Rustler Karin, Nitschke Philipp, Zahnbrecher Sophie, Zach Julia, Crespi Stefano, König Burkhard
Institut für Organische Chemie, Universität Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
J Org Chem. 2020 Mar 20;85(6):4079-4088. doi: 10.1021/acs.joc.9b03097. Epub 2020 Feb 26.
The desire to photocontrol molecular properties ranging from materials to pharmacology using light as an external trigger with high spatiotemporal resolution led to the development of a broad range of photochromic scaffolds. Among them, azobenzenes are synthetically well accessible and show excellent fatigue resistance. Their photochromic properties vary with the substitution pattern and for different heteroarenes. However, the photochromism of 3(5)-substituted-1-pryazoles has not yet been investigated, although this compound class offers interesting possibilities of metal ion coordination and hydrogen bond formation via its NH moiety. Herein, we present the results of an experimental and computational investigation of arylazo-3(5)-arylazo-1-pyrazoles. To elucidate their properties, solvent and substitution effects on their light absorption, thermal half-lives, photostationary states, fatigue, and quantum yields were determined.
利用光作为具有高时空分辨率的外部触发器来光控从材料到药理学等分子性质的需求，促使了多种光致变色支架的发展。其中，偶氮苯在合成上易于获得且具有出色的抗疲劳性。它们的光致变色性质随取代模式以及不同杂芳烃而变化。然而，尽管3(5)-取代-1-吡唑这类化合物通过其NH部分提供了有趣的金属离子配位和氢键形成可能性，但尚未对其光致变色进行研究。在此，我们展示了芳基偶氮-3(5)-芳基偶氮-1-吡唑的实验和计算研究结果。为阐明其性质，测定了溶剂和取代对其光吸收、热半衰期、光稳态、疲劳和量子产率的影响。
