Synthesis of a Series of 12-Membered Azobenzene Macrocycles and Tuning of the Half-Life of the Thermal Z- E Isomerization

Souvik Ghosh; Christoph Eschen; Nadi Eleya; Anne Staubitz

doi:10.1021/acs.joc.2c00549

Synthesis of a Series of 12-Membered Azobenzene Macrocycles and Tuning of the Half-Life of the Thermal Z- E Isomerization

J Org Chem. 2023 Mar 17;88(6):3372-3377. doi: 10.1021/acs.joc.2c00549. Epub 2022 Jun 30.

Authors

Souvik Ghosh^{1

2}, Christoph Eschen¹, Nadi Eleya^{1

2}, Anne Staubitz^{1

2}

Affiliations

¹ Institute for Organic and Analytical Chemistry, University of Bremen, Leobener Straße 7, 28359 Bremen, Germany.
² MAPEX Center for Materials and Processes, University of Bremen, Bibliotheksstraße 1, 28359 Bremen, Germany.

PMID: 35771676
DOI: 10.1021/acs.joc.2c00549

Abstract

Azobenzene macrocycles (AzMs) represent a class of azobenzene that are typically photoswitchable with good switching yields of E and Z isomers at certain photostationary states. Here, the synthesis and versatile functionalization of 12-membered AzMs is presented to obtain various meta- and para-aryl-substituted AzMs in high yields of 71-98%. At different positions in the periphery, these substituents significantly impact on the thermal half-lives of the less-stable Z isomers. Para-substitution leads to faster thermal relaxation than meta-substitution, and electron-donating groups lead to a faster relaxation than electron-withdrawing groups.