Multisubstituted Furan Formation from (Z)- or (E)-Enynyl Acetates: Tandem Reactions Accelerated by Electron-Donating Groups on Aromatic Rings

Multisubstituted furans were readily prepared from (Z)- or (E)-conjugated enynyl acetates with NXS under metal-free conditions at room temperature via the same haloallenyl ketone intermediates. This tandem haloallenyl ketone formation-furan formation reaction sequence was accelerated by electron-donating groups on the aromatic rings.