Kerckhoffs Aidan, Christensen Kirsten E, Langton Matthew J
Chemistry Research Laboratory, Department of Chemistry, University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
Chem Sci. 2022 Sep 20;13(39):11551-11559. doi: 10.1039/d2sc04601f. eCollection 2022 Oct 12.
Molecular photoswitches operating in the red to near-IR region with controllable thermal relaxation rates are attractive components for photo-regulating biological processes. Herein, we report the synthesis of red-shifted azobenzenes functionalised with the heavier chalcogens and halogens that meet these requirements for biological application; namely fatigue-resistant photo-switching with red and near IR light and functional handles for further functionalisation for application. We report robust periodic trends for the chalcogen and halogen azobenzene series, and exploit intramolecular chalcogen bonding to tune and redshift the absorption maxima, supported by photo-physical measurements and solid-state structural analysis. Remarkably, the rate of the → thermal isomerisation can be tuned over timescales spanning 10 s by judicious choice of chalcogen and halogen substituents.
在红到近红外区域工作且具有可控热弛豫速率的分子光开关是用于光调节生物过程的有吸引力的组件。在此，我们报告了用较重的硫族元素和卤素官能化的红移偶氮苯的合成，这些偶氮苯满足生物应用的这些要求；即对红光和近红外光具有抗疲劳光开关特性以及用于进一步功能化应用的官能团。我们报告了硫族元素和卤素偶氮苯系列的稳健周期性趋势，并利用分子内硫族元素键合来调节和红移吸收最大值，这得到了光物理测量和固态结构分析的支持。值得注意的是，通过明智地选择硫族元素和卤素取代基，可以在跨越10秒的时间尺度上调节 → 热异构化的速率。
