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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]

Adenosine triphosphate is an important biological molecule that provides energy and substrate for various cellular biochemical processes,it's ubiquitous in our lives. In this work, a novel electrochemiluminescence (ECL) sensor composed of Ru(bpy)32+, 2‐[4‐(2‐hydroxyethyl)piperazin‐1‐yl] ethanesulfonic acid (HEPES) and adenosine 5'‐triphosphate disodium salt (ATP) was developed for the first time. In this ECL system, Ru(bpy)32+ was used as the luminophore, HEPES buffer was served as the co‐reactant, and ATP was added to the system to amplify the luminous signal to investigate the ECL behavior. Through fluorescence spectroscopy, ECL spectroscopy, and cyclic voltammetry (CV), it can be hypothesized that the possible ECL mechanism is that ATP acts as an advanced co‐reaction promoter to accelerate the oxidation of HEPES to HEPES+⋅, more HEPES⋅ can be generated, which then reacts with oxidized Ru(bpy)33+ to emit stronger ECL signals. Subsequently, the influence of the ATP concentrations and the CV scanning speed was investaged. Moreover, it was observed that I− could quench the ECL intensity, the linear relationship range of I− concentration is from 10−3 to 10−6 m, the limit of detection is 3.7×10−8 m (signal/noise=3), therefore, a new, highly sensitive, and selective ECL approach for I− detection was created. [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]

Precise adjustment of microstructure and handedness of chiral nanomaterials is important to regulate their properties and performance. Herein, helical 3‐aminophenol formaldehyde resin (APF) nanotubes and corresponding carbonaceous nanotubes with controllable handedness and optical activity were obtained via an external metal ion‐mediated supramolecular co‐templating method in an enantiomerically pure template system, in which an appropriate amount of Mn2+ (Co2+ or Ni2+) with moderate coordination abilities can reverse the spatial arrangement of the phenylglycine‐based amphiphilic template molecules through metal coordination. Different stacking modes of coordination complexes in disparate metal ion systems lead to diverse helical senses (diameter and pitch) of the obtained helical APF. In addition, this coordination mode of metal intervention can be applied to other amine‐based helical polymer synthesis systems, which paves the way for the design of high‐quality chiral nanomaterials with satisfactory physical parameters and properties. [ABSTRACT FROM AUTHOR]