Synthesis of new porphyrins with dicyanopyrazine moiety and their optical properties

摘要

5,10,15,20-Tetra[5-{2-(4-alkoxyphenyl)-ethenyl}-6-{2-phenyl-ethenyl}-2,3-dicyano-pyrazino]-porphyrin (5) was prepared by the condensation reaction of pyrrole and a bis-styryl derivative (4) containing 2,3-dicyanopyrazine.The existence of a strong intramolecular charge-transfer chromophoric system was confirmed for dyes 5,and its large Stokes shift of over 200 nm resulted in the emission of red fluorescence.The chro-mophoric systems of these dyes were studied from the viewpoint of the protonation and deprotonation effects on their absorption and fluorescence spectra in solution.