Tripodal Heptazine Core-based C3-Symmetric Multi-azo(hetero)arenes: Photoswitching, Supramolecular Sol-gel Behavior, and Base Sensing Prospects.

Abstract

Electron-deficient heptazine-based molecular and polymeric materials are a fast-growing area of research with their exciting electronic and optical properties, finding potential applications in catalysis, optoelectronics, etc. However, the continuous thirst for the design of heptazine-core-based molecular systems has grown in interest in the search for a new class of materials. Herein, we have synthesized two heptazine core-based C3-symmetric tripodal molecular systems decorated with three azobenzene and phenylazo-3,5-dimethylisoxazole as photoswitchable units connected through -NH linker. The photoswitching characteristics and thermal half-lives of photoswitched states were studied using UV-Vis and NMR spectroscopy. In addition, for azobenzene derivative 1, intriguing properties such as reversible sonication-induced gelation and base sensing ability have been demonstrated and supported by computations.