以色列魏茨曼科学研究所Rafal Klajn研究团队报道了约束条件下下可见光敏化偶氮苯的去平衡。相关研究成果发表在2023年9月22日出版的《科学》。

偶氮苯从其稳定的E异构体到亚稳定的Z态的光异构化是这些分子大量应用的基础。然而，这种反应通常需要紫外线，从而限制了其适用性。

该研究中，研究人员介绍了通过约束敏化（DESC）进行的去平衡，这是一种超分子方法，通过使用所需颜色的光（包括红色）来诱导E-to-Z异构化。DESC依赖于大环主体和光敏剂的组合，它们共同作用，选择性地结合和敏化E-偶氮苯进行异构化。Z异构体对宿主缺乏强亲和力，并被排出宿主，然后宿主可以将额外的E-偶氮苯转化为Z态。

通过这种方式，宿主-光敏剂复合物将光子能量转换为非平衡光稳定态形式的化学能，包括无法通过直接光激发获得的光稳定态化学能。

附：英文原文

Title: Disequilibrating azobenzenes by visible-light sensitization under confinement

Author: Julius Gemen, Jonathan R. Church, Tero-Petri Ruoko, Nikita Durandin, Micha J. Biaek, Maren Weienfels, Moran Feller, Miri Kazes, Magdalena Odaybat, Veniamin A. Borin, Rishir Kalepu, Yael Diskin-Posner, Dan Oron, Matthew J. Fuchter, Arri Priimagi, Igor Schapiro, Rafal Klajn

Issue&Volume: 2023-09-22

Abstract: Photoisomerization of azobenzenes from their stable E isomer to the metastable Z state is the basis of numerous applications of these molecules. However, this reaction typically requires ultraviolet light, which limits applicability. In this study, we introduce disequilibration by sensitization under confinement (DESC), a supramolecular approach to induce the E-to-Z isomerization by using light of a desired color, including red. DESC relies on a combination of a macrocyclic host and a photosensitizer, which act together to selectively bind and sensitize E-azobenzenes for isomerization. The Z isomer lacks strong affinity for and is expelled from the host, which can then convert additional E-azobenzenes to the Z state. In this way, the host–photosensitizer complex converts photon energy into chemical energy in the form of out-of-equilibrium photostationary states, including ones that cannot be accessed through direct photoexcitation.

DOI: adh9059

Source: https://www.science.org/doi/10.1126/science.adh9059