Synthesis, absorption and fluorescence spectral investigation of porphyrazines with eight 9-anthracenecarboxy esters

Abstract

Magnesium porphyrazines substituted with eight 9-anthracenecarboxy groups on the peripheral positions have been synthesized by esterification of octakis(hydroxyethylthio) derivative with 9-anthracenecarboxylic acid. Metal-free derivative as well as zinc porphyrazine were also isolated. These porphyrazines have been characterized by elemental anaysis, H-1 NMR, C-13 NMR, U.v.-vis. spectral data. In the case of compounds carrying porphyrazine and anthracene entities together in the same molecule and also in the case of mixtures made up of these electron-rich moieties, the emission of anthracene has been quenched by the porphyrazine core. The detected emission is related only to porphyrazine. Therefore, in both cases energy transfer has been realized from electronically excited anthracene (donor) units to the porphyrazine moiety (acceptor). These materials can be proposed to provide antenna effect to facilitate energy transfer and light harvesting.