An efficient and green protocol for synthesis of novel [1,3]oxazino[5,6-c]quinolin-5-one derivatives using [Et3NH]HSO4 as a reusable catalyst

AbstractA simple, efficient, and eco-friendly procedure has been developed using acidic ionic liquid [Et3NH]HSO4 as catalyst for the synthesis of novel [1,3]oxazino[5,6-c]quinolin-5-one derivatives via one-pot three-component condensation reaction of 4-hydroxyquinolin-2(1H)-one, amine and formaldehyde in aqueous ethanol at room temperature. Mild and environmentally benign reaction conditions, short reaction time, good to excellent yields, nontoxic, cheap and easily available catalyst, reusability of catalyst and reaction media, and easy work-up are the key features of this method.