Synthesis and Photophysical Properties of Annulated Dinuclear and Trinuclear Phthalocyanines

Abstract

Metal-free mononuclear, dinuclear and trinuclear phthalocyanines were prepared by a mixed cyclotetramerisation of a 1,2,4,5-tetracyanobenzene derivative and 4,5-bis(2,6-dimethylphenoxy)phthalonitrile. For the first time, a pi-electron-conjugated trinuclear phthalocyanine was synthesised with phthalocyanine units connected by common annulated benzene rings. The Q band of the trinuclear compound in solution occurs at lambda = 944 nm whereas those of the dinuclear and mononuclear compounds are at lambda = 853/830 and 701/664 nm, respectively. Fluorescence quantum yields, fluorescence lifetimes and singlet-oxygen quantum yields of the compounds were determined.

New Approach to the Synthesis of Planar Binuclear Phthalocyanines of Mg, Zn and Rare Earth Elements

“…Methoxide-anions as a hard nucleophilic agent attack the carbon atom of nitrile group more effectively than analogous ion generated from high-boiling alcohols upon addition of the catalytic amount of organic bases, for instance, DBU (1,8-diazabicyclo[5.4.0]undec7ene) or during autoprotolysis (N,N-dimethylaminoethanol). Using the excess of CH 3 OLi provides a high concentration of methoxide-anions. So it is reasonable to assume that the rate of the nucleophilic attack increases in comparison with classic method, which implies nucleophile generation in catalytic amounts.…”

“…[1,2] Such compounds have the intensive absorption in the near IR region. [3,4] Thus, elaboration of the convenient and available approaches to this type of complexes is extremely actual.…”

Ionic Interactions between Charged Phthalocyanine and Fullerene Derivatives

“…4,5-Bis(2,6-dimethylphenoxy)phthalonitrile (5) [14] and 4,5-bis(3-pyridyloxy)phthalonitrile (4) [15] were synthesized as previously described. Symmetrically substituted phthalocyanines 1-3 were prepared as described before.…”

Singlet oxygen quantum yields and photostability of planar binuclear phthalocyanines

“…However, their stability is significantly reduced compared to Pcs. Another example of NIR-absorbing Pc analogs are bi-and trinuclear Pcs connected via shared benzene rings [16,17] with strong absorptions in the range of 850-950 nm without decreased stability.…”