Aromatic Nucleophilic Substitution as a Side Process in the Synthesis of Alkoxy- and Crown-Substituted (Na)phthalocyanines

Abstract

This work reports on systematic survey for cyclotetramerization of crown-and butoxy-substituted phthalo-and naphthalonitriles in pentanol induced by DBU and PentOLi. It was demonstrated that these substrates undergo undesired side process of nucleophilic aromatic substitution of RO-groups with PentO-anions in dinitrile molecules. It results in cleavage of crown ether rings and leads to formation of inseparable mixture of (na)phthalocyanines with different ratios of intact and cleaved macrocyclic substituents. Butoxy-substituted substrates are notably less sensitive to nucleophilic attack. Application of magnesium pentoxide both as a base and templating agent does not result in crown ether ring opening reactions and affords target compounds in high yields. The results of work can be used as guidelines for the choice of bases and template agents in the synthesis of (na)phthalocyanines functionalized with macrocyclic substituents.

Benzoannelated A3B-Phthalocyanines with Diethyleneglycol Substituents: Synthesis and Control of Aggregation

“…The use of magnesium as a template leads to increased yields compared to non-template reaction of cyclotetramerization. [15] The resulting mixture of magnesium complexes was demetalated with trifluoroacetic acid without isolation of individual compounds and the resulting mixture of ligands was separated by column chromatography on alumina followed by fine purification using size-exclusion chromatography.…”

Ion-Driven Self-Assembly of Lanthanide Bis-phthalocyaninates into Conductive Quasi-MOF Nanowires: an Approach toward Easily Recyclable Organic Electronics

“…Tetra-15-crown-5phthalocyanine H 2 L was synthesized using a previously reported procedure. 44 Chloroform was used as a solvent for the preparation of the ML 2 (M = Lu, Tb, Ce) solution with the concentration 0.01 mmol. Acetonitrile was used for the preparation of KBPh 4 solution with concentrations 13 and 1 mmol.…”

Surfactant-Assisted Lateral Self-Assembly of One-Dimensional Supramolecular Aggregates of Lutetium Double-Decker Phthalocyaninates

“…Tetra-15-crown-5-phthalocyanine H 2 L was synthesized using the previously reported procedure. [33] Chloroform was used as a solvent for the preparation of the LuL 2 solution (1•10 -5 M) and t-BA solution (1•10 -2 M). Acetonitrile was used for the preparation of KBPh 4 solution (1.3•10 -2 M).…”