Журнал "Макрогетероциклы"

Elena V. Ovsyannikova,^a Nataliya F. Goldshleger,^b Nadezhda M. Kurochkina,^a Vladimir E. Baulin,^a,c Aslan Yu. Tsivadze,^a and Ninel M. Alpatova^a@

^aA.N.  Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 119991 Moscow, Russia

^bInstitute of Problems of Chemical Physics, Russian Academy of Sciences, 142432 Chernogolovka, Russia

^cInstitute of Physiologically Active Compounds, Russian Academy of Sciences, 142432 Chernogolovka, Russia

^@Corresponding author E-mail: alpatova@elchem.ac.ru

DOI: 10.6060/mhc2010.2-3.125

Self-organization of phthalocyanines (Pc) as a result of stacking interaction between aromatic rings provides, in particular, their rather low solubility which increases when alkyl, alkylaromatic and polar groups for organic and aqueous media, respectively, are introduced as substituents in macrocycles. The presence of crown ethers groups both enhances solubility of Pc and provides new properties for these macrocyclic compounds: the crown fragments annulated or introduced via oxygen bridges provide self-organization of the Pc molecules involving the guest cation, whose stability depends on the observation of the principle of geometrical conformity and multiplicity of interactions, namely, a growing number of reacting groups. Phthalocyanine molecules comprising eight crown containing substituents, octa-(benzo-15-crown-5)phthalocyanines, to the utmost meet these requirements. Electronic spectroscopy as the most informative method for studying the aggregation of crown-substituted phthalocyaninates of metals in solution was used to study: 1) the behavior of octa-(benzo-15-crown-5)phthalocyaninates of nickel (Nicr8Pc) and cobalt (Cocr8Pc) in mixed solvents and in polar media including water; 2) the formation of related composites on ITO and quartz by the layer by layer deposition method; 3) the embedding of Pc in the tetraalkylammonium bromide matrix. In such conditions crown containing Pc can form a number of structures, for example, ‘sandwich’ heteronuclear complexes if a complex forming cation is larger than the crown ether cavity. It has been shown that complex formation between crown fragments of Mcr₈Pc (M = Ni, Co) and cations (Na⁺, K⁺ and TBА⁺) provides such phthalocyanines with solubility in a polar organic medium, namely, propylene carbonate. It was suggested that the possibility of dissolution is due to the presence of both a great number of substituents and an oxygen bridge between a benzo-crown group and a phthalocyanine macrocycle. The presence of a spacer provides crown groups with mobility which makes it possible to obtain identical ‘stack’ structures of Pc involving К⁺ or ТБА⁺ cations. For inorganic polar solvent (water), the presence of K⁺ in solution results in the dissolution of Mcr₈Pc (M = Ni, Co) and the formation of stable charged forms of octa-crown-metallophthalocyaninates what allows them to be used in the development of composites consisted of ultra-thin layers of differently charged ions, K⁺/Mcr₈Pc- PSS⁻.

Keywords: Octa(benzo-15-crown-5)substituted phthalocyaninates of nickel and cobalt, dissolution, heteronuclear complexes, composites, layer by layer deposition (LbL), tetraalkylammonium salts.

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