Protonated Mesoporous Aluminosilica Nanospheres Boosting Aza-Michael Cyclization and Diels-Alder Reaction
摘要
Mesoporous aluminosilica hollow nanospheres were prepared easily, which possess very strong acid site. The heterogeneous catalyst can be utilized in both intramolecular aza-Michael addition cyclization and intermolecular Diels-Alder reaction. The catalyst could be easily recovered and reused. Furthermore, the catalyst could be used in continuous flow chemistry for the uninterrupted synthesis of 2,3-dihydroquinolin-4(1H)-ones, which disclosed the potential application of the present solid catalyst in both academic and industrial syntheses. In addition, the catalyst could be recovered and reused at least 7 times without obvious loss of activity.