合理的单体设计,用于通过直接异构结合聚合物合成合聚合物
Navnath R Kakde1,2, Himanshu Sharma3,2, Nitin V Dalvi1,2,4
1Polymer Science and Engineering Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India.
ACS polymers Au
|October 14, 2024
概括
设计具有缺电子核的双基单体,如二甲二胺 (NDI) 和二甲二胺 (PDI),有助于C-H激活聚合. 基于的单体需要更高的能量,这给合成带来了挑战.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
背景情况:
- 直接异构结合聚合是一种合成合聚合物的关键方法.
- 单体设计显著影响反应性和聚合结果.
- 缺乏电子的核心对于调整电子属性和启用C-H激活至关重要.
研究的目的:
- 为了研究在比西奥芬侧边单体中C-H激活的设计原理.
- 为了将单体结构与直接异构结合聚合的反应性相关联.
- 探索新型聚合物的合成,其中包括纳二胺 (NDI),二胺 (PDI) 和 (FLU) 单位.
主要方法:
- 密度函数理论 (DFT) 计算以确定C-H键抽象的能量需求.
- 质子NMR光谱学用于实验验证预测的反应性概况.
- 直接的异构结合聚合合成目标聚合物.
主要成果:
- DFT的计算显示,中央芳香核 (NDI,PDI,FLU) 的电子吸收强度决定了C-H键激活能量.
- 与烯侧面的单体相比,NDI和PDI侧面的单体对C-H激活的能量需求较低.
- 实验结果证实了DFT的预测,成功实现了NDI和PDI单体的聚合.
结论:
- 单体设计,特别是缺电子核心的选择,对于在直接异构关系中高效的C-H激活至关重要.
- 由于有利的能量概况,NDI和PDI是直接异性化聚合物的合适基石.
- 基单体对这种聚合法构成挑战,因为对C-H激活的能量需求更高.
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