PH Tuning of Water-Soluble Arylazopyrazole Photoswitches.

ABSTRACT: Arylazopyrazoles are an emerging class of photoswitches with redshifted switching wavelength, high photostationary states, long thermal half-lives and facile synthetic access. Understanding pathways for a simple modulation of the thermal half-lives, while keeping other parameters of interest constant, is an important aspect for out-of-equilibrium systems design and applications. Here, it is demonstrated that the thermal half-life of a water-soluble PEG-tethered arylazo-bis(o-methylated)pyrazole (AAP) can be tuned by more than five orders of magnitude using simple pH adjustment, which is beyond the tunability of azobenzenes. The mechanism of thermal relaxation is investigated by thorough spectroscopic analyses and density functional theory (DFT) calculations. Finally, the concepts of a tuna

SUBMITTER: Ludwanowski S 

PROVIDER: S-EPMC7693175 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature