Synthesis, H- or J-type aggregations, electrochemistry and in situ spectroelectrochemistry of metal ion sensing lead(II) phthalocyanines

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• 作者：Armağ ; an Gü ; nsel ; Meryem N. Yaraş ; ir ; Mehmet K ; az ; Atı ; f Koca
• 关键词：Phthalocyanine ; Metal sensing ; Lead ; Aggregation ; Cyclic voltammetry ; Spectroelectrochemistry ; Demetallization
• 刊名：Polyhedron
• 出版年：2010
• 出版时间：7 December 2010
• 年：2010
• 卷：29
• 期：18
• 页码：3394-3404
• 全文大小：1757 K

文摘

We report, in this study, peripherally 3- and 4-substituted functionalized ionophore ligands (1–3) and their α- and β-tetra polyalcohol substituted lead(II) phthalocyanines M{Pc[S–CH(C₃H₇)(C₂H₅OH)]₄} (7, 9 and 11) and M{Pc[S–C₆H₁₂(OH)]₄} (8, 10 and 12) which are a mixture of different isomers. The complexes have been fully characterized by elemental analysis, FT-IR, ¹H NMR, ¹³C NMR, MS (MALDI-TOF) and UV–Vis spectral data. These complexes induced H-type (face-to-face fashion) or J-aggregate (edge-to-edge) dimers when titrated with AgNO₃ or Na₂PdCl₄ in a THF–MeOH solution. Cyclic and square wave voltammetry studies showed that the complexes gave three one-electron ligand-based reductions and two one-electron oxidation couples having diffusion controlled mass transfer character. Assignments of these redox couples were confirmed by spectroelectrochemical measurements. The observation of split Q bands, which are characteristic spectral behavior of metal-free phthalocyanines, indicates demetallization of the complexes during the spectroelectrochemical measurement under the applied potentials. The types of the substituents on the ring of the phthalocyanines affect the demetallization process of the complexes.