Synthesis and electrochemical properties of a series of novel tetra(4-benzoyl)phenoxyphthalocyanine derivatives

A novel phthalocyanine, 2,9(10),16(17),23(24)-tetra(4-benzoyl)phenoxyphthalocyanine, and its complexes with Zn(II), Cu(II), Co(II), and Ni(II) have been synthesized and characterized by a combination of elemental analysis, IR, 1 H NMR, UV-vis spectroscopy and mass spectrometry. All of the materials are very soluble in common organic solvents such as dichloromethane, chloroform, tetrahydrofuran, N , N -dimethylformamide and dimethyl sulfoxide. The Q band wavelengths of the complexes decrease in the order: Zn > Cu > Ni > Co. Redox processes were observed at −1.06, −0.74, 0.51 and 0.98 V for the free phthalocyanine, at −0.72 and 1.04 V for the Co(II) complex, at −1.24, −0.77, −0.24, 0.61 and 0.91 V for the Cu(II) complex, and at −0.74 and 1.20 V for the Ni(II) complex. The cyclic voltammograms of the phthalocyanine ring of the four species are similar, with reduction and oxidation couples each involving a one-electron transfer process.