The Synthesis of Some Phthalocyanines and Napthalocyanines Derived from Sterically Hindered Phenols

Abstract

Abstract:The synthesis of a number of phthalocyanines (Pcs) and naphthalocyanines (NPcs) bearing bulky substituents is described. Precursors are prepared by using a nucleophilic aromatic substitution reaction between a sterically hindered phenol and 4-nitrophthalonitrile, 3-nitrophthalonitrile or 6-fluoro-2,3-napthalonitrile. Thus, Pcs and NPcs derived from 2,6-diisopropylphenol, 3,5-di-tert-butylphenol and 2,6-diphenylphenol possess substituents that are forced by steric constraints to adopt a non-planar conformation which enhances the solubility of the macrocycle.In particular, the Pc derived from 2,6-ditert-butyl-4-methylphenol displays exceptional solubility and a reduced tendency to aggregate in solution. 2,6-Ditert-butylphenol reacts as a carbon nucleophile to produce biphenyl phthalonitrile precursors to Pcs containing redox-active phenolic substituents.

Synthesis of substituted phthalocyanines

“…We use here term "periphery" for all substituents on the benzene rings of the molecule. The substituents located at positions 1, 4, 8,11,15,18,22, and 25 of the phthalocyanine ring (α-positions, Figure 1) are named as α−substituents, while those located at positions 2, 3, 9, 10, 16, 17, 23, and 24 (β-positions, Figure 1) are regarded as β-substituents. Introduction of peripheral substituents can dramatically increase the solubility of the target phthalocyanine in water or common organic solvents and can be used for an accurate tuning of optical and redox properties of phthalocyanines designed for a specific high-tech application.…”

“…alkoxide promoted cyclotetramerization) lead to formation of the pure least sterically crowded isomer of 'C 4h ' symmetry (since it is metal-free phthalocyanine, the actual symmetry of this compound is C 2h ) in low yield (1%). 15 On the other hand, harsh reaction conditions and use of a template (e.g. transition-metal ions) result in formation of a mixture of all four possible positional isomers in significantly higher yields even in the cases when 3-substituted phthalic acids were used as the precursors.…”

Synthesis, Electrochemical and Photophysical Properties, and Electroluminescent Performance of the Octa‐ and Deca(aryl)[60]fullerene Derivatives

“…We therefore developed the synthesis of deca-adducts bearing two different aryl groups Ar 1 and Ar 2 (C 60 Ar 1 5 Ar 2 5 H 2 ), more specifically, Ar 1 ¼ Ph and Ar 2 ¼ tert-butylphenyl, because tert-butyl groups are often employed to enhance the solubility of the aromatic compounds. [7] We synthesized pentaphenyl-penta(tertbutylphenyl)[60]fullerenes through a two-step synthesis by means of a pyridine-mediated [3d] functionalization reaction (Scheme 1). Pentaphenyl[60]fullerene C 60 Ph 5 Me was obtained in high yield from [60]fullerene as previously reported, and then treated with a tert-butylphenylcopper reagent in the presence of pyridine.…”

Fused Perylene–Phthalocyanine Macrocycles: A New Family of NIR‐Dyes with Pronounced Basicity

“…For the synthesis of the free base phthalocyanine M = H 2 elemental lithium was used instead of a metal salt (Scheme 3 b) and the reaction sequence was completed by acidic workup. [17] All synthesized compounds were purified by column chromatography (silica/methylene chloride + methanol), where the desired main product eluted as a blue band with red fluorescence. The yields were in the range between 4 and 12 %.…”