Glaser Felix, Kerzig Christoph, Wenger Oliver S
Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland.
Angew Chem Int Ed Engl. 2020 Jun 22;59(26):10266-10284. doi: 10.1002/anie.201915762. Epub 2020 Apr 7.
The energy of visible photons and the accessible redox potentials of common photocatalysts set thermodynamic limits to photochemical reactions that can be driven by traditional visible-light irradiation. UV excitation can be damaging and induce side reactions, hence visible or even near-IR light is usually preferable. Thus, photochemistry currently faces two divergent challenges, namely the desire to perform ever more thermodynamically demanding reactions with increasingly lower photon energies. The pooling of two low-energy photons can address both challenges simultaneously, and whilst multi-photon spectroscopy is well established, synthetic photoredox chemistry has only recently started to exploit multi-photon processes on the preparative scale. Herein, we have a critical look at currently developed reactions and mechanistic concepts, discuss pertinent experimental methods, and provide an outlook into possible future developments of this rapidly emerging area.
可见光子的能量以及常见光催化剂可达到的氧化还原电位为传统可见光照射所能驱动的光化学反应设定了热力学极限。紫外线激发可能具有破坏性并引发副反应，因此可见光甚至近红外光通常更可取。因此，光化学目前面临两个不同的挑战，即希望以越来越低的光子能量进行热力学要求越来越高的反应。两个低能量光子的汇聚可以同时应对这两个挑战，虽然多光子光谱已经很成熟，但合成光氧化还原化学直到最近才开始在制备规模上利用多光子过程。在此，我们批判性地审视了目前已开发的反应和机理概念，讨论了相关的实验方法，并对这个迅速兴起的领域未来可能的发展进行了展望。
