Hu Weigao, Zhan Qiangqiang, Zhou Hongwei, Cao Shanshan, Jiang Zhiyong
International Scientific and Technological Cooperation Base of Chiral Chemistry, Henan University Kaifeng Henan 475004 P. R. China
College of Biological, Chemical Sciences and Engineering, Jiaxing University Jiaxing Zhejiang P. R. China 314001.
Chem Sci. 2021 Mar 29;12(19):6543-6550. doi: 10.1039/d1sc01470f.
Totally different functionalization and construction as two fundamental synthetic protocols have long been applied to furnish azaarene variants. Here, a novel radical-based functionalization-oriented construction strategy by exploiting the electronic properties of azaarenes and the high reactivity of radicals is developed. Under a photoredox catalysis platform, the robust ability of such an artful combination of functionalization with construction is disclosed in the synthesis of valuable 3-azaarene-substituted densely functionalized pyrroles. In addition to the ability to use the readily accessible feedstocks, the high synthetic efficiency and the good functional group tolerance, the substrate scope is broad (81 examples) resulting from the capability to flexibly replace the types of azaarenes and other substituents. Control experiments and density functional theory (DFT) calculations elucidate the plausible mechanism involving the reaction pathways and the important role of NaHPO as an additive in the reaction.
作为两种基本的合成方法，完全不同的官能团化和构建方法长期以来一直被用于制备氮杂芳烃变体。在此，通过利用氮杂芳烃的电子性质和自由基的高反应活性，开发了一种新型的基于自由基的官能团化导向构建策略。在光氧化还原催化平台下，这种巧妙结合官能团化与构建的强大能力在合成有价值的3-氮杂芳烃取代的高度官能团化吡咯中得以展现。除了能够使用容易获得的原料、具有高合成效率和良好的官能团耐受性外，由于能够灵活替换氮杂芳烃和其他取代基的类型，底物范围很广（81个例子）。对照实验和密度泛函理论（DFT）计算阐明了可能的机理，包括反应途径以及NaHPO作为添加剂在反应中的重要作用。
