Facile One-Pot Synthesis of Flavanones Using Tetramethylguanidinum-Based Ionic Liquids as Catalysts

Abstract Several tetramethylguanidinum-based ionic liquids (TMGILs) were prepared, characterized and used as catalysts in one-pot synthesis of flavanones. The results indicated that TMGILs composed of phenolate anion was beneficial for one-pot synthesis of flavanones, and [TMG][4-MeO–PhO] induced the good yields of flavanones owing to the electron-donating effect of methoxy substituent on phenolate anion. Furthermore, [TMG][4-MeO–PhO] was found to be used repetitively at least five times without obvious decrease in activity and quantity. Graphical Abstract