A rings-in-pores net: crown ether-based covalent organic frameworks for phase-transfer catalysis

Shen, Ji-Chuang; Jiang, Wei-Ling; Guo, Wu; Qi, Qiao-Yan; Ma, Deli; Lou, Xiaobing; Shen, Ming; Hu, Bingwen; Yang, Hai‐Bo; Zhao, Xin

doi:10.1039/c9cc07639e

Cited by 41 publications

(45 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Covalent organic frameworks (COFs) 15 , 16 , an emerging class of porous crystalline polymers with two- or three-dimensional (2D or 3D) structures, have gained increasing attention and found potentials in gas storage and separation 17 – 21 , optoelectronics 22 – 26 , heterogeneous catalysis 27 – 30 , sensor 31 – 34 , energy storage 35 – 38 , etc. In principle, COFs can also be used as the platform for efficient tuning of molecular switches in solid state, but more importantly, they can show enhanced stability in contrast to most MOFs, due to their robust covalent linkages in the framework.…”

Section: Introductionmentioning

confidence: 99%

Redox-triggered switching in three-dimensional covalent organic frameworks

Gao

Yin

et al. 2020

Nat Commun

View full text Add to dashboard Cite

The tuning of molecular switches in solid state toward stimuli-responsive materials has attracted more and more attention in recent years. Herein, we report a switchable three-dimensional covalent organic framework (3D COF), which can undergo a reversible transformation through a hydroquinone/quinone redox reaction while retaining the crystallinity and porosity. Our results clearly show that the switching process gradually happened through the COF framework, with an almost quantitative conversion yield. In addition, the redox-triggered transformation will form different functional groups on the pore surface and modify the shape of pore channel, which can result in tunable gas separation property. This study strongly demonstrates 3D COFs can provide robust platforms for efficient tuning of molecular switches in solid state. More importantly, switching of these moieties in 3D COFs can remarkably modify the internal pore environment, which will thus enable the resulting materials with interesting stimuli-responsive properties.

show abstract

Section: Introductionmentioning

confidence: 99%

Redox-triggered switching in three-dimensional covalent organic frameworks

Gao

Yin

et al. 2020

Nat Commun

View full text Add to dashboard Cite

show abstract

“…Some recent advances in achiral COF-based phase-transfer catalysis indicate that aqueous asymmetric catalysis promoted by HCCOF catalystss hould be viable. [18,42] Typically,C OFs are obtained as micro-or nanosized crystalline solids.T herefore, their handlinga nd processability are very difficult, which significantly limits their practical applicationsi n industry.Although some achiral COF-based self-supporting materials,s uch as membranes and aerogels, for catalysis have been reported very recently, [43] HCCOF-based materials of this type are still unprecedented. The shaping of HCCOFs,h owever, is extremelyi mportant to achieve cost-efficient, feasible, and easily popularized devices, and consequently,l arge-scale asymmetric catalysis.…”

Section: Perspectives and Challengesmentioning

confidence: 99%

“…Therefore, the synthesis of hydrophilic or phase‐transfer HCCOF catalysts is important and will lead to a variety of green chemical transformations. Some recent advances in achiral COF‐based phase‐transfer catalysis indicate that aqueous asymmetric catalysis promoted by HCCOF catalysts should be viable [18, 42] …”

Section: Perspectives and Challengesmentioning

confidence: 99%

Homochiral Covalent Organic Frameworks for Asymmetric Catalysis

Zou

et al. 2020

Chemistry A European J

View full text Add to dashboard Cite

Owing to their permanent porosity,h ighly ordered and extended structure, good chemical stability,a nd tunability,c ovalent organic frameworks (COFs) have emerged as a new type of organic materials that can offer various applications in different fields. Benefiting from the huge database of organic reactions, the required functionality of COFs can be readily achieved by modification of the correspondingo rganic functional groups on either polymerizable monomers or established COF frameworks. This striking feature allows homochiral covalent organic frameworks (HCCOFs) to be reasonably designed and synthesized, as well as their use as au nique platform to fabricate asymmetricc atalysts. This contribution provides an overview of new progress in HCCOF-based asymmetricc atalysis, including design, synthesis, and their application in asymmetric organic synthesis. Moreover, major challenges and developing trends in this field are also discussed. It is anticipatedt hat this review article will provide some new insights into HCCOFs for heterogeneousa symmetric catalysis and help to encourage further contributions in this young but promising field.

show abstract

“…It was speculated that the relatively low-specific surface areas of P5COMs were due to the pores of the P5COMs being blocked by pillar[5]arene frameworks to some extent. 8 From Barrett–Joyner–Halenda (BJH) investigation (Fig. S16e, ESI†), we found that the P5COMs were hierarchical micro-mesoporous with broad pore sizes, indicating a disordered connection inside the P5COMs.…”

mentioning

confidence: 96%