The Study on the Synthesis and Properties of α- and β-tetra-substituted Phthalocyanines

In order to comparatively studythe properties of theαandβalkoxy-substituted phthalocyanines, these two series of tetra-substituted phthalocyanines were synthesized from corresponding 3-alkoxyphthalonitrile and 4-alkoxyphthalonitrile with metal salts. The effect of temperature on the synthesis of phthalonitrilewas studied, the results indicated that theα-substituted derivativeswere formed more easily than correspoindingβderivatives. Two condensation methods of phthalonitriles were investigated comparatively. An attemptwas made to correlate the different substituted positions with the spectral performance ofPc. The results shown thatthe differentsubstituted has little effecton the maximumabsorption wavelength. In the contrary, the solubility can be improved largely by the introduction of the bulk high brached substituents. The spectra data also demonstrated that the maximum absorbance of phthalocyanine with the substituted group located in theαposition had large red-shift than that in theβposition. The results showed that the alloxy-substituents in theαposition had larger pertubance on theπconjucted systemof phthalocyanine than inβposition. The relationship between their structure and other properties including solubility and thermal gravity losses were also presented and discussed.