Cu-Mediated Stereoselective [4+2] Annulation between N-Hydroxybenzimidoyl Cyanide and Norbornene.

A Cu-mediated stereoselective [4+2] annulation between N-hydroxybenzimidoyl cyanides and norbornene (NBE) has been developed for the synthesis of 4 H-1,2-oxazin-4-ones. The reaction proceeds through sequentially forming C-O/C-C bonds. The advantage of this reaction includes high stereoselectivity, excellent yields, as well as simple and mild reaction conditions. A total of 26 examples are presented along with some control experiments.