Synthesis of Amide Enol Carbamates and Carbonates through Cu(OTf)-Catalyzed Reactions of Ynamides with -Butyl Carbamates/Carbonates.

A highly regioselective approach to access amide enol carbamates and carbonates -, -, and was developed through Cu(OTf)-catalyzed reactions of ynamides with -butyl carbamates and and -butyl carbonates . Moreover, this strategy was successfully applied to generate amide enol carbamates - and - from imides and with ynamides through an -Boc cleavage-addition ring-opening process. A range of substituents was amenable to this transformation, and the desired amide enol carbamates and carbonates were obtained in moderate to good yields.