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低圧CO2/エポキシードリング開封共ポリメリゼーションのためのインジウム触媒:単核機構の証拠?
Arnaud Thevenon1, Anish Cyriac2, Dominic Myers2
1Department of Chemistry , University of Oxford , 13 Mansfield Road , Oxford OX1 3TA , United Kingdom.
Journal of the American Chemical Society
|May 22, 2018
まとめ
新しいインジウム触媒は,一種の単核経路を通じて二酸化炭素とエポキシドの効率的な共聚化を可能にします. これらのフォスファサレン複合体は,高い選択性を達成し,主要な中間物質の特徴づけを可能にします.
科学分野:
- ポリマー化学
- 有機金属化学
- カタリシス
背景:
- 二酸化炭素 (CO2) とエポキシドの交互の共ポリメリゼーションは,ポリマー合成におけるCO2利用に不可欠である.
- 既存の触媒経路は典型的には二金属または二成分であり,機械的理解を制限している.
- 代替反応メカニズムを探求するために新しい触媒の開発が必要である.
研究 の 目的:
- CO2 /エポキシード共聚化のための最初のインジウム触媒を導入する.
- 単核触媒経路を明らかにする
- 重要な触媒介質を特徴づけ,その協調行動を理解する.
主な方法:
- フォスファサレン結合インジウム複合体の合成と特徴付け
- 低CO2圧力 (1バー) の下での触媒活動の調査
- 触媒介質 (アルコ酸化物と炭酸化合物) の分離とスペクトル分析
- 運動研究と現地スペクトル観測
主要な成果:
- インジウムフォスファサレン複合体は,CO2 /エポキシード共ポリマー化において高い活性と選択性 (> 99% の炭酸結合, > 70% の同選択性) を表している.
- 触媒は1バーのCO2圧力でコカタリスタなしで効率的に動作します.
- 単核アルコシド (ペンタコーディネート) と炭酸塩 (ヘクサコーディネート) の中間物質を分離し,特徴づけました.
- 動的データと in situ 試験は,第1次は触媒濃度,第0次はCO2圧力に依存する単核経路を確認している.
結論:
- インジウム触媒,特にフォスファサレン複合物は,CO2 /エポキシード共聚化における新しい単核経路で動作する.
- 中間物質を分離し特徴づける能力は 触媒サイクルに希少な洞察を与えてくれます
- この研究は,単核メカニズムで働くために,潜在的により大きな金属を使用する他の均質な触媒を設計するための道を開きます.
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