Synthesis of oxazolines through a Pd-catalyzed alkyne-enabled C[sbnd]N activation of oxazolidines

Abstract

Strategies that enable selective CN bond activation of tertiary amines provide one of the cornerstones of modern organic synthesis. Here we describe a palladium-catalyzed selective CN bond cleavage of N-propargyl 1,3-oxazolidines, providing an efficient approach to a diverse range of oxazolines in good to excellent yields. The reaction proceeds through a domino process of the alkyne-enabled 1,5-hydrogen transfer/CN bond activation. In this way, two kinds of oxazoline skeleton that tolerates a wide variety of functional groups were formed.