近日，武汉大学易红及其研究组发现，线性配对电解实现苯并呋喃与乙烯基重氮化合物的氧化还原中性(3 + 2)环化。2024年10月31日，国际知名学术期刊《美国化学会杂志》发表了这一成果。

电合成已成为有机化学中一种多功能和可持续的工具，为在温和和环境友好的条件下构建复杂的分子结构提供了有效的途径。然而，传统的电化学方法主要依赖于阳极氧化或阴极还原，限制了它们实现单电极氧化还原中性转化的能力。

在这项工作中，课题组引入了一种线性配对电解策略，绕过了这些限制，使苯并呋喃与乙烯基重偶氮化合物的氧化还原中性(3 + 2)环化成为可能。该方法有利于形成苯并呋喃三环支架，在合成化学和医药领域具有重要的应用价值。

转化过程通过连续的阳极氧化和阴极还原进行，利用自由基阳离子途径提供具有高选择性的多环化合物。循环伏安法和原位电化学质谱法（EC-MS）彻底验证了这一过程的效率和机制，并得到理论计算的支持，揭示了氧化还原中性电化学转化的潜力。

附：英文原文

Title: Linear Paired Electrolysis Enables Redox-Neutral (3 + 2) Annulation of Benzofuran with Vinyldiazo Compounds

Author: Lei Nie, Jiayi Yang, Zhao Liu, Shibo Zhou, Suming Chen, Xiaotian Qi, Aiwen Lei, Hong Yi

Issue&Volume: October 31, 2024

Abstract: Electrosynthesis has emerged as a versatile and sustainable tool in organic chemistry, offering an efficient pathway for the construction of complex molecular architectures under mild and environmentally benign conditions. Traditional electrochemical approaches, however, predominantly rely on either anodic oxidation or cathodic reduction, limiting their capacity to achieve redox-neutral transformations using a single electrode. In this work, we introduce a linear paired electrolysis strategy that circumvents these limitations, enabling a redox-neutral (3 + 2) annulation of benzofuran with vinyldiazo compounds. This method facilitates the formation of benzofuran-fused tricyclic scaffolds, which are valuable in synthetic chemistry and medicinal applications. The transformation proceeds through sequential anodic oxidation and cathodic reduction, leveraging a radical cation pathway to deliver polycyclic compounds with high selectivity. The efficiency and mechanism of this process are thoroughly validated using cyclic voltammetry and in situ electrochemical mass spectrometry (EC-MS) and supported by theoretical calculations, shedding light on the potential of redox-neutral electrochemical transformations.

DOI: 10.1021/jacs.4c12925

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c12925