部分の合計より大きい: ヘテロ核ポリメリゼーション触媒
Jennifer A Garden1, Prabhjot K Saini1, Charlotte K Williams1
1Department of Chemistry, Imperial College London , London SW7 2AZ, U.K.
Journal of the American Chemical Society
|December 1, 2015
まとめ
新しい異核亜鉛 ((II) /マグネシウム ((II) 触媒は,エポキシード共聚化において優れた性能を示す. この新しい触媒は,二酸化炭素と無水素共ポリマー化の両方の同核触媒よりも著しく高い活性を示しています.
科学分野:
- 協調化学
- ポリメリゼーション触媒
背景:
- ホモディヌクレア触媒は,エポキシードと二酸化炭素/アンヒドリド共ポリマー化のために確立されています.
- これらの反応のための純粋な異核触媒は以前は知られていなかった.
研究 の 目的:
- 新しい異核亜鉛 (II) /マグネシウム (II) 複合体を合成し,特徴づけること.
- エポキシドコポリメリゼーションでの触媒性能を評価する.
主な方法:
- シンメトリックなマクロサイクリックリガンドを用いた異核Zn (II) /Mg (II) 複合体の合成.
- エポキシドと二酸化炭素または無水化物との共ポリマー化反応における触媒の活性および選択性の試験.
主要な成果:
- 異種核触媒は高ポリメリゼーション選択性と制御性を示した.
- ホモディヌクレア類と比較して,著しく高い活性を示した.
- 具体的には,同核複合体の50:50の混合物と比較して,CO2/エポキシドの5倍,およびアンヒドリド/エポキシド共聚化の40倍以上の活性を示した.
結論:
- 開発された異種核Zn (II) /Mg (II) 触媒は,エポキシド共聚化のための高度に活性で選択的な触媒の新しいクラスを表します.
- この発見はポリマー合成のための効率的な触媒を設計するための新しい道を開きます.
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