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Abstract 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.
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Approaches for improving the sustainability of conjugated polymer synthesis using direct arylation polymerization (DArP)
Direct arylation polymerization (DArP) provides a more sustainable alternative to conventional methods for conjugated polymer synthesis, such as Stille–Migita or Suzuki–Miyura polymerizations. DArP proceeds through a C–H activation pathway, allowing for a reduction in the synthetic steps needed to access the monomer, since the installation of a transmetallating reagent, such as an organostannane or organoboron, is not required. However, compared to small-molecule synthesis, the prevalent conditions employed for DArP still require hazardous or unsustainably sourced reaction components, such as the solvent and transition-metal catalyst. This mini-review highlights recent work on the implementation of sustainable solvents, transition metal catalysts, and overall polymerization methods for DArP. The extension of small-molecule direct arylation conditions towards polymer synthesis is also discussed, along with the associated challenges, mechanistic considerations, and outlook for future work.
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- Award ID(s):
- 1904650
- PAR ID:
- 10162619
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 11
- Issue:
- 3
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 630 to 640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9py01534e
