One‐Pot Synthesis of 2‐Oxazolines from Ethyl α‐Cyanocinnamate Derivatives with N‐Bromoacetamide

An efficient method for the one-pot synthesis of 2-oxazolines from ethyl α-cyanocinnamate derivatives with N-bromoacetamide in the presence of K3PO4 has been developed. The reaction performed smoothly and cleanly to give 2-oxazolines in good to excellent yields (up to 98%) within 4.5 h in acetone at room temperature without protection of inert gases. A total of 13 examples have been investigated. A possible nucleophilic addition reaction mechanism is proposed.