Synthesis of the First Nonmetalated Triazolephthalocyanine Derivatives

Abstract

The synthesis of nonmetalated triazolephtahlocyanines is described for the first time. These compounds have been prepared by both one-step and stepwise procedures. Their spectroscopic data reveal a nonaromatic cross-conjugated 18pi-electron structure in contrast to their aromatic metalated derivatives.

Triazoleporphyrazines: A New Class of Intrinsically Unsymmetrical Azaporphyrins

“…Thus, metal-free triazolephthalocyanines cannot be obtained in alcoholic solvents such as butanol or 2-ethoxyethanol, due to their tendency to be cleaved by nucleophilic attack on their iminic double bonds; [9,18] the use of other polar solvents such as butyronitrile is therefore necessary. [14] Furthermore, triazoleporphyrazine 5 can be synthesized directly from a pyrrolinediimine precursor in the absence of any metal-template or base, an unusual fact that contrasts with the standard synthetic procedure to obtain porphyrazines. [19] The metal complexes 7aϪc were each prepared by treatment of the free base 5 with the appropriate metal acetate in DMF at 100°C.…”

“…[13] Conversely, the introduction of other inner metals remains a difficult task, [9] and only very recently have we succeeded in the preparation of some metal-free derivatives. [14] However, their purification is even more arduous than that of the metallated compounds, and in some cases impracticable due to their lability in silica gel.…”

Synthesis, Structure Peculiarities and Acid-Basic Behaviour of Triazoleporphyrazines

“…The triazolephthalocyanines, structural analogues of phthalocyanine, have been extensively studied by the group of Prof. Torres. [16][17][18][19] In particular, it has been shown that these compounds have permanent dipole moments and, hence, ability to form wellordered Langmuir-Blodgett monolayers [20] and to produce the second harmonic generation [21] as well. Recently the first representatives of a new class of noncentrosymmetric tetrapyrrole macrocycles -triazoleporphyrazines, have been synthesized.…”

Synthesis of proton-ionizable acyclic, macrocyclic and macrobicyclic compounds containing one or two triazole groups

“…Also, Bradshaw and coworkers have reported a series of diaza-18-crown-6 compounds with pendant phenol and hydroxyquinoline units [7]. Macrocycles with 4-hydroxypyridine [8-13] and triazole [13][14][15][16][17] heterocyclic subunits within the macroring have been developed by Brandshaw, Izatt and their coworkers, de Mendoza and Torres and their coworkers [18][19][20][21][22][23][24][25] and others [26][27][28]. Podands [23][24][25][26][27][28][29] and polyaza macrobicyclic cryptands [24] with triazole subunits have been prepared, as well.…”

“…Podands [23][24][25][26][27][28][29] and polyaza macrobicyclic cryptands [24] with triazole subunits have been prepared, as well. Macrocycles with a single triazole unit in the macroring exhibit complexation selectivity with univalent metal ions, such as Ag + [30]; whereas macrocycles with two such triazole units form strong complexes with divalent metal ions [21,25]. Chiral dialkyl-substituted triazole-18-crown-6 ligands have been used for enantiomeric recognition of organic ammonium salts [31].…”