Synthesis and Spectroelectrochemistry of Dithieno(3,2-b:2',3'-d)pyrrole Derivatives

摘要

New π-conjugated polymers containing dithieno(3,2-b:2',3'-d)pyrrole (DTP) were successfully synthesized via electropolymerization. The effect of structural differences on the electrochemical and optoelectronic properties of the 4-[4H-dithieno(3,2-b:2',3'-d)pyrrol-4-yl]aniline (DTP–aryl–NH2), 10-[4H-dithiyeno(3,2-b:2',3'-d)pirol-4-il]dekan-1-amine (DTP–alkyl–NH_2), and 1,10-bis[4Hdithieno(3,2-b:2',3'-d)pyrrol-4-yl] decane (DTP–alkyl–DTP) were investigated. The corresponding polymers were characterized by cyclic voltammetry, NMR (~1H-NMR and ~(13)C-NMR), and ultraviolet–visible spectroscopy. Changes in the electronic nature of the functional groups led to variations in the electrochemical properties of the π-conjugated systems. The electroactive polymer films revealed redox couples and exhibited electrochromic behavior. The replacement of the DTP–alkyl–DTP unit with DTP–aryl–NH2 and DTP–alkyl–NH_2 resulted in a lower oxidation potential. Both the poly(10-(4H-Dithiyeno[3,2-b:2',3'-d]pirol-4-il)dekan-1-amin) (poly(DTP–alkyl–NH_2)) and poly(1,10-bis(4H-dithieno[3,2-b:2',3'-d]pyrrol-4-yl) decane) (poly(DTP–alkyl–DTP)) films showed multicolor electrochromism and also fast switching times (<1 s) in the visible and near infrared regions.