Polymethine dyes derived from the boron difluoride complex of 3-acetyl-5,7-di(pyrrolidin-1-yl)-4-hydroxycoumarin

摘要

A boron difluoride complex of 3-acetyl-5,7-di(pyrrolidin-1-yl)-4-hydroxycoumarin was synthesized and converted into polymethine dyes which included an anionic,symmetric cyanine and several mer-ocyanine compounds.The spectral luminescent behaviour of the dyes was studied.As the electron-withdrawing ability of the 2,2-difluoro-1,3,2-dioxaborine ring was significantly reduced by the two pyrrolidino groups on the latter nucleus,the newly synthesized dyes exhibited changes in spectral parameters and much increased resistance to hydrolysis.