Deciphering Electronic Coupling in Pyrene‐Azoheteroarene Dyads for Fluorescence Modulation by Photoswitching

Molecularly engineered, tunable photoluminescent systems play a crucial role in accessing next‐generation smart materials and bioimaging probes. To gain tunability in the emission characteristics of those molecular materials, establishing structure‐property relationships is necessary. Toward this, a series of nine fluorophore‐photoswitch dyads with distinctly connected pyrene (as fluorophore) and arylazopyrazole and arylazoisoxazole derivatives (as photoswitches) were designed and synthesized. All the synthetic targets have been explored for their photoswitching properties, thermal relaxations of Z isomers, fluorescence characteristics, and emission modulation using spectroscopy, along with their aggregation behavior through microscopy. Herein, the significance of connectivity‐dependent electronic coupling between the fluorophore and the photoswitch, as well as its impact on their photophysical properties, is explored. Furthermore, the microscopic studies revealed intriguing supramolecular architectures largely controlled by the π‐surface of the pyrene moiety in conjunction with its connectivity and the substitution pattern of azoheteroarenes and their intermolecular interactions.