Post-macrocyclization strategy to octaphenoxy-substituted zinc pyrazinoporphyrazine, its photochemical and electrochemical properties

Abstract

An efficient post-macrocyclization strategy to new octaphenoxy-substituted zinc pyrazinoporphyrazine has been developed. This approach allows avoiding the template synthesis of the target compound from the phenoxy-substituted dinitrile, during which oligomerization and phenol release occur. The possibility of obtaining the initial octachloropyrazinoporphyrazine using template synthesis activated thermally and using microwave irradiation has been shown. Octaphenoxy-substituted zinc pyrazinoporphyrazine demonstrates short but intense triplet signals in triplet absorption spectrum and substantial singlet oxygen quantum yield (ΦΔ = 0.34). The fluorescent properties and fluorescence decay kinetics of target porphyrazines were studied. In contrast to the initial poorly soluble chlorinated complex, cyclic voltammetric measurements show both reduction and oxidation processes. Two waves of reduction and one wave of oxidation were observed. The electron-donating nature of phenoxy groups compared to chlorine groups is shown.