Abstract: Carbonyl chlorides substituted with aromatic dense ring are chemically active and their fluorescent quantum yields are usually high and they may be used as fluorescent probes for detection of many compounds. Studies on their synthesis and structure activity relationship are very important in the micro or supermicro detection of drugs and toxicants containing hydroxy groups. Therefore, the probes may find wide application in the fine chemical engineering and pharmaceutical industry. Three new fluorescent probes: β-(9-anthracene) acrylonyl chloride, β-(9-anthracene) propionyl chloride and β-(1-pyrene) acrylonyl chloride were synthesized by the reaction between the corresponding acid and thionyl chloride. 1 Pyrenecarboxaldehyde synthesized by using pyrene and N-formyl-N-methylaniline with phosphorus oxychloride as catalyst, was allowed to react with malonic acid to produce β-(1-pyrene) acrylic acid for the last mentioned acid chloride.