Synthesis and photophysical properties of metallophthalocyanines substituted with a benzofuran based fluoroprobe

The synthesis, characterization and photophysical properties of the tetra- {6-(-benzofuran-2-carboxylate)-hexylthio} substituted copper(II), cobalt(II), manganese(III) and zinc (II) phthalocyanines, {M[Pc(β-S(CH ₂) ₆OCOBz-Furan) ₄], which were derived from 6-(3,4-dicyanophenylthio)-hexyl-2-benzofuranate (BzF) (1-4) are reported for the first time. The new compounds have been synthesized and fully characterized by elemental analysis, FTIR, UV-vis, ¹H- and ¹³C NMR, MS (Maldi-TOF). In this work, we also report the effects of peripherally bound BzF substituent on the photophysical properties of metallo phthalocyanine derivatives. The effects of changing the central metal ions on quantum yield are discussed. It was found that the substitution of BzF groups on the framework of phthalocyanines diminished the fluorescence quantum yield of these complexes depending on paramagnetic behavior of central metal atoms. In addition, central metal atoms like Co and Cu also caused to decrease in quantum yield of phthalocyanine backbone.