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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]

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]