Azobenzene Macrocycles: Synthesis of a Z-Stable Azobenzenophane

Azobenzenes have attracted increasing attention in the past years due to their application as molecular switches. In this report, we present a macrocyclic bisazobenzene that exists as the stable Z-isomer. The synthetic efforts as well as the successful strategy are discussed. Final ring closure under continuous irradiation gave the (Z,Z)-bisazobenzenophane. This Z-azobenzene does not show any isomerization under either heating or prolonged irradiation. The thermal stability of the Z-form has also been supported by computations. The prepared bisazobenzenophane represents one of the few azobenzenes in which the Z-isomer is more stable than the E-isomer.

Photoelectrocatalytic Oxidation of Methyl Orange in KCI Solution

When potential was less than 1.2 V, electro-degradation rate was not more than 1.2% on both the films prepared using PEG or not. The film prepared with addition of PEG showed better degradation rates in the whole potential range than the film prepared without using of PEG. The highest degradation rates existed at 1.1 V of applied potential for both of the film electrodes, where degradation rate on film with PEG was 93.6% and the rate was 92.2% on the film without PEG. Methyl orange degradation rates increased with increasing KCl concentration from 0 to 0.7 mol/l, while degradation rates dropped down at even higher potential. Degradation rates increased with prolonged irradiation time for both of the two film electrodes.