Gold-Catalyzed intramolecular Cyclization of N-Propargylic β-Enaminones for the Synthesis of 1,4-Oxazepine Derivatives

An efficient and mild one-pot, gold-catalyzed intramolecular cyclization of N-propargylic beta-enaminones has been achieved for the generation of 1,4-oxazepine derivatives. This synthetic transformation tolerates a range of substituted N-propargylic beta-enaminones in moderate to good yields.