The dynamic nature of noncovalent intermolecular interactions is essential for the development of functional supramolecular materials that exhibit specific properties in response to structural transformations. However, simultaneously achieving the quantitative switching of structural and fluorescence properties between discrete molecular assemblies based on an identical monomer in the solid state remains challenging. Herein, we report that anthracene‐based tetrasubstituted molecular tweezers undergo solid‐state self‐assembly to form either discrete cyclic hexamers or discrete cyclic tetramers. These assemblies exhibit a distinct fluorescence, i.e., blue for the cyclic hexamers and yellowish green for the cyclic tetramers, and their formation is precisely regulated by the electron density on the anthracene panels. Furthermore, upon exposure to solvent vapor, the cyclic tetramers undergo a reversible transformation into dimers accompanied by fluorescence changes in the solid state. This vapofluorochromic behavior demonstrates the potential of this system for the fluorescence sensing of various carbonyl‐ and sulfinyl‐containing compounds. Thus, this study represents the first investigation on the correlation between discrete solid‐state self‐assemblies and fluorescence properties using condition‐responsive anthracene‐based molecular tweezers.
Watanabe et al. (Wed,) studied this question.