Enantioselective Cascade Annulation of α‐Amino‐ynones and Enals Enabled by Gold and Oxidative NHC Relay Catalysis
Jianfeng Jiang, Xia Wang, Shengping Liu, Sichen Zhang, Binmiao Yang, Yu Zhao, Shenci Lu
Abstract
We report herein an unprecedented gold and oxidative NHC relay catalysis that enables highly enantioselective cascade annulation between readily available α-amino-ynones with enals. This method utilizes the in situ-generated pyrrolin-4-ones as a novel and versatile synthon, which engage with α,β-unsaturated acylazolium intermediates generated from enals by oxidative NHC catalysis to produce pyrrole-fused lactones in high yield and excellent enantioselectivity. Synthetic utility of the lactone products is also demonstrated by facile conversion to densely functionalized pyrroles and pyrrolin-4-ones in high yields with excellent stereopurity.
Topics & Concepts
AnnulationEnantioselective synthesisCatalysisChemistryCascadeYield (engineering)Oxidative phosphorylationCombinatorial chemistryRelayLactoneStereochemistryReactivity (psychology)Organic chemistryCascade reactionReaction conditionsOrganocatalysisStereoisomerismChemical synthesisOxidative additionN-Heterocyclic Carbenes in Organic and Inorganic ChemistryCatalytic Alkyne ReactionsCatalytic C–H Functionalization Methods