Novel peripherally tetra-substituted octacationic metal-free and metallophthalocyanines: Synthesis, spectroscopic characterization and aggregation behaviours

In this study, new 1,3-bis[3-(diethylamino)phenoxy]propan-2-ol 1 and phthalonitrile derivative 3 bearing 1,3-bis[3-(diethylamino)phenoxy]propan-2-ol substituent at peripheral position have been synthesized. The synthesis, characterization of the tetra-4-(2-[3-(diethylamino)phenoxy]-1-{[3-(diethylamino)phenoxy]methyl}ethoxy) substituted metal-free 4 and metallophthalocyanines 5, 6, 7, (MPcs, M = Ni, Co, Cu) are reported for the first time. These new metal-free and metallophthalocyanines 4–7 were converted into water soluble quaternized products by the reaction with methyl iodide 4a–7a. The metal-free phthalocyanine 4 was prepared from phthalonitrile derivative 3 in n-pentanol with a catalytic amount of 1,8-diazabicyclo[5.4.0]undec-7ene (DBU). Metallophthalocyanines 5–7 were prepared by cyclotetramerization of 3 with the corresponding metal salts (NiCl2, CoCl2, CuCl2) in n-pentanol with a catalytic amount of DBU. The aggregation behaviours of the phthalocyanine complexes were studied in different solvents and concentrations. The new compounds have been characterized by using UV–vis, IR, 1H NMR, 13C NMR, MS spectroscopic data and elemental analysis.

► Synthesis and characterization of metal-free and metallophthalocyanines.
► Synthesis and characterization of octacationic metal-free and metallophthalocyanines.
► Investigation of aggregation behaviours of metal-free and metallophthalocyanines in different solvents.