Zn(OTf)₂-Promoted Isocyanide-Based Three-Component Reaction: Direct Access to 2-Oxazolines and β-Amino Amides

An efficient one-pot reaction of propargylamides, isocyanides, and water catalyzed by zinc was developed for the rapid construction of 2-oxazolines with a wide functional group tolerance. The methylene-3-oxazoline was proven to play a vitally important role to start the tandem cascade transformation through unfunctionalized alkynes with sequential nucleophilic addition approaches of isocyanide and water. Notably, with a slight alteration of the reaction temperature and the addition of one molecule of water, various β-amino amide derivatives were synthesized in good to excellent yields.