Silica Gel Catalyzed Synthesis of Quinoxaline 1,4-Dioxides under Solvent-Free Conditions Using Microwave Irradiation
摘要:
We report on the simple and quick synthesis of quinoxaline 1,4-dioxides in solvent-free conditions under microwave irradiation. Heating of various benzofuroxans and beta-ketoesters or 1,3-diketones adsorbed on silica gel in a microwave oven for two minutes affords diverse biologically attractive quinoxaline 1,4-dioxides in high to excellent yields. Silica gel functions not only as support using microwave but also as catalyst and dehydration reagent.