Propargyl carboxylates react with 1,3-dicarbonyl compounds and electron-rich arenes in the presence of Au(I) catalysts to give enol carboxylates via alpha,beta-unsaturated Au(I) carbenes or Au(I)-coordinated allenes formed by 1,2- or 1,3-acyl migration, respectively.
Gold-catalyzed addition of carbon nucleophiles to propargyl carboxylates
Org. Lett. 2007, 9, 4021-4024.