Acetal[6]Arenes: Rigid Chirality‐on‐Annulus Macrocycles Promoting Charge‐Transfer Co‐Assembly With Exceptional (Chiro)Optical Properties

) even exceed intrinsic Ac[6] values, indicating highly efficient chiral transfer. Ac[6] shows robust guest-capture capability, forming CT complexes not only via solution co-crystallization but also through simple physical mixing and even gas-phase guest uptake. By exploiting time-dependent capture kinetics and multicolor optoelectronic properties, we developed applications for optical sensing and time-encoded encryption. These results establish macrocyclization of rigid chirality-on-annulus units as a powerful strategy for creating functional supramolecular CT materials with emergent chiroptical and optoelectronic properties.