溶解度平衡辅助的动态分辨率聚合,用于含有轴性的同位体聚合物
Qing Cao1, Hua-Zhong Fan1, Min Xie1
1National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, Sichuan University, 29 Wangjiang Rd, Chengdu 610064, P. R. China.
Journal of the American Chemical Society
|December 16, 2024
概括
研究人员开发了用于对rac-Me-DBO的立体控制聚合物的新型催化剂. 利用可溶性平衡显著提高了聚合物战术性,达到高同位性P ((Me-DBO) 的Pm高达0.93.
科学领域:
- 聚合物化学
- 催化剂
- 立体化学
背景情况:
- 实现对聚合物立体化学的高水平控制对于定制材料特性至关重要,但在合成聚合物化学中仍然是一个重大挑战.
- 轴性催化剂为立体控制的聚合提供了一个有前途的途径.
研究的目的:
- 用于对rac-Me-DBO进行立体控制的聚合,制备带有轴性双基的新型催化剂.
- 研究催化剂结构和反应条件对聚合物的立体选择性的影响.
- 开发一种用于增强聚合物的立体控制的多功能策略.
主要方法:
- 合成新型的硫催化剂,其中包括轴性性双单元.
- 使用开发的催化剂对rac-Me-DBO进行动态分辨率聚合.
- 利用可溶性平衡来维持单体度.
- 机械研究以阐明聚合途径.
主要成果:
- 通过动态分辨率,具有较大的双基的 (S) - Y3催化剂实现了中等的同选择性 (Pm高达0.80).
- 使用溶解平衡来控制单体度显著提高了聚合同选择性.
- 获得高同位性P (Me-DBO) 产品的战术性 (Pm) 达到了0.93.
- 机械研究证实了溶解度-平衡转移假设.
结论:
- 采用可溶性平衡辅助运动分辨率聚合的新策略得到了成功开发.
- 这种方法在不需要新的催化剂设计的情况下增强聚合物的立体控制.
- 开发的战略预计将成为改进聚合物立体化学的多功能平台.
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