Luminescent rhenium(I) carbonyl complex with redox noninnocent ONS donor azo-phenol ligand: Synthesis, X-ray structure, photophysical properties and live cell imaging

摘要： Herein, we have synthesized a new fluorescent rhenium(I) carbonyl complex 1, bearing {Re(CO)3}+ core with ONS donor thioether containing azo-phenol redox noninnocent ligand. The distorted octahedral geometry of the complex is confirmed by single crystal X-ray diffraction method. Cyclic voltammogram in acetonitrile exhibits irreversible oxidation peak (Epa = 1.36 V) along with quasi-reversible reduction peak at E1/2 = -0.92 V (ΔE = 210 mV). The complex exhibits low energy emission band at 525 nm with high emission quantum yield (Φ = 0.115). Cytotoxicity of the complex is studied by MTT method with human breast cancer cell lines (MCF-7) and IC50 value is found to be 23.6 μM. In presence of the complex (10 μM) a bright green fluorescence image of MCF-7 cell lines is observed under fluorescence microscope.