Synthesis and photophysical properties of novel (trifluoromethyl) phenylethynyl-substituted metallophthalocyanines

The synthesis of symmetrically substituted novel metallophthalocyanines (M = Zn(II), Cu(II), Co(II)) bearing four 3,5-bis(trifluoromethyl)phenylethynyl moieties was achieved by following the well-known palladium-catalyzed cross-coupling methodology starting from the corresponding tetraiodo-substituted metal phthalocyanines. Alkynyl substituted phthalocyanines (Pc) are scarcely soluble in organic solvents; however, due to the presence of fluorine atoms at the periphery of the Pcs obtained, their solubilities in most of the organic solvents were enhanced. The structures of the newly synthesized molecules were proposed according to elemental analysis and ¹H NMR, ¹⁹F NMR, FT-IR, ESI-MS and UV-Vis spectral data. The aggregative properties of the novel compounds were investigated in different concentrations. General trends were described for fluorescence quantum yield and lifetime of novel zinc derivative in tetrahydrofuran. The fluorescence of the complex is quenched by 1,4-benzoquinone (BQ), and fluorescence quenching properties have been investigated.