Substituent effects in N-acetylated phenylazopyrazole photoswitches

Authors

Tovtik R, Marzin D, Weigel P, Crespi S, Simeth NA

Journal

Beilstein Journals of Organic Chemistry

Citation

Beilstein J Org Chem. 2025 Apr 25;21:830-838.

Abstract

Phenylazopyrazole photoswitches proved to be valuable structural motifs for various applications ranging from materials science to medicine. Despite their potential, their structural diversity is still limited and a larger pool of substitution patterns remains to be systematically investigated. This is paramount as electronic effects play a crucial role in the behavior of photoswitches and a deeper understanding enables their straightforward development for specific applications. In this work, we synthesized novel N-acylpyrazole-based photoswitches and conducted a comparative study with 33 phenylazopyrazoles, comparing their photoswitching properties and the impact of electronic effects. Using UV-vis and NMR spectroscopy, we discovered that simple acylation of the pyrazole moiety leads to increased quantum yields of isomerization, long Z-isomer life-times, good spectral separation, and high photostability.

DOI

10.3762/bjoc.21.66
 
Pubmed Link