Decorating BODIPY with Electron-Rich Unit THDTAP: An ICT-Based Fluorometric Sensor toward Peroxide, Acid, and Electrochemical Stimuli
Decorating BODIPY with Electron-Rich Unit THDTAP: An ICT-Based Fluorometric Sensor toward Peroxide, Acid, and Electrochemical Stimuli
复制标题
用富电子单元 THDTAP 装饰 BODIPY：一种基于 ICT 的过氧化物、酸和电化学刺激荧光传感器
DOI：
10.1016/j.dyepig.2019.04.069
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发表时间：
2019
影响因子：
4.5
通讯作者：
Shao Xiangfeng
中科院分区：
文献类型：
--
作者：
Xu Taoshan;Yan Chaoxian;Wu Yuewei;Yuan Chengshan;Shao Xiangfeng
将富含电子的THDTAP单元修饰到BODIPY的基座上，合成了一种新型的具有施主-受体(D-A)结构的BODIPY染料化合物2。THDTAP有两个化学活性中心(S和N原子)，用于操纵光电性质。通过用m-CPBA逐步氧化THDTAP部分上的两个原子，2转化为3、反式-4、5和6。这种转变对光电性能有很大的影响。理论计算表明，2-6的Lumo都位于BODIPY核上，而它们的Lumo呈现不同的分布。通过TD-DFT计算、吸收带和发射带的红移和溶致变色，证明了化合物2和3发生了分子内电荷转移(ICT)转变。由于THDTAP部分上FS原子的高氧化态，INAN-4、SYN-4、5和6中的ICT过程受到抑制。结果表明，这四种化合物具有BODIPY的特征荧光。飞秒瞬时吸收光谱研究表明，2在二氯甲烷(DCM)溶液中表现为光致空穴转移(PHT)过程。在THDTAP部分上n原子的酸化和中和后，可逆地操纵DCM中2的ICT/PHT过程，从而导致BODIPY核心的荧光开/关。此外，通过THDTAP部分上的n原子的电化学氧化，BODIPY核心区2上的荧光也可以被开启。因此，化合物2是一种对过氧化氢、酸和电化学刺激有希望的荧光传感器。
A new type of BODIPY dye, compound2which possesses donor-acceptor (D-A) type structure, is synthesized by decorating electron-rich THDTAP unit onto themeso-position of BODIPY. The THDTAP has two chemically active sites (S and N atoms) that are utilized to manipulate the optoelectronic properties. By stepwise oxidation of twoS-atoms on THDTAP moiety withm-CPBA, the2was converted to3,trans-4,syn-4,5, and6. This transformation results in large influence on optoelectronic properties. The theoretical calculations reveal that the LUMOs of2–6are all located on BODIPY core, whereas their HOMOs show the different distributions. The2and3show the intramolecular charge-transfer (ICT) transition as proved by TD-DFT calculations, red-shifts of absorption and emission bands, and solvatochromism. The ICT process is inhibited intrans-4,syn-4,5, and6due to the high oxidation states ofS-atoms on THDTAP moieties. As a result, these four compounds display characteristic fluorescence of BODIPY. The femtosecond transient absorption (fs-TA) spectroscopic study reveals that2shows photoinduced hole-transfer (PHT) process in dichloromethane (DCM) solution. Upon acidification and neutralization ofN-atom on THDTAP moiety, the ICT/PHT process of2in DCM is reversibly manipulated to result in fluorescence ON/OFF of BODIPY core. Moreover, the fluorescence of BODIPY core on2can be switched on through electrochemical oxidation ofN-atom on THDTAP moiety. The compound2is thus a promising fluorometric sensor toward peroxide, acid, and electrochemical stimuli.