DFT研究了与基结合不同类单体的抽取反应中的溶剂效应
Xiaotian Zhao1, YaMing Li2, Shibo Lin1
1Department of Pharmacy, Chengdu Second Peoples Hospital, Chengdu, 610017, People's Republic of China.
BMC chemistry
|September 12, 2023
概括
基乙烯单体通过光驱动 [3+2] 循环加速聚合. 溶剂的选择显著影响吸收反应速率,解释了悬浮光聚合的反应性差异.
科学领域:
- 聚合物化学 聚合物化学
- 光聚合的光聚合方式.
- 计算化学计算化学
背景情况:
- 众所周知,基类单体具有降低的降解链转移.
- 光驱动的 [3+2] 循环化加速了聚合.
- 基乙烯单体在悬浮光聚合过程中表现出更高的反应性.
研究的目的:
- 研究溶剂对类单体中抽象反应 (HAR) 的影响.
- 阐明控制含有氧,和硫原子的单体的不同反应性的因素.
- 了解通过光诱导循环的加速聚合的机制.
主要方法:
- 运用量子化学计算来研究甲醇,水和DMSO中的HAR.
- 利用静电电位 (ESP) 和拓分析 (ELF,LOL) 进行轨道调查.
- 应用了扭曲模型,过渡状态理论和独立梯度方法 (IGMH) 来研究分子相互作用和反应动态.
主要成果:
- 在 500-2500 K 的温度范围内,确定了抽取的反应速率常数.
- 确定了溶剂效应作为影响哈尔的速率和机制的关键因素.
- 埃卡特的校正揭示了抽象反应道的驱动因素.
结论:
- 溶剂特性极大地影响抽象反应速率,解释了类单体反应活性观察到的差异.
- 这项研究提供了通过 [3+2] 循环化加速光聚合的机制性理解.
- 研究结果为设计和优化光聚合过程提供了洞察力.
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