Synthesis and characterization of near-IR absorbing metal-free and zinc(II) phthalocyanines modified with aromatic azo groups

Abstract

Abstract: Metal-free and zınc(II) phthalocyanine complexes bearıng peripheral (E)-4'((2' hydroxynaphthalen-1-yl)diazenyl) units have been synthesized. Novel phthalonitrile derivative required for the preparation of phthalocyanine complexes was prepared by coupling 4- aminophthalonitrile and 2-naphthol. The structures of these new compounds were characterized by using elemental analyses, proton and carbon nuclear magnetic resonance, fourier transform infrared spectroscopy, ultraviolet—visible spectrophotometry, fluorescence spectrophotometry, and mass spectrometry. In the UV-Vis spectra broad absorption band appears for phthalocyanine complexes at around 450—500 nm resulting from the azo-group introduced onto the phthalocyanine ring. The photophysical properties of metal-free and zinc(II) phthalocyanines were studied in tetrahydrofuran.