Covalent Organic Frameworks and Cage Compounds: Design and Applications of Polymeric and Discrete Organic Scaffolds

Abstract

Porous organic materials are an emerging class of functional nanostructures with unprecedented properties. Dynamic covalent assembly of small organic building blocks under thermodynamic control is utilized for the intriguingly simple formation of complex molecular architectures in one-pot procedures. In this Review, we aim to analyze the basic design principles that govern the formation of either covalent organic frameworks as crystalline porous polymers or covalent organic cage compounds as shape-persistent molecular objects. Common synthetic procedures and characterization techniques will be discussed as well as more advanced strategies such as postsynthetic modification or self-sorting. When appropriate, comparisons are drawn between polymeric frameworks and discrete organic cages in terms of their underlying properties. Furthermore, we highlight the potential of these materials for applications ranging from gas storage to catalysis and organic electronics.

Recent Advances in Covalent Organic Frameworks for Catalysis

“…[36][37][38] In addition, room-temperature synthesis is also an important strategy, which mainly containing two approaches, mechanochemical( MC) grinding and solventm ethod at room temperature. [34,[44][45] Figure 2s ummaries the representational examples of boron, nitrogen, and silicon-containing COFs.F or the boron-containing COFs, organic units are linked by either boroxinel inkages or boronate esters linkages. Thus catalytic sites can be successfully incorporated into the organic skeleton or layer spacesw ithoutc ompromising the crystallinity of COFs, which also arousing great interesti nh eterogeneous catalysis.…”

Synthesis of C−C Bonded Two‐Dimensional Conjugated Covalent Organic Framework Films by Suzuki Polymerization on a Liquid–Liquid Interface

“…Since the discovery of graphene, [1] synthesis of free-standing 2D conjugated COF films [2] (to some extent, which can be termed as 2D conjugated polymer [3] )d irectly linked by C À C bonds has been highly desired in synthetic chemistry. [4] However,alack of basic and compatible reactions for their synthesis limits their further study.…”

Designed Synthesis of a 2D Porphyrin‐Based sp2Carbon‐Conjugated Covalent Organic Framework for Heterogeneous Photocatalysis

“…[1] Unlike traditional polymers,C OFs are capable of precisely organizing molecular species into two-or three-dimensional (2D or 3D) networks featuring structural periodicity and inherent porosity.S ince first reported by Yaghi and co-workers in 2005, [2] av ariety of COFs have been reported over the past decade and found interesting applications in molecular absorption and separation, [3] catalysis, [4] sensing, [5] optoelectronics, [6] energy storage, [7] and other things. [1] Unlike traditional polymers,C OFs are capable of precisely organizing molecular species into two-or three-dimensional (2D or 3D) networks featuring structural periodicity and inherent porosity.S ince first reported by Yaghi and co-workers in 2005, [2] av ariety of COFs have been reported over the past decade and found interesting applications in molecular absorption and separation, [3] catalysis, [4] sensing, [5] optoelectronics, [6] energy storage, [7] and other things.…”