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The syntheses of a variety of substituted diaminomaleonitriles, with variable nitrogen substituents, were undertaken. Linstead macrocyclization of the resulting diaminomaleonitriles gave access to a wide range of functionalized porphyrazine-octaamines and hexamines and norphthalocyaninediamines. Conversion of these macrocycles into metallic derivatives and studies of their electronic absorption, solubility and electrochemistry are described. These flexible tetraazaporphyrins show potential in a range of applications including biomedical agents, novel charge–transfer complexes, chemical sensors, novel electronic materials and non-linear optics.

Co-macrocyclizations of 2,3-dipropylmaleonitrile and 2,3-di-(4-(methoxycarbonyl)phenyl)maleonitrile, respectively, with N , N ′-dibenzyl- N , N ′-di-(11-tetrahydropyranyloxy-3,6,9-trioxo-undecyl))maleonitrile and N , N , N ′, N ′-tetramethylmaleonitrile were used to prepare derivatives of the 4,5-diamino-porphyrazine systems including the zinc(II) complexes. Subsequent oxidation of the macrocycles with potassium permanganate gave the corresponding seco -porphyrazines. These were shown to be efficient sensitizers for the production of singlet oxygen ( Φ Δ =0.15–0.57) by the determination of their photophysical properties.