瑞士巴塞尔大学Wenger, Oliver S.研究团队报道了笼逃逸控制光氧化还原反应速率和量子产率。相关研究成果于2024年3月18日发表在国际顶尖学术期刊《自然—化学》。

光氧化还原催化依赖于光诱导的电子转移，从而在溶剂笼中产生包括氧化供体和还原受体的自由基对。为了发生生产性的向前反应，氧化的供体和还原的受体必须在经历自发的反向电子转移之前从溶剂笼中逸出。

该文中，研究人员展示了笼逃逸在三个基准光催化反应中发挥的决定性作用，即好氧羟基化、还原脱溴和氮杂-亨利反应。使用钌（II）基和铬（III）基光催化剂，它们提供了固有的不同笼逃逸量子产率，研究人员确定了光氧化还原产物形成速率和笼逃逸量子产量之间的定量相关性。这些发现在很大程度上可以在Marcus电子转移理论的框架内合理化。

附：英文原文

Title: Cage escape governs photoredox reaction rates and quantum yields

Author: Wang, Cui, Li, Han, Brgin, Tobias H., Wenger, Oliver S.

Issue&Volume: 2024-03-18

Abstract: Photoredox catalysis relies on light-induced electron transfer leading to a radical pair comprising an oxidized donor and a reduced acceptor in a solvent cage. For productive onward reaction to occur, the oxidized donor and the reduced acceptor must escape from that solvent cage before they undergo spontaneous reverse electron transfer. Here we show the decisive role that cage escape plays in three benchmark photocatalytic reactions, namely, an aerobic hydroxylation, a reductive debromination and an aza-Henry reaction. Using ruthenium(II)- and chromium(III)-based photocatalysts, which provide inherently different cage escape quantum yields, we determined quantitative correlations between the rates of photoredox product formation and the cage escape quantum yields. These findings can be largely rationalized within the framework of Marcus theory for electron transfer.

DOI: 10.1038/s41557-024-01482-4

Source: https://www.nature.com/articles/s41557-024-01482-4