FeCl3/I2-catalyzed tandem aerobic oxidative annulation of α-aminoketone hydrochlorides with aldehydes: synthesis of substituted oxazoles

A facile and efficient method for the synthesis of oxazoles has been developed through FeCl₃/I₂-catalyzed tandem aerobic oxidative annulation of α-aminoketone hydrochlorides with aldehydes. The reaction employs commercially available α-aminoketone hydrochlorides and aldehydes as the starting materials, offering notable advantages including operational simplicity, one-pot synthesis, low cost, broad scope, and good functional group tolerance. The synthetic utility has been demonstrated by the syntheses of 33 examples of oxazoles in yields up to 92 %. Furthermore, the protocol was successfully applied to gram-scale synthesis and to the one-step synthesis of the natural product oxytrofalcatin C.