Synthesis And Properties Of 1,2 - Benzo-pyrone Derivatives

The agent concentration is an important detection parameter in industrial recirculating water,so it is significant to detect the agent concentration in water rapidity. The fluorophore is included in the structure of fluorescence-lablelled water treatment agent,it can be detected rapidly and accurately by fluorescence examination.The optimum bromination reaction conditions of 7-acetoxy-4-methyl-2H-chromen-2-one were obtainned by single facter and peprendieular experiment.Then a quaternary ammonium-salt,dimethyl-(4-(7-acetoxyl-2H-chromen-2-one))-methyl-(2-acrylate)-ethyl-amm onium bromide,was synthesized by quaternaristion using 4-(bromomethyl)-7-acetoxy-2H-chromen-2-one (Br-MAC) and N,N-Dimethylaminoethyl acrylate.the bromination reaction conditions of 7-methoxy-4-methyl-2H-chromen-2-one is also studied.Three kinds of brominated products,7-methoxy-4-bromomethyl-2H-chromen-2-one,7-methoxy-4-methyl-3-bromo-2H-chromen-2-one and 7-methoxy-4-bromomethyl-3-bromo-2H-chromen-2-one were synthesized by controlling reaction condition such as the amount of initiator,reaction time and light.The structure of brominated products and the quaternary ammonium salt were characterized by FT-IR and NMR.The crystal structures of 4-(bromomethyl)-7-acetoxy-2H-chromen-2-one and 7-methoxy-4-methyl-3-bromo-2H-chromen-2-one were determined by Bruker-P4 diffractometer.The fluorescence property of the monomer was characterized by fluorescence spectrophotometer;the anti-corrosion property was characterized by electrochemistry workstation.The results shoued that the calibration curve for the determination of the monomer was linear over the range from 1×10^-2mg/L to 20×10^-2mg/L.The fluorescent intensity of are constant at pH=7-10;the quaternary ammonium salt was proved to have positive inhibiting effect and high inhibiting efficiency by electrochemical test.