通过密集替代氨基酸指定的rac-Lactide的环开聚合
Ana Sanchez-Sanchez1, Ivan Rivilla2, Maddalen Agirre2
1POLYMAT, University of the Basque Country UPV/EHU , Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia/San Sebastian, Spain.
Journal of the American Chemical Society
|March 9, 2017
概括
化器官催化剂可实现对rac-lactide进行立体控制的环开聚合,从而实现高同位性聚合物丰富. 催化剂选择性聚合l-或d-乳化物,证明有效的性转移.
科学领域:
- 聚合物化学
- 有机合成
- 催化剂
背景情况:
- 有机催化剂为聚合物合成提供了一种多功能和特定的方法.
- 使用有机催化剂的立体控制聚合仍然是一个挑战,只有有限的性转移例子.
- 乳化物的环开聚合 (ROP) 对于生物降解聚合物生产至关重要.
研究的目的:
- 在rac-lactide的ROP过程中,从有机催化剂转移到聚合物.
- 研究特定的性氨基酸衍生物的立体选择性聚合能力.
- 使用计算方法阐明立体控制的机械起源.
主要方法:
- 有机催化环开放聚合物 (ROP) 的rac-LA.
- 使用二聚体氨基酸衍生物 (endo-6和exo-6) 与1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) 作为联合催化剂.
- 使用密度函数理论 (DFT) 计算来探索聚合机制.
主要成果:
- 在室温下实现同位素聚酸的合成,其立体化学纯度 (Pm) > 0.90.
- 通过特定的催化剂二态异构体 (l-LA 的 exo-6,d-LA 的 endo-6) 证明了 l-乳酸或 d-乳酸的优先聚合.
- DFT计算提供了关于催化剂性决定单体插入立体化学的见解.
结论:
- 基拉性氨基酸衍生器官催化剂可以在ROP期间有效地将基拉性转移到聚酸中.
- 催化剂的特定二聚体决定了rac-LA聚合的立体化学结果.
- 这项研究介绍了一种在先进材料中具有潜在应用的聚胺立体选择合成的新方法.
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