Achieving In Situ Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests' exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests' exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials.