Synthesis and Copper(I)‐Driven Disaggregation of a Zinc‐Complexed Phthalocyanine Bearing Four Lateral Coordinating Rings

Abstract

A new zinc phthalocyaninate, bearing four flexible phenanthroline‐containing 30‐membered rings was synthesized by template condensation of a macrocyclic phthalonitrile. The resulting phthalocyanine was an insoluble aggregate. However, in the presence of CuI ions, the formation of a soluble complex was observed. UV/Vis and DOSY NMR spectroscopic studies showed a monomolecular state for this species in solution. 1H‐1H ROESY demonstrated that the macrocyclic substituents adopt a folded conformation, giving the complex a globular shape. The folding originates from stacking interactions between the phthalocyanine core and peripheral copper(I)–phenanthroline complexes.

Modern Synthetic Approaches to Phthalonitriles with Special Emphasis on Transition-Metal Catalyzed Cyanation Reactions

“…[25] Performing this reaction exactly under reported conditions, namely, in air, in the presence of PMHS with portionwise addition of Zn(CN) 2 resulted in low conversion (~15 %) of 1a into 1b. However, when all reagents were mixed at a time, DMAA was added, mixture was flushed with argon and reaction was performed under inert atmosphere, dinitrile 1b was obtained in excellent yield of 85 %.…”

“…N,N-Dimethylformamide -DMF (Aldrich, ≥98.0 %) and N,N-dimethylacetamide -DMAA (Aldrich, ≥99 %) were used as received without further purification. 1,2-Dibromo-4,5-bis[2''-(2'-hydroxyethoxy)ethoxy]benzene 1a, 1,2-dicyano-4,5-bis[2''-(2'-hydroxyethoxy)ethoxy]benzene 1b, [25] 1,2-dibromo-4,5-bis[2''-(2'-benzyloxyethoxy)ethoxy]benzene 2a, [16] were synthesized as reported elsewhere. NMR spectra were recorded on Bruker Avance 600.…”

“…[25] Interest in dinitrile 1b arose previously since it is a promising precursor to phthalonitriles, bearing macrocyclic coordinating fragments. Dibromide 1a does not undergo cyanation under Rosenmund-Braun conditions because of the presence of free OH-groups, therefore, some alternative strategies were proposed to prepare 1b, however their implementation was also unsuccessful.…”

“…Figure 14. Pd-catalyzed synthesis of phthalonitriles, bearing unprotected and benzylated diethyleneglycol chains (yields 1b -85 % [25] and 2b -81 %).…”

Synthesis of an Octa‐tert‐butylphthalocyanine: A Low‐Aggregating and Photochemically Stable Photosensitizer

“…During the last century, several research groups discovered that such systems have a strong absorption in the 600–750 nm range and that they can be applied in many high‐technology areas such as transistors,2 liquid crystals,3 semiconductors,4 gas sensors,5 solar cells,6 catalysts,7 photodynamic therapy (PDT) agents,8 and others 9,10. However, unsubstituted PCs present limitations for use in some areas because of their tendency to undergo aggregation (π‐stacking interactions), which leads to low solubility in most known organic solvents and a reduction in their optical and redox properties 1.…”