An anthracene-containing crown ether: synthesis, host-guest properties and modulation of solid state luminescence.

Organic solid state vapochromic materials are of great significance for the development of supramolecular chemistry and materials science. Herein, we synthesize a crown ether derivative (An34C10) containing two anthracene units and construct new crown ether-based vapochromic host-guest co-crystals. Due to the presence of anthracene, An34C10 not only shows good fluorescence properties but also displays mechanochromism. Single crystal structural analysis, powder X-ray diffraction and differential scanning calorimetry experiments demonstrate that the transformation between different stacking modes of An34C10 is responsible for mechanochromism. In addition, An34C10 can complex with 1,2,4,5-tetracyanobenzene (TCNB) to form host-guest complex (An34C10@TCNB) co-crystals. Because organic solvent fuming alters charge-transfer interactions in An34C10@TCNB, the fluorescence of the co-crystals can be turned on and off by 4-methylpyridine and chloroform vapors, respectively, realizing selective detection with opposite emission outputs. Meanwhile, the stimuli-responsive properties of An34C10 and An34C10@TCNB possess good cycling performance. This work provides a new strategy for the construction of organic solid state luminescent materials.