Tuning properties of functionalized azobenzene photoswitches through variation of substitution and their position.

This perspective article features the recent work published in this journal on functionalized azobenzene photoswitches, studied by Venkataramani and coworkers [Grewal, S. et al (2024) Photochem. Photobiol., 1-16]. Azobenzene-based photochromic molecules undergo reversible trans-to-cis isomerization under exposure to light. The reverse cis-to-trans isomerization also takes place under thermal conditions in the dark. The study explores how different functional groups at various positions affect the responses of these compounds to light, their thermal stabilities, the isomeric ratios in the photostationary states, and their supramolecular behavior. Results show varied thermal half-lives, influenced by the terminal groups and their positions. Aggregation studies reveal the formation of supramolecular architectures, from microcrystals to gels with these systems. Despite complexities with the large volume of work with 30 different compounds, the research provides insights into designing efficient photochromic supramolecular motifs.