Palladium-catalyzed concerted [4+1] cyclization of prop-2-yn-1-ones and isocyanides

A palladium-catalyzed [4+1] cycloaddition of prop-2-yn-1-ones with double isocyanides is developed herein. The transformation worked well to produce a series of 2-amino-4-cyanofurans with high efficiency and a broad reaction scope. Based on mechanism studies, it is believed that the palladium-catalyzed [4 + 1] imidoylative cycloaddition of prop-2-yn-1-ones was concerted. Treated with aryl amine and H2O, the [4 + 1] cycloaddition of prop-2-yn-1-ones with double isocyanides provided 2-amino-4-amidylpyrroles efficiently. (C) 2020 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

In this study, a palladium-catalyzed [4+1] cycloaddition reaction was developed for the synthesis of a series of 2-amino-4-cyanofurans and 2-amino-4-amidylpyrroles with high efficiency and broad reaction scope. Mechanism studies suggest that the palladium-catalyzed [4 + 1] imidoylative cycloaddition of prop-2-yn-1-ones was concerted. This work provides a potential strategy for the synthesis of valuable heterocyclic compounds.