高効率のアルミニウムを使用したラクチドのポリメリゼーションのメカニズム的側面
Carine Robert1, Thibault E Schmid1, Vincent Richard1
1Chimie ParisTech, PSL Research University, CNRS , Institut de Recherche de Chimie Paris, 75005 Paris, France.
Journal of the American Chemical Society
|April 12, 2017
まとめ
新しいアルミニウム触媒は,サレンリガンドによって安定させられ,室温でラクチドのリング開きポリメリゼーション (ROP) を効率的に開始します. 制御された性質を持つポリラクチドを生産するための シンプルで高効率な方法を提供しています
科学分野:
- ポリマー化学
- 有機金属化学
- カタリシス
背景:
- 環開きポリメリゼーション (ROP) は,ポリラクチドのような生物分解性ポリマーを合成するために不可欠です.
- ROPのための高度に活性でアクセシブルな触媒の開発は,重要な研究目標です.
- 既存の方法はしばしば複雑な触媒の準備と浄化を伴う.
研究 の 目的:
- ラクチドのROPのための新しい,高度に活性なアルミニウムベースのイニシアターについて報告する.
- 効率的なポリラクチド合成のためのシンプルで堅固な触媒システムを開発する.
- 計算的研究を用いて発現と伝播のメカニズムを解明する.
主な方法:
- C2対称サレンリガンドによって安定したアルミニウムイニシアターのインシット生成.
- 開発した触媒システムを用いてラックチドのリング開封ポリメリゼーション (ROP).
- 反応メカニズムを調査するための密度関数理論 (DFT) 研究.
主要な成果:
- アルミニウム-塩素複合体は,室温でララクチドROPに対する前例のない高い活性を示した.
- サラン複合体とオニウム塩から作る触媒システムは,ポリラクチドを良い収穫量で提供した.
- 制御されたポリメリゼーションを示す狭いポリ分散度インデックスは達成されました.
- DFTの研究では,開始と増殖の間に調整されたモノマーに対する外部アルコキシード攻撃が確認されました.
結論:
- ポリラクチド合成のための高効率でアクセシブルな触媒システムが開発されました.
- 新しい方法は複雑で高価な触媒の準備を避け,工業的に重要になります.
- 機械的洞察は,将来のポリメリゼーション触媒の設計のための基礎を提供します.
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