Synthesis and Properties of an Unsymmetrical Triazole-Functionalized (Phthalocyaninato)zinc Complex

The synthesis of 5,6‐dicyano‐1H‐1,2,3‐benzotriazole (2) was significantly simplified and its overall yield was increased. This opens up the possibility for an extended use of 2 as a precursor for triazole‐functionalized phthalocyanines. One of them, the unsymmetrical {9,10,16,17,23,24‐hexakis(3,5‐di‐tert‐butylphenoxy)[1,2,3]triazolo[4,5‐b]phthalocyaninato}‐zinc (5) was prepared in a statistical condensation of 2 and 4,5‐bis(3,5‐di‐tert‐butylphenoxy)phthalonitrile (3) with subsequent separation by column chromatography. The triazole‐functionalized (phthalocyanine)zinc complex 5 shows interesting spectral properties in solutions depending on the chemical medium because of the reactions which are typical for the triazole fragment. These are acid ionization of NH, coordination to metal ions, N‐alkylation and N‐acylation, among others. Compound 5 was characterized in detail using UV/Vis, 1H and 13C NMR spectroscopy, mass spectrometry (MALDI‐TOF), and elemental analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)