Synthesis and EPR studies of a near infrared absorbing tetrakis(2-naphthoxy)vanadylphthalocyanine

Vanadylphthalocyanine with four naphthoxy pendant groups on the periphery was prepared by cyclotetramerization of 4-(2-naphthoxy)phthalonitrile. The new compound was characterized by elemental analyses, Mass, IR and UV–Vis spectral data. The electronic spectra exhibit an intense absorption peak at 703 nm indicating the C_4v symmetry of VOPc. VO²⁺ ion in this structure was studied using electron paramagnetic resonance (EPR) technique at room temperature. The covalent bonding parameter for VO²⁺ ion and Fermi contact term were calculated using the principal axis values of the g and hyperfine splitting obtained from powder EPR spectrum.