Ag- and Au-catalyzed addition of alcohols to ynimides: β-regioselective carbonylation and production of oxazoles.

Metal-catalyzed reactions of ynimides with alcohols to afford β-ketoimides and oxazoles are demonstrated. The triple bond of ynamides is generally activated by mineral acids or metal salts to lead to the regioselective addition of nucleophiles at the α-C-atom, because of the inherent electronic bias. In contrast, the two neighboring carbonyl groups of ynimides decrease the electron density of the triple bond and the nucleophiles attack the carbonyl C-atom.