在室温溶液中激发状态的分子内硫醇质子转移的章节开启
Chun-Hsiang Wang1, Zong-Ying Liu1, Chun-Hao Huang2
1Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.).
Journal of the American Chemical Society
|August 6, 2021
概括
研究人员首次通过实验观察了溶液中的硫醇质子的激发状态内质子转移 (ESIPT). 这项关于3-thiolflavone衍生物的研究揭示了ESIPT反应涉及硫的新途径.
科学领域:
- 摄影化学
- 超分子化学
- 有机化学
背景情况:
- 激发状态内质子转移 (ESIPT) 是一个重要的光物理过程.
- ESIPT通常涉及O-H或N-H转移,但S-H转移的研究较少.
- 了解ESIPT机制对于设计新型光响应材料至关重要.
研究的目的:
- 通过实验证明涉及醇质子的激发状态内质子转移 (ESIPT).
- 研究3黄衍生物的光物理性质,特别是3NTF.
- 阐明在室温下含硫化合物的ESIPT机制.
主要方法:
- 合成3-黄衍生物,包括3NTF及其甲基化对应物3MeNTF.
- 在循环中进行稳定状态吸收和排放光谱.
- 时间分辨率的光光谱.
- 计算化学方法 (DFT).
主要成果:
- 在3NTF中实验性观察类ESIPT,以710 nm的大型斯托克斯移排 (12,230 cm−1) 为证据.
- 与3MeNTF进行比较,它缺少硫醇质子,在472nm处显示正常发射.
- 超快速的ESIPT速率 (<180 fs) 和3NTF的保温体发射寿命为120 ps.
- 计算研究证实ESIPT在热学上有利,但揭示了非发射衍生物的非辐射衰变途径.
结论:
- 对于室温溶液中的二醇型ESIPT的明确实验证据.
- 在激发状态下,3NTF中的二甲基氨基基组促进ππ*的特性,使得突出的体排放成为可能.
- 这项工作扩大了ESIPT化学的范围,包括非正规的硫键.
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