Silver-Catalyzed Dearomative [3+2] Spiroannulation of Aryl Oxamic Acids with Alkynes.

A silver-catalyzed dearomative decarboxylative [3+2] spiroannulation of aryl oxamic acids with alkynes is described. The reaction provides reliable access to a range of azaspiro[4,5]trienones in moderate yields in aqueous media. In addition, the reaction exhibits a broad substrate scope and good functional group compatibility. [ABSTRACT FROM AUTHOR]