Microwave Promoted and Improved Thermal Synthesis of Pyranocoumarins and Furocoumarins
Abstract
Propargyl ethers of 7-hydroxy-, 4-hydroxy-, and 4-methyl-7-hydroxycoumarins have been efficiently rearranged to pyranocoumarins and furocoumarins under microwave irradiation; improved thermal rearrangement of these ethers was also reported.