Microwave Assisted, Cesium Carbonate Catalyzed Mild and Efficient Synthesis of Pyranochromenes

摘要

A mild and efficient domino protocol successfully developed for the synthesis of 3,4-dihydropyrano[c]chromenes from 4-hydroxy coumarin, malononitrile and aldehydes by using highly efficient cesium carbonate in ethanol under microwave irradiation. Several advantages associated with this protocol such as high yields, easy accessibility, wide substrate scope and short reaction time. This methodology might prove as a better alternative to the existing literature methods.