Synthesis, Separation and Characterization of the Structural Isomers of Octa‐tert‐Butylphthalocyanines and Dienophilic Phthalocyanine Derivatives

Octa‐tert‐butylphthalocyanina‐tonickel(II) (4) was synthesized from 3,5‐di‐tert‐butylphthalonitrile (1) and nickel acetate. A nonstatistical mixture of the four structural isomers 4a–d was obtained. The isolation of the structural isomers 4a–d by preparative HPLC (MPLC) allowed their unequivocal identification and characterization by spectroscopic techniques. Moreover, a new family of tert‐butyl‐substituted phthalocya‐nines 6–10 containing dienophilic functionalities were prepared by condensation of 3,5‐di‐tert‐butylphthalonitrile (1) with 6,7–dicyano‐1,4‐epoxy‐1,4‐dihydronaphthalene (5). The separation of the phthalocyanines 6–10 and of some of their structural isomers was accomplished by normal column chromatography. The structural isomers were characterized by spectroscopic methods in terms of their symmetry.