Investigations into Competitive Cycloaddition/Cyclization or Elimination from 1,1-Dimethyl-propargylcarbamates of Anilines

Abstract

The copper-catalyzed reaction of 1,1-dimethyl-O-propargyl aniline carbamates was studied and revealed the unexpected formation of oxazolidin-2-ones and alkylamines. An in-depth study of the reaction conditions showed that the formation of these products was highly dependent on the solvent, copper catalyst and aniline substituents. The reaction can be oriented towards oxazolidinones in pyridine and alkylamines in ethanol, whereas cycloaddition can be achieved in dry tetrahydrofuran.