Palladium-catalyzed decarboxylation of vinyloxazolidine-2,4-diones used in the divergent reaction with 2-alkynylphenols and 2-alkynylanilines†

Abstract

The in situ generated aza-π-allylpalladium species, formed via the palladium-catalyzed decarboxylation of vinyloxazolidine-2,4-diones, were successfully used for the divergent reaction with 2-alkynylphenols and 2-alkynylanilines. Using Pd₂(dba)₃·CHCl₃ as the catalyst and Cu(OTf)₂ as the additive, a range of 2,3-disubstituted benzofurans and indoles were obtained in moderate to excellent yields. However, when PPh₃ ligand was added, a series of γ-O/N-substituted α,β-unsaturated amides were obtained in acceptable yields. This reaction demonstrates that vinyloxazolidine-2,4-diones are capable of undergoing palladium-catalyzed decarboxylative allylic functionalization with carbon, oxygen, and nitrogen nucleophiles.