Self-assembly of trinitrofluorenone derivatives with tetrasubstituted zinc phthalocyanines
The synthesis and characterization of two novel tetrasubstituted zinc phthalocyanines bearing bulky alkylaryloxy substituents in the so-called peripheral (1) and non-peripheral (2) positions is reported. Due to the presence of these bulky substituents, the non-peripheral substituted ZnPc 2 can be isolated as a pure regioisomer just by column chromatography. This is the first case where an α,α,α,α-tetrasubstituted regioisomer is isolated by column chromatography. Moreover, we describe the supramolecular complexation of both Pcs with the new pyridine-substituted trinitrofluorenone derivative TNFPy (3), whose synthesis and characterization is also commented. 1 H NMR titration experiments show that the system 2/3 presents a binding constant 35 times higher than system 1/3, which suggests a better accessibility to the metallic center.