Precision Synthesis of Various Low‐Bandgap Donor–Acceptor Alternating Conjugated Polymers via Living Suzuki–Miyaura Catalyst‐Transfer Polymerization

• Published in: Angewandte Chemie International Edition Vol. 61; no. 31; pp. e202205828 - n/a
• Main Authors: Kim, Hwangseok, Lee, Jaeho, Kim, Taehyun, Cho, Minyoung, Choi, Tae‐Lim
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.08.2022
• Edition: International ed. in English
• Subjects: Block copolymers; Catalyst-Transfer Polymerization; Catalysts; Chemical synthesis; Conjugated Polymer; Copolymers; Donor–Acceptor Copolymers; Energy gap; Molecular orbitals; Molecular weight; Monomers; Organic Semiconductors; Polymerization; Polymers; Retirement; Suzuki–Miyaura Coupling; catalyst-transfer polymerization; Suzuki-Miyaura coupling; donor-acceptor copolymer; conjugated polymer; organic semiconductor
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202205828

Herein, we demonstrate that living Suzuki–Miyaura catalyst‐transfer polymerization (SCTP) using a RuPhos Pd G3 precatalyst is a versatile method for the precision synthesis of various donor–acceptor alternating conjugated polymers (DA ACPs). First, the living SCTP of biaryl monomers with combinations of both medium to strong A and D were optimized to produce DA ACPs with controlled number average molecular weight (Mn), narrow dispersity (Ð, 1.05–1.29), and high yield (>87 %). Moreover, its expansion to controlled polymerization (Mn=9.2–40.0 kg mol−1) of an A1‐D‐A2‐D quateraryl monomer containing diketopyrrolopyrrole (DPP; strong A) was successful. The living SCTP also enabled the efficient one‐pot synthesis of various diblock and triblock copolymers. Lastly, the DA ACPs showed tunable optical band gap (Egopt, from 1.29 to 1.77 eV) and highest occupied molecular orbital (HOMO) level (from −5.57 to −4.75 eV), while their block copolymers exhibited broad absorption ranges and promising visible light‐harvesting properties. Donor–acceptor alternating conjugated polymers with various electronic characteristics, including strong donor–strong acceptor, are synthesized via living Suzuki–Miyaura catalyst‐transfer polymerization in a controlled manner. The polymerization also works with a complex quateraryl monomer and allows for one‐pot di(tri)block copolymer synthesis. The resulting polymers have tunable optical and electrochemical properties based on the combination of building units.