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Conjugated microporous polymers (CMPs) are porous organic materials that display (semi)conducting behavior due to their highly π-conjugated structures, making them promising next-generation materials for applications requiring both electrical conductivity and porosity. Currently, most CMPs and related porous aromatic frameworks (PAFs) are prepared using expensive transition metals (e.g., Pd), significantly increasing the costs associated with their synthesis. Lewis acid-mediated cyclotrimerization reactions of methyl ketones and nitriles represent promising and green alternative methods for CMP and PAF synthesis. Herein, we demonstrate that the generality of the solvent-free cyclotrimerization reactions is significantly improved by using ZnBr2 instead of ZnCl2 as the ionothermal medium. Specifically, we show that 1,4-diacetylbenzene (DAB), 4,4′-diacetylbiphenyl (DABP), 2,7-diacetylfluorene (DAF), 1,3,5-triacetylbenzene (TAB), tetrakis(4-acetylphenyl)methane (TAPM), and 1,4-dicyanobenzene (DCNB) can be polymerized in molten ZnBr2 to produce highly conjugated and microporous materials, as confirmed by 77 K N2 adsorption measurements, IR, and solid-state NMR. These findings support that ZnBr2 is an excellent Lewis acid mediator and medium for the ionothermal synthesis of porous organic materials.
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Rational design of bifunctional conjugated microporous polymers
Conjugated microporous polymers (CMPs) are an emerging class of porous organic polymers that combine -conjugated skeletons with permanent micropores. Since their first report in 2007, the enormous exploration of linkage types, building units, and synthetic methods for CMPs have facilitated their potential applications in various areas, from gas separations to energy storage. Owning to their unique construction, CMPs offer the opportunity for the precise design of conjugated skeletons and pore environment engineering, which allow the construction of functional porous materials at the molecular level. The capability to chemically alter CMPs to targeted applications allows for the fine adaptation of functionalities for the ever changing environments and necessities. Bifunctional CMPs are a branch of functionalized CMPs that have caught interest of researchers because of their inherent synergistic systems that can expand their applications and optimize their performance. This review attempts to discuss the rational design and synthesis for bifunctional CMPs and summarize their advanced applications. To conclude, our own perspective on the research prospect of this type of material is outlined.
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- PAR ID:
- 10279482
- Date Published:
- Journal Name:
- Nanoscale Advances
- ISSN:
- 2516-0230
- 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/D1NA00479D
