London dispersion as important factor for the stabilization of (Z)-azobenzenes in the presence of hydrogen bonding.

ABSTRACT: The understanding and control of the light-induced isomerization of azobenzenes as one of the most important classes of molecular switches is crucial for the design of light-responsive materials using this entity. Herein, we present the stabilization of metastable (Z)-azobenzenes by London dispersion interactions, even in the presence of comparably stronger hydrogen bonds in various solvents. The Z→E isomerization rates of several N-substituted 4,4'-bis(4-aminobenzyl)azobenzenes were measured. An intramolecular stabilization was observed and explained by the interplay of intramolecular amide and carbamate hydrogen bonds as well as London dispersion interactions. Whereas in toluene, 1,4-dioxane and tert-butyl methyl ether the hydrogen bonds dominate, the v

SUBMITTER: Heindl AH 

PROVIDER: S-EPMC6009200 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature