Desymmetric [3+3] Cyclization of p -Quinamines for the Synthesis of 1,2,4-Oxadiazines and Hydroquinoxalines.

General and efficient strategies for highly diastereoselective synthesis of divergent heterocyclic scaffolds through desymmetric [3+3] cycloaddition of p -quinamines with 1,3-dipole surrogates hydroximoyl halides and α-halohydroxamates have been developed. This synthetic protocol provided a variety of heterocyclic architectures containing 1,2,4-oxadiazine and hydroquinoxaline skeletons in good yields with a wide substrate scope.