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The diversification of chirality in covalent organic frameworks (COFs) holds immense promise for expanding their properties and functionality. Herein, we introduce an innovative approach for imparting helical chirality to COFs and fabricating a family of chiral COF nanotubes with mesoscopic helicity from entirely achiral building blocks for the first time. We present an effective 2,3‐diaminopyridine‐mediated supramolecular templating method, which facilitates the prefabrication of helical imine‐linked polymer nanotubes using unprecedented achiral symmetric monomers. Through meticulous optimization of crystallization conditions, these helical polymer nanotubes are adeptly converted into imine‐linked COF nanotubes boasting impressive surface areas, while well preserving their helical morphology and chiroptical properties. Furthermore, these helical imine‐linked polymers or COFs could be subtly transformed into corresponding more stable and functional helical β‐ketoenamine‐linked and hydrazone‐linked COF nanotubes with transferred circular dichroism via monomer exchange. Notably, despite the involvement of covalent bonding breakage and reorganization, these exchange processes overcome thermodynamic disadvantages, allowing mesoscopic helical chirality to be perfectly preserved. This research highlights the potential of mesoscopic helicity in conferring COFs with favourable chiral properties, providing novel insights into the development of multifunctional COFs in the field of chiral materials chemistry. [ABSTRACT FROM AUTHOR]

Designing artificial systems to mimic chiral superstructures and exploring how achiral molecules precisely modulate their chirality is crucial to understand the origin of homochirality in nature. Herein, the tunability nature of supramolecular chirality is subtly applied to fabricate robust chiral covalent polymers with controlled macroscopic helicity. When using conventional supramolecular transcription methods to prepare chiral poly(m‐phenylenediamine), simply introducing various small amounts of achiral diaminopyridines (DAPs) to copolymerize with m‐phenylenediamine (MPD) enables the resulting chiral copolymers with adjustable helical configurations and chiroptical activities in an enantiopure template system. The strong hydrogen bonds between DAPs and the template molecules ((S)/(R)‐PhgC16) proved to be the driving force for guiding the chiral polymerization mode of MPD. Impressively, the exquisite self‐sorting phenomenon is observed by tuning the stoichiometric ratio of DAP and (R)‐PhgC16, where the as‐prepared copolymers with opposite helicity can exist simultaneously to form a double network structure and their chiroptical activity can be well regulated. In addition, based on such a copolymerization strategy, a conceptual library of helical functional copolymers is built with editable polymer types including conducting polymers and designable amine‐aldehyde condensation‐based polymers. This copolymerization‐mediated synthetic strategy may facilitate the development of chiral polymers with controlled morphologies and dynamic compositions. [ABSTRACT FROM AUTHOR]

We have combined the molecular imprinting and the layer-by-layer assembly techniques to obtain molecularly imprint polymers (MIPs) for the electrochemical determination of p-nitrophenol ( p-NPh). Silica microspheres functionalized with thiol groups and gold nanoparticles (Au-NPs) were assembled on a gold electrode surface layer by layer. The electrode was then immersed into a solution of pyrrole and p-NPh (the template), and electropolymerization led to the creation of a polymer-modified surface. After the removal of the silica spheres and the template, electrochemical impedance spectroscopy and differential pulse voltammetry (DPV) were employed to characterize the surface. The results demonstrated the successful fabrication of macroporous MIPs embedded with Au-NPs on the gold electrode. The effects of monomer concentration and scan rate on the performance of the electrode were optimized. Excellent recognition capacity is found for p-NPh over chemically similar species. The DPV peak current is linearly related to concentration of p-NPh in the 0.1 μM to 1.4 mM range, with a 0.1 μM limit of detection (at S/N = 3). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]