Heindl Andreas H, Wegner Hermann A
Institute of Organic Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany.
Center for Material Research (LaMa), Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany.
Beilstein J Org Chem. 2020 Jan 3;16:22-31. doi: 10.3762/bjoc.16.4. eCollection 2020.
Multistate switches allow to drastically increase the information storage capacity and complexity of smart materials. In this context, unsymmetrical 1,3,5-tris(arylazo)benzenes - 'starazos' - which merge three photoswitches on one benzene ring, were successfully prepared. Two different synthetic strategies, one based on Baeyer-Mills reactions and the other based on Pd-catalyzed coupling reactions of arylhydrazides and aryl halides, followed by oxidation, were investigated. The Pd-catalyzed route efficiently led to the target compounds, unsymmetrical tris(arylazo)benzenes. These triple switches were preliminarily characterized in terms of their isomerization behavior using UV-vis and H NMR spectroscopy. The efficient synthesis of this new class of unsymmetrical tris(arylazo)benzenes opened new avenues to novel multistate switching materials.
多态开关能够大幅提高智能材料的信息存储容量和复杂性。在此背景下，成功制备了不对称的1,3,5-三（芳基偶氮）苯——“星氮唑”，其在一个苯环上合并了三个光开关。研究了两种不同的合成策略，一种基于拜耳-米尔斯反应，另一种基于芳基酰肼与芳基卤化物的钯催化偶联反应，随后进行氧化反应。钯催化路线有效地得到了目标化合物——不对称三（芳基偶氮）苯。利用紫外-可见光谱和核磁共振氢谱对这些三重开关的异构化行为进行了初步表征。这类新型不对称三（芳基偶氮）苯的高效合成开辟了通往新型多态开关材料的新途径。
