通过立体电子相互作用调整超分子聚合物组件
Will R Henderson1, Guancen Liu1, Khalil A Abboud1
1George & Josephine Butler Polymer Research Laboratory, Center for Macromolecular Science & Engineering, Department of Chemistry, University of Florida, P.O. Box 117200 Gainesville, Florida 32611-7200, United States.
Journal of the American Chemical Society
|August 4, 2021
概括
通过胺结实现了新型二氧化的超分子聚合. 硫的氧化到硫增强了轨道相互作用,推动了聚合物组装和延长.
科学领域:
- 超分子化学
- 有机化学
- 材料科学
背景情况:
- 超分子聚合提供了具有可调节性质的新材料的途径.
- 键是一种关键的非共价相互作用驱动自组合.
- 帕拉cyclophanes为分子设计提供独特的结构支架.
研究的目的:
- 为了研究2,11-dithia[3.3]paracyclophanes的高分子聚合.
- 阐明分子间和跨环胺结合在驱动聚合中的作用.
- 探索立体电子效应,特别是n → π*相互作用对聚合物组装的影响.
主要方法:
- 2,11-dithia[3.3]paracyclophanes的合成和表征
- 用光谱分析 (NMR,IR) 来研究结和聚合.
- 进行X射线结晶学以确定结构变化.
- 计算化学 (DFT) 研究电子相互作用和模型系统.
主要成果:
- 通过自我补充的氨基酸结合成功的超分子聚合.
- 涉及桥梁硫原子的 n → π* 相互作用的识别.
- 氧化到硫增强了n → π*相互作用,导致聚合和延长的增加.
- 实验证据 (延长常数,振动频率,晶体学) 支持立体电子效应的作用.
结论:
- 2,11-dithia[3.3]可通过氨基酸结合进行超分子聚合.
- 这种 n → π* 相互作用对于组装至关重要,并且可以通过硫氧化来调节.
- 立体电子效应显著影响了超分子聚合物形成的效率和程度.
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