( a 云南民族大学化学与环境学院 生物基材料绿色制备技术国家地方联合工程研究中心 昆明 650500)

A novel, efficient and practical route to the preparation of (Z)-N-vinyl five-membered cyclic N,O-acetal derivatives utilized by continuous flow technology has been developed. The tandem cyclization reaction uses Schiff base imine as an intermediate, followed by the addition of hydroxyl group to alkynyl ester under the action of alkali, undergoing a unique intramolecular rearrangement to synthesize acetal derivatives. The whole cascade cyclization process generates a new C-O bond and C-N bond. In addition, the application of continuous flow technology can accurately control the three-component reaction pathway compared with traditional batch reaction, which can inhibit the generation of by-products between two components and provide a series of structurally diverse nitrogen-and oxygen-containing heterocycles in short time with high yields (81%～90%).