Liu Huijing, Yan Sisi, Huang Rongrong, Gao Zhipeng, Wang Gang, Ding Liping, Fang Yu
Key Laboratory of Applied Surface and Colloid Chemistry of, the Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710062, P.R. China.
School of Textile Science and Engineering, Xi'an Polytechnic University, Xi'an, 710048, P.R. China.
Chemistry. 2019 Dec 20;25(72):16732-16739. doi: 10.1002/chem.201904478. Epub 2019 Dec 6.
The search for structurally simple chromophores with superior fluorescence brightness and a wide range of solvent compatibility is highly desirable. Herein, a new type of single-benzene-based solvatochromic chromophore with a symmetric bifunctional structure, in which azetidine and ethoxycarbonyl moieties serve as the electron-donating and -withdrawing groups, respectively, is reported. This chromophore exhibits an extraordinary wide range of solvent compatibility and preserves excellent fluorescence quantum yields from nonpolar n-hexane to polar methanol and even in water. Unusually, the symmetric structure of the chromophore shows a distinct color change from bright green to red with increasing solvent polarity and possesses large Stokes shifts (λ=132-207 nm) in the tested solvents. Moreover, this single-benzene-based chromophore displays good photochemical stability in both solution and solid states, and even exhibits reversible mechanochromic luminescence.
寻找具有优异荧光亮度和广泛溶剂兼容性的结构简单的发色团是非常必要的。在此，报道了一种新型的具有对称双功能结构的单苯类溶剂致变色发色团，其中氮杂环丁烷和乙氧羰基部分分别作为供电子基团和吸电子基团。该发色团表现出极其广泛的溶剂兼容性，并且从非极性的正己烷到极性的甲醇甚至在水中都保持优异的荧光量子产率。不同寻常的是，该发色团的对称结构随着溶剂极性的增加呈现出从亮绿色到红色的明显颜色变化，并且在测试溶剂中具有较大的斯托克斯位移（λ = 132 - 207 nm）。此外，这种单苯类发色团在溶液和固态中均表现出良好的光化学稳定性，甚至还表现出可逆的机械变色发光。
