The facile synthesis and characterization of tetraimido-substituted zinc phthalocyanines

Peripherally tetraimido-substituted zinc phthalocyanines were synthesized by the reaction of tetraamino-substituted zinc phthalocyanine with maleic anhydride, phthalic anhydride and tetrachlorophthalic acid, respectively. The compounds were characterized by MS, 1H NMR, UV–vis, IR and elemental analysis, the results of which were consistent with the proposed structures. UV–vis spectra showed that the wavelengths of the Q bands followed the order: Q2c > Q2b > Q2a; the strengths of the Q bands varied inversely with temperature. The compounds were stable in acid but unstable in alkali.