Phenanthroline-fused unsymmetrical phthalocyanines chelating rhenium(I) tricarbonyl units: Synthesis, spectroscopy and electrochemical properties

Phenanthroline-fused unsymmetrical phthalocyanine (2-H) and its zinc complex (2-Zn) were treated with Re (CO)(5)Cl to give rhenium(I) tricarbonyl chloride chelates 1-H and 1-Zn respectively, which represent the first example of phthalocyanines with peripherally appended rhenium(I) complex units. The molecular structure of 1-Zn was determined by single crystal X-ray diffraction analysis. The electronic absorption, magnetic circular dichroism, and steady-state and time-resolved fluorescence spectra and the singlet oxygen (O-1(2)) generation efficiencies of 1-H and 1-Zn were measured and compared with those of phenanthroline-fused unsymmetrical phthalocyanines 2-H and 2-Zn, and the corresponding symmetrical phthalocyanines 3-H and 3-Zn as well. The electrochemical properties of 1-H and 1-Zn were also studied by cyclic voltammetry and compared with those of 2-H and 2-Zn. The effects of unsymmetrical phenanthroline fusing and rhenium(I) chelating on the photophysical and electrochemical behaviors of phthalocyanines were highlighted based on the above investigations.

Automated summary

The study successfully synthesized phthalocyanines with peripherally appended rhenium(I) complex units and investigated their photophysical and electrochemical properties through a series of experiments, highlighting the effects of unsymmetrical phenanthroline fusing and rhenium(I) chelating on their properties.