Synthesis And Properties Of Cyanide Fluorescent Probes

Cyanide does great damage to the organism and environment as an toxic substance. Butit still widely exists in nature and various industries. Therefore, it’s considerable interest tofind highly selective probes for cyanide anions. In this thesis, four series of fluorescent probes(Sciff’s base series, dipyridyamine auron series, hydroxy aurone series and pyridinium innersalt series) have been designed and synthesized based on strong fluorescence properties ofaurone and pyridinium salts compounds. Thirteen compounds were synthesized and theirlinear photophysical properties, two-photon fluorescence properties and cyanide recognitionproperties were systematically examined. In chapter two to four, the synthesis, photophysicalproperties (linear absorption properties, single-photon fluorescence properties and two-photonfluorescence properties) and cyanide recognition properties of all the compounds werereported．In chapter five, the properties between the different compounds were summarizedand contrasted.The title compounds are classified to four series according to structural characteristic:Series1: Sciff’s base series1and2Series2: dipyridyamine aurone series3-5Series3: hydroxy aurone series6-8 Series4: pyridinium inner salt series9-131. Synthesis and characteristic of the compounds: Thirteen compounds of four seriesabove were synthesized. All of the compounds are stable in solid state or common organicsolvents. The crystal structures of seven compounds were obtaine.2. Photophysical properties of the compounds: The photophysical properties includingabsorption properties and fluorescence properties of the compounds were examined. Inaddition, the photophysical properties between the different compounds were contrasted. Theinvestigation indicate that solvent polarity, number of branches and terminate group affectsthe photophysical properties of the compounds.3. Cyanide recognition properties：In this thesis, thirteen compounds were synthesizedand eight of them have response to cyanide. Six compounds achieved“naked-eye”detectioncyanide in natural light. Compounds3-5exhibit fluorescence turn-on recognization forcyanide and a degree of repeatability and good selectivity for CN-in CH3CN. It’s worthmentioning that compound12and compounds6-8exhibit good selectivity for CN-in aqueoussolution. The detection limit of compound12in aqueous solution for CN-below1.9μM,which is the maximum permissive level of cyanide in drinking water regulated by WorldHealth Organization.