A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one‐pot, four‐component unsymmetrical Hantzsch condensation of dimedone, aldehydes, ethyl acetoacetate...A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one‐pot, four‐component unsymmetrical Hantzsch condensation of dimedone, aldehydes, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate [TBA]2[W6O19] under solvent‐free conditions has been developed. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and considerable catalytic activity was still achieved after the fifth run.展开更多
Cerium(IV) sulfate tetrahydrate, Ce(SO4)2·4H2O, is a novel inorganic solid acidic catalyst that efficiently catalyzes the synthesis of 2,3-dihydroquinazolin-4(1H)-ones via the one-pot three- component reaction of...Cerium(IV) sulfate tetrahydrate, Ce(SO4)2·4H2O, is a novel inorganic solid acidic catalyst that efficiently catalyzes the synthesis of 2,3-dihydroquinazolin-4(1H)-ones via the one-pot three- component reaction of isatoic anhydride, aromatic aldehydes, and a nitrogen source(ammonium acetate, ammonium carbonate, ammonium chloride, or methylamine) under solvent-free conditions. The desired products are obtained in short reaction time with high yields. The catalyst is inexpensive and readily available and can be recovered conveniently and reused such that considerable catalytic activity can still be achieved after the fifth run. Easy work-up and avoiding the use of harmful organic solvents are other advantages of this simple procedure.展开更多
基金supported by Islamic Azad University, Mashhad Branch, Iran
文摘A novel, efficient, and environmentally friendly method for the synthesis of polyhydroquinoline derivatives by a one‐pot, four‐component unsymmetrical Hantzsch condensation of dimedone, aldehydes, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of tetrabutylammonium hexatungstate [TBA]2[W6O19] under solvent‐free conditions has been developed. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and considerable catalytic activity was still achieved after the fifth run.
基金supported by Islamic Azad University,Mashhad Branch as research project (92429/302/64)
文摘Cerium(IV) sulfate tetrahydrate, Ce(SO4)2·4H2O, is a novel inorganic solid acidic catalyst that efficiently catalyzes the synthesis of 2,3-dihydroquinazolin-4(1H)-ones via the one-pot three- component reaction of isatoic anhydride, aromatic aldehydes, and a nitrogen source(ammonium acetate, ammonium carbonate, ammonium chloride, or methylamine) under solvent-free conditions. The desired products are obtained in short reaction time with high yields. The catalyst is inexpensive and readily available and can be recovered conveniently and reused such that considerable catalytic activity can still be achieved after the fifth run. Easy work-up and avoiding the use of harmful organic solvents are other advantages of this simple procedure.