Propargylamine Synthesis by Copper-Catalyzed Oxidative Coupling of Alkynes and Tertiary Amine N-Oxides

An efficient method for synthesizing N,N-di-methylpropargylamines is described. The synthesis exploited the Cu(II)-catalyzed oxidative alkynylation reaction of tri-methylamine N-oxides with alkynes in the absence of external oxidant. Both aromatic and aliphatic allcynes were utilized to achieve the corresponding products in moderate to excellent yields. The reaction conditions tolerated ester, hydroxy, and aldehyde groups.