Kinetics of the dark cis-trans isomerization of azobenzene and azopyridine derivatives in ethanol and chloroform solutions

The study aimed to investigate the kinetics of dark cis-trans relaxation for a series of azobenzene (Az, alko-Az) and azo pyridine (AzPy-o, AzPy-m, AzPy-p, alko-AzPy-o, alko-AzPy-m, alko-AzPy-p) compounds containing OH- or 6-hydroxyalkoxyl group. Azo pyridines possess nitrogen atoms in ortho, meta, or para position relative to the N=N bond. The studies showed the effect of nitrogen atom's presence in the dye's structure and their localization on the kinetics of dark cis-trans reaction and the possibility of azo-hydrazone formation by hydroxy-substituted chromophores.

The data set includes files:

• ¹H NMR in DMSO-d_6, CDCl₃ and Et-OD at room temperature. For selected compounds also at 60^oC.
• FTIR in KBr pallets.
• Thermal studies were evaluated by DSC and TGA (DTG and TG dates) measurements.
• Thermal cis-trans isomerization in chloroform and ethanol solvents at room temperature. Isomerization was evaluated by UV-Vis measurements.