Visible Light-Catalyzed Cascade Radical Cyclization of <i>N</i>-Propargylindoles with Acyl Chlorides for the Synthesis of 2-Acyl-9<i>H</i>-pyrrolo[1,2-<i>a</i>]indoles
Yu Liu, Zan Chen, Qiaolin Wang, Pu Chen, Jun Xie, Biquan Xiong, Panliang Zhang, Kewen Tang
Abstract
A novel and convenient visible light-catalyzed tandem radical cyclization of N-propargylindoles with acyl chlorides for accessing 2-acyl-9H-pyrrolo[1,2-a]indoles is established. This transformation involves sequential addition of the acyl radical to the carbon–carbon triple bond, intramolecular cyclization with the 2-position of indole, and isomerization of the carbon–carbon double bond. The experimental results show that this reaction contains a radical pathway and a radical chain process is not the major pathway for the formation of products.
Topics & Concepts
CatalysisAcylationCascadeChemistryRadical cyclizationVisible spectrumMedicinal chemistryPhotochemistryOrganic chemistryPhysicsChromatographyOptoelectronicsRadical Photochemical ReactionsCatalytic C–H Functionalization MethodsOxidative Organic Chemistry Reactions