Triazine‐centered C 3 ‐symmetric azobenzene trimers were synthesized using complementary azo‐forming strategies, providing a versatile platform for multiresponsive molecular photoswitches. Relative to the isoelectronic benzonitrile monomer, incorporation of the triazine core induces an intrinsic bathochromic shift of the azobenzene absorption bands. The thiomethoxy‐substituted derivative exhibits negative photochromism, enabling efficient trans–cis photoisomerization with wavelengths up to 525 nm. Combined temperature‐dependent operando UV/vis spectroscopy and DFT calculations reveal thermal cis–trans isomerization kinetics consistent with a triplet‐assisted rotational pathway. Evaluation of transmission coefficients exposes pronounced solvent‐friction effects, demonstrating that substituent‐controlled solute–solvent coupling governs thermal half‐lives beyond barrier heights. In addition, the electron‐deficient triazine core enables anion binding that induces intramolecular charge‐transfer absorption and modulates thermal relaxation, introducing triazine‐centered azobenzenes as supramolecular multistimuli‐responsive photoswitches.
Ayadi et al. (Sun,) studied this question.