Dithienylbenzodipyrrolidone: New Acceptor for Donor–Acceptor Low Band Gap Polymers

An analogue of DPP, dithienylbenzodipyrrolidone (DTBDPD), was successfully synthesized. Several D–A copolymers, with different electron donating capability donor unit (fluorene, difluorene, dithienosilole, and dithienopyrrole) and DTBDPD acceptor, were prepared by means of Suzuki and Stille coupling reaction. The optical and electrochemical properties were demonstrated through UV–vis–NIR absorption and cyclic voltammetry (CV). All polymers showed near-infrared or even infrared absorption and deeper LUMO levels, as low as −3.80 eV.