A Facile Synthesis of New L‐Proline‐Based Trifluoromethyl Oxazole Derivatives Using Microwave Irradiation and Conventional Method

Cyclization reaction of l‐proline with trifluoroacetimidoyl chlorides has been developed as an efficient strategy for the synthesis of trifluoromethyl oxazole derivatives by two methods: (a) in the presence of K2CO3 as a base in acetonitrile at room temperature and (b) in the presence of K2CO3 as a base in acetonitrile using microwave irradiation, in one pot reaction. The microwave irradiation has been found to be the most efficient method. High yields and short reaction times were obtained for both electron‐releasing and electron‐withdrawing substituted N‐aryltrifluoroacetimidoyl chloride derivatives by microwave irradiation.