The synthesis, photophysical and electrochemical studies of symmetrical phthalocyanines linked thiophene substituents

Abstract

Tetrakis 4-(3-thienyl) and tetrakis 4-(5′-hexyl-2,2′-bithiophene) peripherally substituted zinc phthalocyanines were synthesized by using phthalonitrile derivatives. The phthalonitrile compounds were obtained through palladium catalyzed Suzuki–Miyaura cross-coupling reaction. The synthesized phthalocyanines were characterized by FT-IR, 1H NMR and MALDI-TOF-MS methods. The absorption and emission properties were studied by using UV–Vis absorption and photoluminescence spectroscopies. The electrochemical behaviors of compounds were also investigated using cyclic voltammetry (CV) measurements. The 5′-hexyl-2,2′-bithiophene substituent shifted the absorption band to red region and decreased the HOMO–LUMO energy gap of phthalocyanines.