Synthesis, characterization, fluorescence spectra and energy transfer properties of a novel unsymmetrical zinc phthalocyanine with peripherally coordinated Ru(II) complex

Abstract

Abstract A novel unsymmetrically substituted zinc (II) phthalocyanine was synthesized through a multistep reaction sequence starting first with cyclotetramerization of 4-(4-nitrophenoxy) phthalonitrile and 4-(hexylthio) phthalonitrile, then reduction of nitro group to amino functionality and then its condensation with 1,10-phenanthroline-4-carbaldehyde. Finally, a new multicomponent ZnPc-Ru(bpy) 2 (phen) system consisting of a zinc-phthalocyanine core linked through a nonconjugated bridge to ruthenium(II) bis(bipyridine) complex was synthesized using the reaction of the phthalocyanine bearing a 4-substituted-1,10-phenanthroline subunit and [Ru(bpy) 2 Cl 2 ]·2H 2 O. The new compounds have been characterized by elemental analysis, IR, 1 H-NMR, UV–vis and MALDI-TOF MS spectral data. Intramolecular electronic interactions in these dyads were studied by absorption, and emission spectroscopy. Upon photoexcitation, these dyads exhibit intramolecular energy transfer from the Ru(II) chromophore to the ZnPc moiety.