title: Synthesis and photochemical properties of oligo-ortho-azobenzenes.
abstract: Azobenzenes have attracted great interest in recent years because of their ability to change conformation upon irradiation. This property has been featured in several applications not only in organic chemistry but also in biology. Even though monoazobenzenes have been extensively studied and documented in the literature, only a few methods are available for the synthesis of oligo-ortho-azobenzenes. Also, their photochemical properties have not been reported so far. This study shows an efficient strategy for the preparation of oligo-ortho-azobenzenes and the investigation of their photochemical properties. It is demonstrated that the absorption spectra are highly influenced by the substituents. Interestingly, none of the ortho-bis-, tris-, or tetra-azobenzenes showed any E → Z isomerization. Only the ortho-nitrogen-substituted monoazobenzenes' photochromic behavior upon UV irradiation was observed.
authors: Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland.
authors: Silvia
authors: S
authors: Bellotto
authors: Raphael
authors: R
authors: Reuter
authors: Christian
authors: C
authors: Heinis
authors: Hermann A
authors: HA
authors: Wegner
mesh_terms: D001391:Azo Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D015394:Molecular Structure; D055668:Photochemical Processes; D013237:Stereoisomerism
chemical_list: D001391:Azo Compounds; C009850:azobenzene