Department of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA.
Guangdong Key Laboratory of Chiral Molecule and Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, 510006, China.
Angew Chem Int Ed Engl. 2021 Jun 7;60(24):13394-13400. doi: 10.1002/anie.202101641. Epub 2021 May 6.
An unprecedented Ag -catalyzed efficient method for the coupling of imino ethers and enol diazoacetates through a [3+2]-cycloaddition/C-O bond cleavage/[1,5]-proton transfer cascade process is reported. The general class of imino ethers that includes oxazolines, benzoxazoles and benzimidates are applicable substrates for these reactions that provide direct access to fully substituted pyrroles with uniformly high chemo- and regioselectivity. High variability in substitution at the pyrrole 2-, 5- and N-positions characterizes this methodology that also presents an entry point for further pyrrole diversification via facile modification of resulting N-functional pyrroles.
本文报道了一种前所未有的 Ag 催化的高效方法，通过 [3+2]-环加成/C-O 键断裂/[1,5]-质子转移级联反应，将亚氨基醚和烯基重氮乙酸酯偶联。一般的亚氨基醚包括恶唑啉、苯并恶唑和苯并咪唑，它们都是这些反应的适用底物，可直接得到全取代的吡咯，具有均匀的高化学和区域选择性。该方法具有高度的取代多样性，可在吡咯的 2-、5-和 N-位进行取代，还可通过对生成的 N-官能化吡咯进行简单修饰，进一步拓展吡咯的多样性。
