 (例えば,NMRスペクトロスコピー) を決定する技術を使用して,ポリマーマイクロ構造を分析する.
主要な成果:
- ルーテニウム媒介のROMPを成功裏に達成し,高シス含量 (場合によっては95%以上) と高戦術性 (95%以上) のポリマーを生産しました.
- cis含有量が特定のモノマー構造に依存することを示した.
- エナティオメリックに純粋な2,3-ディカルボアルコキシノルボナーディエンのポリメリゼーションにより,シンディオタクティックな微細構造が生じた.
結論:
- ルテニウム触媒は,ROMP経由で高度にシス,高度に戦術的なポリマーを合成するのに有効です.
- 開発された方法は,ポリマーの微細構造を正確に制御するための新しい経路を提供します.
- この進歩は,特異な性質を持つ高度な材料を作成する可能性を広げています.
関連する概念動画
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