プロピレン酸化物とラクチドがポルフィリンクロム (((III)) センターで結合する
Vagulejan Balasanthiran1, Chandrani Chatterjee, Malcolm H Chisholm
1Department of Chemistry and Biochemistry, The Ohio State University , 100 West 18th Avenue, Columbus, Ohio 43210, United States.
Journal of the American Chemical Society
|January 29, 2015
まとめ
5,10,15,20-テトラフェニルポルフィリンクロミウム塩化物 (TPPCrCl) とPNP ((+) Cl ((-)) は選択的に乳酸塩をポリラクチドにポリメリ化する. ステレオセレクティビティは温度に依存し,低温は高同位性ポリマーを生成し,高温は副作用を引き起こす.
科学分野:
- ポリマー化学のポリマー化学について
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- ポリラクチド (PLA) は,生物分解性ポリマーで,さまざまな用途があります.
- ラクチドの制御されたポリメリゼーションは,PLAの特性を調整するために不可欠です.
- ステレオ選択的ポリメリゼーションは,PLAの物理的および分解特性に影響を与えます.
研究 の 目的:
- 5,10,15,20-テトラフェニルポルフィリンクロミウム塩化物 (TPPCrCl) とPPN ((+) Cl ((-)) を用いて乳酸塩のステレオ選択的ポリメリゼーションを調査する.
- ポリメリゼーションの選択性および副作用に対する温度の影響を決定する.
- PLA形成のメカニズムと潜在的副産物を調査する.
主な方法:
- ラクチド (L-とrac-LA) の環開きポリメリゼーションはTPPCrCl/PPN(+) Cl(-) によって開始される.
- ポリメリゼーションは,様々な温度 (0 °C, 25 °C, 60 °C+) で,きれいなプロピレン酸化物 (PO) 溶媒で実施されます.
- ポリマーのステレオ化学 (同位性) と副産物形成の分析.
主要な成果:
- TPPCrCl/PPN(+) Cl(-) は,特定のエンドグループ (-OCHMeCH2Cl) を有する乳酸をPLAに効率的にポリマー化します.
- 0°C以下では,ラセミック・ラクチド・ポリメリゼーションにより,高度にイソタキシ性のあるPLA (IIIテトラドで濃縮) が得られます.
- 高温 (25°C+) により,重要なトランスエステル化とPO連鎖によりステレオ選択性が低下し,3,6-ジメチル-1,4-ダイオキサン-2-オンが形成されます.
結論:
- TPPCrCl/PPN(+) Cl(-) は,ステレオ選択性乳酸ポリメリゼーションのための効果的な触媒システムです.
- PLA合成における高同毒性を達成するために,温度制御は極めて重要です.
- POエンチェインメントのような副作用を理解することは,PLAの生産と特性を最適化するために重要です.
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