Rhodium‐Catalyzed Cascade Reactions of Indoles with 4‐Hydroxy‐2‐Alkynoates for the Synthesis of Indole‐Fused Polyheterocycles
Xiaowei Wu, Pinyi Li, Yangbin Lu, Qiao Jin, Jingwei Zhao, Xiuwen Jia, Hangcheng Ni, Lichun Kong, Xiaoning Zhang, Fei Zhao
Abstract
Abstract Herein, an efficient and regioselective Rh(III)‐catalyzed [4+2] annulation/lactonization cascade of indoles with 4‐hydroxy‐2‐alkynoates at room temperature to access the furo[3′,4′:4,5]pyrimido[1,6‐ a ]indole‐1,5(3 H ,4 H )‐diones is described. This method features mild reaction conditions, operational simplicity, excellent regioselectivity, broad substrate scope with good functional group tolerance, and good to excellent yields. magnified image
Topics & Concepts
ChemistryRegioselectivityAnnulationIndole testCatalysisRhodiumCascadeSubstrate (aquarium)Combinatorial chemistryReaction conditionsFunctional groupOrganic chemistryStereochemistryMedicinal chemistryChromatographyPolymerGeologyOceanographyCatalytic C–H Functionalization MethodsCyclopropane Reaction MechanismsCatalytic Cross-Coupling Reactions