Organic Chemistry Institute and Center for Soft Nanoscience, Westfälische Wilhelms-Universität Münster , Corrensstrasse 40, 48149 Münster, Germany.
Institute of Materials Physics, Westfälische Wilhelms-Universität Münster , Wilhelm-Klemm-Strasse 10, 48149 Münster, Germany.
J Am Chem Soc. 2016 Apr 6;138(13):4547-54. doi: 10.1021/jacs.6b00484. Epub 2016 Mar 22.
A simple and high yield synthesis of water-soluble arylazopyrazoles (AAPs) featuring superior photophysical properties is reported. The introduction of a carboxylic acid allows the diverse functionalization of AAPs. Based on structural modifications of the switching unit the photophysical properties of the AAPs could be tuned to obtain molecular switches with favorable photostationary states. Furthermore, AAPs form stable and light-responsive host-guest complexes with β-cyclodextrin (β-CD). Our most efficient AAP shows binding affinities comparable to azobenzenes, but more effective switching and higher thermal stability of the Z-isomer. As a proof-of-principle, we investigated two CD-based supramolecular systems, containing either cyclodextrin vesicles (CDVs) or cyclodextrin-functionalized gold nanoparticles (CDAuNPs), which revealed excellent reversible, light-responsive aggregation and dispersion behavior. To conclude, AAPs have great potential to be incorporated as molecular switches in highly demanding and multivalent photoresponsive systems.
报道了一种简单高产的水溶性偶氮吡唑(AAP)的合成方法,其具有优异的光物理性质。引入羧酸官能团可以实现 AAP 的多样化功能化。基于开关单元的结构修饰,可以调节 AAP 的光物理性质,从而获得具有有利光稳定态的分子开关。此外,AAP 与β-环糊精(β-CD)形成稳定且对光响应的主客体络合物。我们最有效的 AAP 显示出与偶氮苯相当的结合亲和力,但 Z-异构体的开关更有效,热稳定性更高。作为原理验证,我们研究了两种基于 CD 的超分子体系,分别包含环糊精囊泡(CDVs)或环糊精功能化的金纳米粒子(CDAuNPs),它们显示出优异的可逆、对光响应的聚集和分散行为。总之,AAP 具有作为高度要求和多价光响应系统中的分子开关的巨大潜力。