Synthesis of Substituted 2-Amino-1,3-oxazoles via Copper-Catalyzed Oxidative Cyclization of Enamines and N,N-Dialkyl Formamides.

A facile synthesis of 2-amino-1,3-oxazoles via CuI -catalyzed oxidative cyclization of enamines and N,N-dialkyl formamides has been developed. The reaction proceeds through an oxidative C-N bond formation, followed by an intramolecular C(sp2 )-H bond functionalization/C-O cyclization in one pot. This protocol provides direct access to useful 2-amino-1,3-oxazoles and features protecting-group-free nitrogen sources, readily available starting materials, a broad substrate scope and mild reaction conditions.