Research On The Synthesis And Property Of Novel BODIPY Dyes

Boron-dipyrromethene (BODIPY) fluorophores have attracted much attention in the design of fluorescen labels and biomolecule sensors, because they present many excellent photospectral properties, such as high extinction coefficients (ε), high fluorescence quantum yields (φ_f) and good photostability. This kind of dyes are relatively easy to be oxidized and reduced, which leads to the BODIPY fluorophores' application in photo-switches based on the theory of electron or charge transfer (CT). Based on the recent development, this thesis was focused on preparing novel Boron-dipyrromethene dyes with strong fluorescence and long wavelength.The traditional synthesis of tri-pyrrole BODIPY dyes is that aldehydes were took as the starting materials, condensed with theα-H of a pyrrole and another 2, 2'-bipyrrole, oxidized by p-chloranll, then coordinated with BF₃. In this paper, aldehydes, acetyl chlorides andcarboxylic acids were taken as the starting materials, which condensed with excessive pyrrole in strong acid environment, then the resulting products coordinated with BF₃-etherate. The two steps can be performed in one-pot reaction, so the process was simplified.The absorbance spectrum, fluorescence spectrum, the absorption coefficients and quantum yield were detected. The relation between the photophysical properties and the structure of the dyes were investigated.A pH probe was obtained based on the fluorophore, the probe exhibits good properties as a pH fluorescent sensor with a 13-fold fluorescence enhancement in the pH range of 4.02—1.70. The selectivity for anions of dye 5 and dye 6 were detected and compared with that of the known dye 8. The results showed that the body structures of dyes were destroyed in strong basic environment.