A new terpyridine tethered polythiophene: electrosynthesis and characterisation

A novel polythiophene bearing a pendant terpyridine moiety has been synthesized by electrochemical polymerization of a new thiophene monomer, namely 4′-(2,2′:5′,2″-terthien-3′-ethynyl)-2,2′: 6′,2″-terpyridine (TAT). The insertion of a conjugated ethynyl spacer between the terthiophene and the terpyridine fragments provides for an effective extension of the delocalization of electrons within the structural unit and the polymer as a whole. The synthesis and characterization of the relevant monomer, the electrosynthesis of the corresponding polymer and its electrochemical, UV-visible spectroelectrochemical and IR characterization are described. Finally, a comparison between the electrochemical, spectroscopic, and spectroelectrochemical properties of PTAT and the analogue, saturated-spacer PTTT (TTT = 4′-[(2,2′:5′,2″-terthien-3′-yl) methoxy]-2,2′:6′,2″-terpyridine) polymer is discussed. © 2011 Wiley Periodicals, Inc.