Wortman Alan K, Stephenson Corey R J
Willard Henry Dow Laboratory, Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
Chem. 2023 Sep 14;9(9):2390-2415. doi: 10.1016/j.chempr.2023.06.013. Epub 2023 Jul 18.
Recently, organic synthesis has seen a renaissance in radical chemistry due to the accessibility of mild methods for radical generation using visible light. While renewed interest in synthetic radical chemistry has been driven by the advent of photoredox catalysis, a resurgence of electron donor-acceptor (EDA) photochemistry has also led to many new radical transformations. Similar to photoredox catalysis, EDA photochemistry involves light-promoted single-electron transfer pathways. However, the mechanism of electron transfer in EDA systems is unique wherein the lifetimes of radical intermediates are often shorter due to competitive back-electron transfer. Distinguishing between EDA and photoredox mechanisms can be challenging since they can form identical products. In this perspective, we seek to provide insight on the mechanistic studies which can distinguish between EDA and photoredox manifolds. Additionally, we highlight some key challenges in EDA photochemistry and suggest future goals which could advance the synthetic potential of this field of research.
近年来，由于利用可见光产生自由基的温和方法易于实现，有机合成领域在自由基化学方面迎来了复兴。虽然光氧化还原催化的出现推动了对合成自由基化学的新兴趣，但电子供体-受体（EDA）光化学的复兴也带来了许多新的自由基转化反应。与光氧化还原催化类似，EDA光化学涉及光促进的单电子转移途径。然而，EDA体系中的电子转移机制独特，其中自由基中间体的寿命通常较短，这是由于竞争性的反向电子转移所致。区分EDA和光氧化还原机制可能具有挑战性，因为它们可以形成相同的产物。从这个角度出发，我们旨在深入探讨能够区分EDA和光氧化还原反应途径的机理研究。此外，我们强调了EDA光化学中的一些关键挑战，并提出了未来的目标，这些目标可能会推动该研究领域的合成潜力。
