鉄トリス (((ディベンゾイルメタン)) を中心とするポリラクチド星:乳酸塩環開きポリメリゼーションにおける金属複合体の複数の役割
Jessica L Gorczynski1, Jianbin Chen, Cassandra L Fraser
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
Journal of the American Chemical Society
|October 27, 2005
まとめ
鉄複合体は,ポリ (乳酸) 合成を改善する. 保護基と触媒として鉄 (III) を使用すると,反応時間は大幅に短縮され,乳酸塩ポリメリゼーションにおける分子量制御が強化され,高度なバイオマテリアルが生成されます.
科学分野:
- ポリマー化学のポリマー化学について
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
背景:
- ポリ乳酸 (PLA) とその金属複合物は,バイオマテリアルおよび触媒として有望である.
- ハイドロキシル機能化されたディベンゾイルメタン (dbmOH) イニシアターによるSn(oct) 2を用いた伝統的な乳酸塩ポリメリゼーションは遅いもので,分子量制御は限られている.
研究 の 目的:
- ラクチド環開きポリメリゼーションの効率と制御を強化するために.
- PLA合成のイニシアターおよび触媒として鉄 (III) 複合体の使用を調査する.
主な方法:
- ハイドロキシル機能化されたディベンゾイルメタン (dbmOH) をイニシアターとして使用したラクチド環開きポリメリゼーション.
- 鉄 (III) を使ってFe (dBmOH) 3を三機能メタロイニシアターおよび触媒として形成する.
- dbmOHとベンジルアルコールのイニシアターによる触媒としての鉄トリシス (dbm) と鉄トリシス (acac) を調査.
主要な成果:
- Fe (((dbmOH) 3は,Sn (((oct) 2. 2と比較して,ポリメリゼーション時間を10分に大幅に短縮し,分子量制御を改善しました.
- 鉄を中心としたポリマー (Fe(dbmPLA) 3) は,亜鉛触媒なしででも,低ポリ分散度指数 (PDI <1.1) で合成されました.
- 鉄の触媒は,酸処理によってポリメリゼーション後効果的に除去され,さらなる機能化のために非金属化されたPLAが得られました.
結論:
- 鉄 (III) ベータ・ディケトネート複合体は,優れた制御で迅速なPLA合成のための非常に効果的なイニシアターと触媒です.
- このアプローチは,バイオマテリアルおよび触媒用途の機能的なPLA材料への多用途の経路を提供します.
- 鉄複合体は,ラクチドポリメリゼーションにおける従来の亜鉛触媒の再生可能で効率的な代替品を提供します.
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