Synthesis and electrochemical characterization of thiophenes with pendant fluorescent terpyridine

A novel series of thiophenes with terpyridine pendant groups were synthesized by Steglich esterification in the presence of DCC/DMAP and the synthesized monomers were electrochemically polymerized onto microelectrodes using glassy carbon and carbon fiber as active electrode materials. Each pendant group has aliphatic spacers with different chain lengths affecting the movement of the terpyridine groups. The synthesized thiophene derivatives were characterized by electrochemical and spectroscopic methods. The electrochemical impedance spectroscopic measurements of polythiophene-terpyridine (PTh-Terpy) derivatives were given comparatively. The fluorescence properties of the compounds were observed; all compounds were fluorescent, with higher fluorescence intensity for the shorter chain length, and slightly reduced fluorescence relative to that of the free terpyridine fluorophore. Morphological characterization was achieved via scanning electron microscopy.