Direct arylation polycondensation for the synthesis of bithiophene-based alternating copolymersElectronic supplementary information (ESI) available: Spectroscopic data. See DOI: 10.1039/c2py20917a

• Main Authors: Kuwabara, Junpei, Nohara, Yuta, Choi, Seong Jib, Fujinami, Yohei, Lu, Wei, Yoshimura, Ken, Oguma, Jun, Suenobu, Katsuhiro, Kanbara, Takaki
• Format: Article
• Language: English
• ISSN: 1759-9954; 1759-9962
• DOI: 10.1039/c2py20917a

Direct arylation polycondensation reactions using a simple catalytic system gave eight kinds of bithiophene-based alternating copolymers. The conditions for the reactions of 3,3′,4,4′-tetramethylbithiophene with dibromoarylenes were optimized to obtain high-molecular-weight polymers without formation of cross-linked structures. In the reaction of a dibromoarylene containing a reactive C-H bond, a short reaction time (1.5 h) was suitable for preventing side reactions. In contrast, a long reaction time (6 h) gave high-molecular-weight polymers from dibromoarylene monomers without a reactive C-H bond. This polycondensation reaction enables the synthesis of polymers containing dye structures such as diketopyrrolopyrrole and isoindigo, which are applicable as materials for polymer solar cells. Direct arylation polycondensation gave bithiophene-based conjugated polymers serving as materials for polymer solar cells.