Tetra-2,3-pyrazinoporphyrazines with peripherally appended pyridine rings. 20. Mono- and pentanuclear AlIII and GaIII complexes: synthesis and physicochemical and photoactivity studies
The autocyclotetramerization of the precursor 2,3-dicyano-5,6-di(2′-pyridyl)pyrazine [(CN)2Py2Pyz] in the presence of MCl3 compounds (M = AlIII, GaIII) leads to the formation of the new mononuclear porphyrazine complexes [Py8TPyzPzMCl]·xH2O (Py8TPyzPz = tetrakis-2,3-[5,6-di(2-pyridyl)pyrazino]porphyrazinato anion). From these species, the hydroxide analogues [Py8TPyzPzMOH]·xH2O were obtained by contact with hot water, and their corresponding pentanuclear species [(PdCl2)4Py8TPyzPzMCl]·xH2O could be easily formed by the reaction with PdCl2.