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The twofold vinylogously enlarged porphyrin with a 22-rcelectron system 3 was prepared by vinylogous bisformylation of the dipyrrylmethane 7 to give 8 and subsequent acid-catalyzed condensation of 8 with 7. The [22]porphyrin 3 is characterized by a Soret band at 469 nm, which on protonation of the porphyrinoid becomes very narrow with the highest extinction coefficient so far observed for an organic pigment (E = 1090000). In the 'H-NMR spectrum 3 reveals a strong diamagnetic ring-current effect with a shift difference between inner and outer protons of A6 = 20.1 ppm, thereby proving itself a pronounced aromatic system.

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Catalysts based on samples of ZSM-5, differing in Si/Al ratio were applied in the Fries rearrangement of phenyl acetate. Experiments were carried out in batch reactors at 180 °C and continuously at various temperatures both in liquid phase and gas phase. A reaction scheme is proposed.