A Facile Synthesis of 2-Methyl-4-oxo-4,5-dihydrofuroquinolines

Article abstract of DOI:10.1055/s-1989-27178

A facile route to 2-methyl-4-oxo-4,5-dihydrofuro<3,2-c>quinolines 5a-d has been developed by base-catalyzed thermal rearrangement of 4-(2-propynyl)oxyquinolin-2(1H)-ones 4a-d in good yields.The propynylation of 4-hydroxyquinolin-2(1H)-ones 1a-d furnished 3,3-di(2-propynyl)-2,4-dioxo-1,2,3,4-tetrahydroquinolines 2a-d. 4-(2-propynyl)oxy-3-(2-propynyl)quinolin-2(1H)-ones 3a-d, and 4a-d.A mechanistic pathway for the formation of 5 from 4 via 6 and 7 has been described.