Cf. Vannostrum et al., CRYSTAL-STRUCTURE AND SILVER ION COMPLEXATION OF A NOVEL PORPHYRAZINESUBSTITUTED WITH 4 DITHIACROWN ETHER RINGS, Recueil des travaux chimiques des Pays-Bas, 113(2), 1994, pp. 109-110
The synthesis of magnesium porphyrazines substituted with sulfur-conta
ining 15-crown-5 and 18-crown-6 macrocycles is reported as well as the
single crystal structure of the 18-crown-6 substituted porphyrazine;
the larger crown ether compound is shown to form dimers with Ag+ ions,
unlike the porphyrazine with the smaller crown ether rings.