The Design,synthesis And Application Of Fluorescent Probes For Detection Of CO And Metal Ion(Au³⁺、Pd、Al³⁺)

Carbon monoxide（CO）,an important gaseous signal molecule,plays a crucial role in biological system.Metal ions(such as Au³⁺,Pd species and Al³⁺,etc.)were widely used in chemistry,biology,environmental sciences and other fields due to their unique properties,however,their excessive use will cause accumulation in the body and the environment,thereby causing a series of serious diseases and environmental pollution problems.Therefore,it is of great significance to develop excellent fluorescent probes for real-time monitoring of CO and metal ions in the environment and life systems.The main results of this dissertation are shown as follows:1.We have designed and synthesized a red-emitting fluorescent probe based on the Pd⁰-mediated Tsuji-Trost reaction for CO detection.The probe uses a coumarin derivative as a fluorophore and an allylcarbonate moiety as reaction site of CO.The response to CO was achieved through a Pd⁰-mediated Tsuji-Trost reaction-cyclization cascade reaction mechanism.It showed high fluorescence quantum yield（QY=0.238）,large Stokes shift（?λ=137 nm）,red emission(λ_ex/λ_em=471/608nm),high selectivity and anti-interference for CO,and has been successfully applied to the fluorescence imaging of CO in living cells and zebrafish.2.We have designed and synthesized a dual-functional fluorescent probe based on propynyl ether as the reaction site to simultaneously distinguish Au³⁺and different valence states（0,+2,+4）palladium species.The detection of Au³⁺by an irreversible C≡C hydrolysis reaction mediated to recognize Au³⁺.Meanwhile,it can detect all typical oxidation states（0,+2,+4）palladium species through the palladium-mediated depropynyl etherification reaction without adding additional reagents.Using different excitation and emission,the probe could simultaneously differentiate Au³⁺(λ_ex/λ_em=422/484 nm)and different valence states（0,+2,+4）palladium species(λ_ex/λ_em=472/606 nm),and was successfully applied for imaging Au³⁺and Pd⁰ in living cells.3.We have designed and synthesized a fluorescent probe with aggregation induced emission（AIE）characteristics for Al³⁺detection.The probe uses benzothiazole as the fluorophore,the O-phenolic hydroxyl group,the N-pyridine moiety and the C=N double bond are the binding sites of Al³⁺,this probe can be used to detect Al³⁺in almost wholly aqueous solution under mild conditions.The probe that detected Al³⁺has the advantages of good water solubility,high fluorescence quantum yield（QY=0.157）,good selectivity and high sensitivity（LOD=3.25 n M）.And it was successfully achieved imaging of Al³⁺in living cells and zabrafish.