Polymeric phthalocyanines and their precursors, 7. Synthesis and analytical characterization of polymers from 1,2,4,5‐benzenetetracarboxylic acid derivatives

Abstract

Abstract Structurally uniform polymeric phthalocyanines 5a – e , containing imido end groups, were synthesized by reaction of different derivatives of 1,2,4,5‐benzenetetracarboxylic acid, 2a – d , with metal salts, urea and a catalyst. 5a – e were converted into polymers 3 , 4 and 6 , containing anhydride, carboxylic acid and amido end groups, respectively. IR and UV/VIS spectroscopy were used as appropriate methods for describing end groups and structural uniformity. It could be shown that the octasubstituted phthalocyanines 7 – 10 and not the phthalocyanine 1 must be considered as the low‐molecular‐weight analogues. The number of phthalocyanine units in the polymers was found to be ⩾ 9. The determination of the real molecular weights is not possible, due to the low solubility of the polymers.