Synthesis And Spectral Properties Study Of Chemosensors Based OnRhodamine Modified By Coumarin

Metal ions play an important role in the organism, excess or absence of certain metal ions can cause various diseases. However, the awareness of environmental protection of human is still relatively weak, using improperly or discarding waste will lead to excessive metal ions in water, soil and atmosphere at the same time. As a result, metal ions content in organisms will lose balance, which may be dangerous to our life. Therefore, designing a method for rapid detection of metal ions is imminent. Photochemical sensor have many advantages of metal ions’recognition, such as highly sensitivity, good selectivity, low detection limits and fast detection, thus photochemical sensors have become the hot spot in current research. At present, a photochemical sensor could identify various metal ions have been reported quite a lot, but they were just the same kind of fluorescence or UV signal under the single recognition, which limits their application. Thus, to design the chemosensors can identify different metal ions in different fluorescence or UV signal is still a challenging task. Based on the above considerations, we designed and synthesized three different photochemical sensor Li, L2and L3. The study found that, Li and L2could identify Ca2+and Al3+in different fluorescence signal, L3could be used for the orderly naked eye recognition of Cu2+and Hg2+. This paper mainly contains three parts:1. The photochemical sensors are introduced briefly, and then we discussed the different recognition mechanism of the photochemical sensor in detail. At last, we focused on the research progress of multi signal optical sensor and the significance of this work.2. We designed and synthesized two fluorescent chemosensors (Li and L2) based on coumarin-modified rhodamine derivative. Compound Li and L2was capable of the selective fluorescent recognition of Al3+and Ca2+ions, giving rise to a different fluorescent signal for each metal ion under the same conditions. At the same time, the structure of compound Li and L2were characterized by NMR, X-ray、HRMS. The binding ratios of the compounds and metal ions were both2:1according to the Job’s plot and high resolution mass spectrometer (HRMS) experiments. In addition, the binding mode of compounds with metal ions were also studied with lH NMR and FTIT. Finally, bioimaging results also demonstrated that compound Li could act as an intracellular Al3+ion imaging sensor.3. Photochemical sensor L3, as a naked eye sensor for the recognition of Cu2+and Hg2+, was designed and synthesized. The structure of compound L3were characterized by ’HNMR,13CNMR, FT-IR, HRMS. We studied the spectral properties of the probe by UV spectra and found that this procedural sensor L3could be used for the orderly naked eye recognition of Cu2+and Hg2+. At last, the binding ratios of the compounds L3and Cu2+was1:1according to Job’s Plot, HRMS. The recognition mechanism was simply discussed in this paper by FT-IR, NMR titration experiments.