Selective metal sensor phthalocyanines bearing non-peripheral functionalities: Synthesis, spectroscopy, electrochemistry and spectroelectrochemistry

A novel alcohol-soluble ionophore ligand and its non-peripherally tetrasubstituted functional 1,8,15,22-tetrakis(6-hydroxyhexylsulfanyl) metallophthalocyanines M[Pc(α-SC6H12OH)4] (M = Cu(II), Zn(II), Co(II); Pc = phthalocyanine) are reported. The aggregation and cation binding behaviors of the phthalocyanine compounds in the presence of soft AgI and PdII metal ions were investigated by using UV–Vis spectroscopy. The new compounds have been characterized by elemental analysis, IR, 1H, 13C NMR, UV/Vis spectroscopy, ESI and MALDI–TOF–MS mass spectra. Voltammetric and in-situ spectroelectrochemical studies show that while copper and zinc phthalocyanine complexes give well-defined ring-based reduction and oxidation processes, the cobalt phthalocyanine gives both metal-based and ring-based redox processes which have reversible and diffusion controlled character.

Graphical abstractThe novel alcohol-soluble functional non-peripherally tetrasubstituted phthalocyanines, 1,8,15,22-tetrakis(6-hydroxyhexylthio)-phthalocyanines, M[Pc(α-SC6H13OH)4] (M=Cu(II), Zn(II), Co(II)) are reported and characterized by elemental analysis, FT-IR, 1H NMR, UV/Vis. MS (MALDI-TOF), electrochemistry, and spectroelectrochemistry. The aggregation and cation binding behaviours of the phthalocyanine compounds in the presence of soft AgI and PdII metal ions was investigated by using UV–vis spectroscopy.Figure optionsDownload full-size imageDownload as PowerPoint slide