长距离穿越太空的电荷转移在一个响应pH的里丁和里烯混合旋风炉中
Parisa Ghods Ghasemabadi1, Zahra A Tabasi1, Parinaz Salari1
1Chemistry Department, Memorial University of Newfoundland, 45 Arctic Avenue, St. John's, NL A1C 5S7, Canada.
Chemistry (Weinheim an der Bergstrasse, Germany)
|September 8, 2023
概括
研究人员合成了一种新的旋风,它结合了氨酸和氨酸. 质子化诱导电荷转移,在这种紧张的分子架构中揭示了独特的穿越空间的电子相互作用.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 光物理学的光学物理学
背景情况:
- 旋为研究分子相互作用提供了独特的结构支架.
- 含有芳香单元的混合环芳素为新型电子性质提供了机会.
- 桥式烯因硬质障碍而难以合成.
研究的目的:
- 为了合成一种新的,大型的,并且形状灵活的混合二烯和二烯旋.
- 为了研究在旋中质子化氨酸单元的电子和结构后果.
- 探索穿越太空的分子内电荷转移相互作用.
主要方法:
- 通过两个分子内合反应合成.
- 一个前所未有的Scholl反应对不反应的pyrene 2-位置.
- 结构特征和计算分析 (θcalc = 162.6°).
- 紫外线-Vis吸收光谱检测电荷传输带.
主要成果:
- 成功合成了一种三重桥接的pyrenophane,其中包括pyridine和teropyrene单元.
- 皮里丁部分的质子化显著增强了其在铁皮林腔内的嵌套.
- 在质子化时出现一个明显的电荷转移吸收带 (λmax = 592 nm).
- 证据表明,皮里迪尼和特罗皮烯之间存在长距离 (5.0-5.5 Å),穿越空间的分子内转换.
结论:
- 合成的混合旋风具有独特的形状灵活性和应变 (SE=44.2 kcal/mol).
- 质子化触发了重要的结构重组,并使电荷转移成为可能.
- 展示了超分子系统中通过空间进行电子通信的新机制.
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