Ding Ge, Wang Xinchao, Li Xiujuan, Liu Hongpan, Wang Lunxiang, Liu Na, Gao Fang, Wang Zhenqiang
College of Materials and Chemical Engineering, Chongqing University of Arts and Sciences Chongqing China 402160
College of Pharmacy, Heze University Heze Shandong Province China 274000
RSC Adv. 2019 Nov 6;9(62):36097-36102. doi: 10.1039/c9ra07290j. eCollection 2019 Nov 4.
The non-fluorescent Schiff base compound C1 ('-((4'-ethyl-3-hydroxy-[1,1'-biphenyl]-4-yl)methylene)furan-2-carbohydrazide) in organic solvent (, THF) was found to produce yellow-green fluorescence emission upon addition of HO, and granular-shaped aggregates in a THF/HO mixed solution formed and exhibited obvious aggregation-induced emission (AIE). Especially its keto fluorescence band intensified dramatically, while the enol emission band remained almost unchanged. Hence, a change in fluorescence from no emission of light to emission of bright yellow-green light under a UV lamp was observed with the naked eye. In contrast, the reference compound C2 ('-((4'-ethyl-3-methoxy-[1,1'-biphenyl]-4-yl)methylene)furan-2-carbohydrazide) showed no intensified fluorescence emission under the same experimental conditions. These results indicated the significant role played by intramolecular H-bonding in the formation of the C1 aggregates and the AIE process.
在有机溶剂（如四氢呋喃，THF）中的非荧光席夫碱化合物C1（' - （（4'-乙基-3-羟基-[1,1'-联苯]-4-基）亚甲基）呋喃-2-碳酰肼）在加入过氧化氢（HO）后被发现会产生黄绿色荧光发射，并且在四氢呋喃/过氧化氢混合溶液中形成颗粒状聚集体并表现出明显的聚集诱导发光（AIE）现象。特别是其酮式荧光带显著增强，而烯醇式发射带几乎保持不变。因此，肉眼可观察到在紫外灯下荧光从无发光变为发出亮黄绿色光的变化。相比之下，参考化合物C2（' - （（4'-乙基-3-甲氧基-[1,1'-联苯]-4-基）亚甲基）呋喃-2-碳酰肼）在相同实验条件下未显示出荧光发射增强。这些结果表明分子内氢键在C1聚集体形成和AIE过程中发挥的重要作用。
