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一个新系列的三明治型5.5'-乙烯:合成挑战,结构独特性和光动力学
Ming-Lun Pan1, Chao-Hsien Hsu2, Yan-Ding Lin2
1Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan.
Chemistry (Weinheim an der Bergstrasse, Germany)
|November 24, 2023
概括
新的双线性乙烯 (BLTP) 由于硬质障碍而表现出有限的旋转. 尽管有基态相互作用,但激发状态电子合是弱的,导致超快放松和无辐射.
科学领域:
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 双是重要的分子支架.
- 线性烯 (LTP) 具有独特的电子特性.
- 了解穿越空间 π-π (TSPP) 相互作用对于分子设计至关重要.
研究的目的:
- 合成和描述一系列新的双线性烯 (BLTP).
- 研究BLTPs的结构,电子和光物理特性.
- 探索受限制的C-C键旋转和TSPP相互作用对分子行为的影响.
主要方法:
- 对于BLTP合成的ter-butyllithium介导的循环.
- 进行X射线晶体学和密度函数理论 (DFT) 计算以进行结构阐明.
- 核磁共振 (NMR) 光谱学,循环电压测量和NICS(0) 计算用于电子属性评估.
主要成果:
- 取代了四乙烯的BLTPs非常拥挤,内部旋转受到限制 (>50 kcal/mol).
- 内分子TSPP相互作用显著影响基态特性 (NMR转移,氧化还原潜力,芳香度).
- 尽管C-C键受到限制,但LTP单元之间的兴奋状态电子合是弱的,导致单体状行为和通过兴奋子振动合的超快放松.
结论:
- BLTP是高效的蓝光吸收器,由于超快的放松动态,没有显著的辐射.
- 限制性C-C键旋转和TSPP相互作用在这些拥挤的分子的基本状态特性中起着至关重要的作用.
- BLTPs的激发状态行为由单体LTP单元主导,突出了激发-振动合的重要性.
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