In the past decade, direct arylation polymerization (DArP) has rapidly developed as a sustainable synthetic protocol for cost‐effective, atom‐economical preparation of conjugated polymers. By circumventing monomer functionalization with toxic transmetallating reagents such as organostannane and organoboron required for Stille‐Migita and Suzuki‐Miyaura polymerization methods, DArP proceeds through a metal‐catalyzed CH activation pathway for the preparation of high‐performance conjugated polymer materials. This review evaluates the development of several classes of efficient catalysts/catalytic systems from small‐molecule studies to polymerizations, including the mechanisms involved in these transformations and how they inspire catalyst and monomer design for defect‐free conjugated polymer synthesis. Recent advances in developing more sustainable first‐row transition metal catalysts for DArP are also highlighted, and the fundamental understanding of these efficient and sustainable catalysts should motivate the pursuit for the next generation of catalytic design to enable more effective and environmentally friendly conjugated polymer synthesis.
Despite the emergence of direct arylation polymerization (DArP) as an alternative method to traditional cross‐coupling routes like Stille polymerization, the exploration of DArP polymers in practical applications like polymer solar cells (PSCs) is limited. DArP polymers tend to have a reputation for being marginally inferior to Stille counterparts due to the increased presence of defects that result from unwanted side reactions in direct arylation, such as unselective C‐H bond activation and homocoupling. We report ten DArP protocols across the three major classes of DArP to generate poly[(2,5‐bis(2‐hexyldecyloxy)phenylene)‐alt‐(4,7‐di(thiophen‐2‐yl)benzo[c][1,2,5]thiadiazole)] (PPDTBT). Through evaluation of the method and resulting photophysical and electronic properties, we show not all DArP methods are suitable for generating device‐quality alternating copolymers. When DArP PPDTBT was synthesized in superheated THF with Cs2CO3, neodecanoic acid, and P(
- NSF-PAR ID:
- 10239184
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science Part A: Polymer Chemistry
- Volume:
- 54
- Issue:
- 18
- ISSN:
- 0887-624X
- Format(s):
- Medium: X Size: p. 2907-2918
- Size(s):
- ["p. 2907-2918"]
- Sponsoring Org:
- National Science Foundation
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