Synthesis and characterization of new soluble phthalocyanines containing macrocycle units

A soluble metal-free phthalocyanine 5 and its metal complexes (Zn, Ni, Co and Cu) 6, 7, 8 and 9 containing eight 16-membered tetrathiamonoaza macrocycles on peripheral substituent positions have been synthesized. The metal-free phthalocyanine 5 was synthesized from 4,5-bis{[2-(1,4,10,13-tetrathia-7-azacyclohexadecan-7-yl)ethyl]oxy}phthalonitrile 4. The metal complexes 6, 7 and 8 were prepared by a tetramerization reaction of the phthalonitrile derivative 4 with appropriate materials. Copper(II) phthalocyanine 9 was prepared by the reaction of 4,5-bis{[2-(1,4,10,13-tetrathia-7-azacyclohexadecan-7-yl)ethyl]oxy}-1,2-dibromobenzene 3 with excess CuCN and dry quinoline. Liquid–liquid extraction of several heavy metal ions such as Ag+, Hg2+, Pb2+, Cd2+, Cu2+ and Zn2+ with compound 5 was also tested using picrate as the anion of the ion pair. The extraction avidity of 5 for Ag+ was found to be highest in the liquid–liquid phase extraction experiments. The new compounds were characterized by a combination of elemental analysis, UV–Vis, FT-IR, NMR and mass spectral data.

Graphical abstractMetal-free and metallophthalocyanines containing eight 16-membered tetrathiamonoaza macrocycles on peripheral substituent positions have been synthesized from a phthalonitrile and the appropriate starting materials. Liquid–liquid extraction of several heavy metal ions such as Ag+, Hg2+, Pb2+, Cd2+, Cu2+ and Zn2+ with compound 5 was also tested. The new compounds have been characterized by physical and spectroscopic techniques.Figure optionsDownload full-size imageDownload as PowerPoint slide