Organocatalytic Synthesis of Oxazolines and Dihydrooxazines from Allyl‐Amides: Bypassing the Inherent Regioselectivity of the Cyclization

A selective and efficient methodology for the construction of either oxazolines or dihydrooxazines from the corresponding allyl‐amides is reported. Bypassing the inherent selectivity of the cyclization and depending on the substitution pattern of the substrate, a selective epoxidation‐cyclization was developed leading to either the five‐membered or the six‐membered ring, upon simple and complementary reaction conditions. The cyclization products were obtained in good to excellent yields and high selectivities.