Crown-substituted naphthalocyanines: synthesis and supramolecular control over aggregation and photophysical properties

Abstract

Aggregation and photophysics of crown-substituted naphthalocyanines can be controlled by reversible cation-induced supramolecular assembling.

Cation-Induced Dimerization of Crown-Substituted Gallium Phthalocyanine by Complexing with Alkali Metals: The Crucial Role of a Central Metal

“…The unique properties of phthalocyanines (Pcs) make them a versatile platform for the construction of supramolecular materials by means of self-assembly as well as by combination with other classes of compounds . In particular, Pcs bearing crown ether groups assembled by noncovalent interactions, such as cation–crown ether, metal–ligand, or π–π stacking, have been widely investigated for more than 30 years. − The biomimetic model of the dimeric “special pair”, liquid crystals, gas sensors and conductive supramolecular materials, cation recognition, , nonlinear-optical (NLO) materials − and molecular switches − based on supramolecular assemblies of the crown-substituted Pcs have been reported. Despite this, the first direct evidence of the formation of supramolecular ensembles of crown-substituted Pcs in the solid state was received only in 2018 .…”

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

“…Starting phthalonitriles (15C5)Pn [33] and (Bu) 2 Pn [34] as well as naphthalonitrile (15C5)Nn [18] were synthesized using previously reported procedures. BuO-substituted naphthalonitrile (BuO) 2 Nn was firstly synthesized using alkylation of 2,3-dibromo-6,7-dihydroxynaphthalene with n-BuBr and subsequent Pd-catalyzed cyanation (Scheme 1) similarly to the previously reported procedures.…”

“…It was previously shown that Mg(OPent) 2 , which acts both as a base and template, can be successfully used for the synthesis of magnesium tetra-15-crown-5-naphthalocyaninate from (15C5)Nn without formation of crown ether cleavage products. [18] We tested this protocol in the present study to synthesize crown-phthalocyanine from (15C5)Pn in the presence of magnesium pentoxide. Subsequent demetalation of resulting magnesium tetra-15-crown-5-phthalocyaninate with AcOH yielded target 15-crown-5-phthalocyanine in 66 % yield without any traces of crown ether ring opening side products.…”

“…(15C5)Pn, [33] (BuO) 2 Pn, [34] (15C5)Nn, [18] and 2,3-dibromo-6,7-dihydroxynaphthalene [35] were synthesized according to the previously reported procedures. DBU (Aldrich, 98 %) was distilled over CaH 2 in vacuum and stored under argon.…”

“…[10][11][12][13][14][15][16][17] In 2018 synthesis and characterization of first representatives of crown-substituted naphthalocyanines was reported. [18] The studies evidenced of high potential of supramolecular approach to control both aggregation and photophysics of crown-Ncs.…”